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Resume Les prescriptions medicamenteuses inadaptees voire dangereuses, entrainent une perte de chance pour les patients ainsi que des surcouts directs et indirects pour la societe. De ce fait, le sujet a une dimension ethique. Ce travail repose sur des rapports anterieurs, l’un parlementaire, les autres administratifs ainsi que de l’Academie nationale de medecine. Les principaux objectifs de la formation des etudiants dans ce domaine sont d’apprendre a prescrire juste, a surmonter les difficultes reelles des prescriptions en cas de polypathologies de plus en plus frequentes, notamment chez les malades âges. Le temps consacre aux enseignements de la pharmacologie, de la therapeutique peut etre globalement considere comme satisfaisant. En revanche ces enseignements et surtout leur memorisation ne sont pas suffisamment controles en fin de deuxieme cycle des etudes medicales. De plus, certains logiciels d’aide a la prescription manquent de clarte, de concision et de precision ce qui les rend peu utilisables. Dans le bon usage des medicaments on ne saurait oublier le role des pharmaciens d’officine, des associations de patients et de la formation continue. Ce rapport est volontairement limite a trois propositions qui decoulent des constatations precedentes : (1) Dans les etudes medicales, instituer un examen specifique et autonome, integre aux epreuves de l’examen classant national (ou de son equivalent), portant sur la pharmacologie et la therapeutique ; (2) Assurer une actualisation des connaissances dans ces domaines par la formation professionnelle continue ; (3) Etablir un seul logiciel clair, concis et precis d’aide a la prescription, elabore par les Conseils nationaux professionnels et qui soit labelise.

RESUME Un conflit d’interet a ete defini comme une situation d’interference entre une mission de service public et l’interet prive d’une personne qui concourt a l’exercice de cette mission. Initialement, la reflexion sur le sujet a surtout ete orientee vers la securite sanitaire et l’independance de l’evaluation des risques et de leur gestion. La qualite d’expert est etroitement liee a l’experience, aboutissant a l’assimilation des qualifications de specialiste et d’expert. Il est alors presque ineluctable que l’expert medical ait eu ou ait un lien d’interet avec les firmes pharmaceutiques et les fabricants de dispositifs medicaux. Paradoxalement, alors que les exigences sur les liens d’interets des experts sont de plus en plus pregnantes, depuis quelques annees le populisme scientifique et la suspicion generalisee vis-a-vis de toute decision ont abouti a contester les expertises. Les conflits d’interet ont ete definis de facons de plus en plus pertinentes et precises qui ont entraine une grande complexite des procedures et l’elimination inutile de candidats utiles. La collegialite de l’expertise minimise les risques que l’expertise soit entachee, mais expose a des influences predominantes. L’independance de jugement et l’objectivite des experts peuvent et doivent etre controlables et controlees par l’expertise methodologique a partir de donnees factuelles et de leurs niveaux de preuve. De facon generale, c’est a l’organisme qui sollicite les experts de se garder des marges de manœuvre suffisantes pour determiner des regles de comportement qui leur paraissaient adaptees aux questions particulieres qui se posent. Le role d’expertise des Academies par l’independance de ses membres, leur pluridisciplinarite, leur declaration de liens d’interet pourraient aujourd’hui en faire des instances privilegiees d’expertise.

RESUME La falsification des medicaments, (les medicaments falsifies), constitue un fleau mondial dont le trafic ne cesse de croitre. Dans tous les pays, notamment dans ceux en developpement, un prejudice grave est cree a l’egard des malades qui ne peuvent beneficier d’un acces a des medicaments de qualite en vue d’un traitement efficace. Plus recemment, la vente de medicaments sur Internet represente un danger supplementaire mondial. Face aux carences des acteurs de tous niveaux, au premier rang politiques, les moyens de lutte sont dramatiquement limites. A l’initiative de l’Academie de medecine, le rapport redige en commun avec les Academies de Pharmacie et Veterinaire de France rappelle l'imperative necessite d’une lutte contre ce trafic particulierement rentable et ses trafiquants, nouvelle mafia, hors de controle. Les Academies insistent sur la necessite de denoncer le prejudice sanitaire porte aux populations les plus demunies et, par le biais d’Internet, a toutes les Nations. Elles soulignent l’urgence d’adopter des mesures coercitives severes de la part des decideurs politiques, des organisations internationales et regionales concernees par cette lutte, et une mobilisation des industriels, des importateurs et distributeurs et des professionnels de sante de toutes disciplines. Elles preconisent en outre une communication forte, repetee et suivie sur le risque engendre par les medicaments falsifies aupres du public, y compris par le canal d’Internet. Elles insistent, en outre, sur la necessite d un suivi regulier des progres realises ou des carences maintenues.

RESUME L’Academie nationale de medecine, depuis plus de dix ans, considere la chirurgie ambulatoire avec un grand interet. Les estimations des economies qu’elle permettrait varient de 0,5 milliard a 6 milliards. Cela s’explique par l’absence d’etudes fondees sur des comparaisons factuelles bien etablies. De plus, les estimations reposent, en partie, sur des comparaisons internationales qui sont biaisees par l’absence de definition claire et concrete de cette « chirurgie ». Les tarifications en France sont d’une remarquable complexite. Schematiquement, 1) les couts pour le malade, pris en charge par l’assurance maladie et par les assurances complementaires, sont bases sur la notion de prix de journee et sont en faveur de la chirurgie ambulatoire par rapport a la chirurgie conventionnelle ; 2) les couts pour les etablissements hospitaliers sont, pour l’essentiel, le ratio entre les allocations versees par l’assurance maladie qui reposent sur la tarification a l’activite (T2A) et ses depenses, principalement salariales ; 3) le cout pour l’assurance maladie est celui qu’elle fixe elle-meme pour chaque activite medicale (T2A) au sein de l’enveloppe globale de l’Objectif national des depenses de sante (ONDAM), mais qui n’est pas un credit budgetaire limitatif. L’Academie nationale de medecine, sans remettre en cause le benefice pour le patient de cette alternative a la chirurgie traditionnelle, insiste sur la necessite de realiser en France des etudes comparatives avec la chirurgie conventionnelle portant sur les couts reels, directs et derives en s’appuyant sur une comptabilite analytique. L’analyse porterait sur des actes et des groupes de malades similaires. Par ailleurs, les propositions qu’elle avait faites pour une reforme de l’assurance maladie gardent toute leur valeur.

RESUME L’Academie nationale de medecine et l’Academie nationale de pharmacie considerent que le foisonnement et la diffusion incontrolables dans les medias et sur Internet d’informations souvent contradictoires sur les medicaments, y compris les vaccins, aboutissent a une perte des reperes et parfois a une perte de confiance dans les messages des institutions officielles. Preoccupees par les effets deleteres pour la sante publique que sont susceptibles de provoquer certaines de ces informations, quand elles sont alarmantes, caricaturales, insuffisamment fondees ou meme erronees, elles emettent un certain nombre de recommandations destinees a permettre de faire davantage emerger, a titre de repere indiscute, dans ce contexte de confusion et de dissonance, une information objective, impartiale, scientifiquement fondee, facilement accessible et comprehensible pour le public. Ces recommandations s’adressent aux emetteurs d’informations les plus qualifies que sont d’abord les pouvoirs publics et les autorites et agences de sante dont les trop nombreux silences, mais aussi le manque de reactivite et la production de messages peu adaptes au grand public ne permettent pas une presence suffisamment forte et visible dans les debats et polemiques ; ensuite a l’Assurance maladie qui devrait davantage donner acces aux tres nombreuses donnees dont elle dispose et davantage les exploiter ; aux societes savantes qui doivent se garder de cautionner et de promouvoir des informations prometteuses mais non encore confirmees ; aux professionnels de sante qui restent les sources principales d’information du public et les meilleurs relais des informations emanant des autorites et dont la credibilite des messages repose non seulement sur l’actualisation de leurs connaissances mais aussi sur leur independance ; enfin aux associations de patients et aux patients qui, dans leur quete d’informations, doivent prioritairement recourir a leurs medecins et a leurs pharmaciens, en particulier ne jamais interrompre brutalement un traitement en cours ou modifier sa posologie sans leur en avoir prealablement parle et faire preuve de la plus grande prudence vis-a-vis de documents ou messages electroniques ou non dont l’origine et la qualite ne sont ni identifiees ni validees.

RESUME C’est le but que s’etait fixe le groupe de travail de l’Academie nationale de medecine compose de sept membres sous la direction de Rene Mornex pour essayer d’obtenir une medecine sobre qui dans une approche humaniste soigne mieux au moindre cout. Vingt-six auditions de diverses personnalites essentiellement medicales (soit internes soit externes a l’Academie), mais aussi administratives, ministerielles, ou institutionnelles sont venues nourrir, critiquer, ou renforcer nos propres reflexions, qui s’appuyaient aussi sur les 7 rapports ou communiques precedemment produits et diffuses par notre Academie. La premiere partie a consiste a faire un etat des lieux qui a permis de constater que si la connaissance des recommandations des bonnes pratiques edictees par l’HAS etait bonne, leur application ne l’etaient pas, raisons de nombreuses derives, pour les bilans de sante, pour les depistages de masse (exemple PSA), pour les examens biologiques trop souvent reclames « en bloc », ou d’imagerie legere (comme l’echographie) ou lourde (Scanner, IRM) trop souvent utilisee en premiere ligne devant une pauvrete voire une absence de l’examen clinique. Ces derives pouvaient s’etendre aux prescriptions medicamenteuses, voire aux actes chirurgicaux a la mode souvent permis par l’acces direct au chirurgien sans intermediaire medical ou paramedical. L’etude des responsabilites retrouve la modification des conditions d’exercice avec la presence de plus en plus frequente de l’ecran d’ordinateur s’interposant entre praticien et patient qui ne favorise ni l’interrogatoire ni l’examen clinique. Mais aussi l’activite medicale est sensibilisee de plus en plus par le principe de precaution et le risque de judiciarisation, facteurs declenchant les prescriptions larges « pour se couvrir », temoin en realite d’une attitude defensive deletere, illusoire et inefficace, comme l’ont montre nos auditions assurancielles ou juridiques. Bien sur enfin l’environnement societal par la voix envahissante des medias souvent irresponsables vis-a-vis du patient mais favorisantes pour le consumerisme medical et l’exigence de rapidite exigee par le malade aussi bien pour le diagnostic ou la therapeutique. Les pistes d’ameliorations devront 1 : d’abord se tourner vers l’enseignement de la medecine avec en particulier une reforme serieuse et complete du 2e cycle de la formation initiale du medecin. La segmentation extreme cree par la succession des « certificats de specialites » n’aboutit qu’a une succession d’assimilationregurgitation qui gene non seulement la prise en compte globale du malade mais aussi la memorisation de la semiologie de base et son integration dans l’ensemble du malade ne favorisant pas du tout les choix strategiques des examens complementaires biologiques ou d’imagerie, pas plus que les orientations therapeutiques. L’enseignement clinique doit se faire sur une duree plus longue que les 3 mois actuels avec des enseignements transversaux y compris la pharmaco therapeutique quasiment inexistante. Surtout une evaluation a intervalles reguliers devrait permettre ou non de se presenter au fameux Examen Classant National qui actuellement est le seul but des etudiants en Medecine qu’ils preparent en « bachotant », qui est rempli de lacunes (pas de points negatifs, pas de question sur la strategie diagnostique, pas plus que de questions sur avantages/inconvenients de telle ou telle therapeutique, etc.) D’ou une refonte complete de cet examen classant s’impose. La formation medicale continue, avancee considerable, doit etre revue pour la rendre encore plus efficace en la sortant si possible de plus en plus independante ou controlee vis-a-vis des marketings commerciaux. 2 : Le developpement des recommandations de bonne pratique clinique, souvent coordonnee par l’HAS, est une bonne chose et sont consultes mais souvent avec des textes trop longs de sorte qu’ils sont peu appliques. Ils ne devraient pas depasser 2 pages et donner surtout des indications de cadrage de la pathologie rapportee. 3 : L‘organisation des soins doit tourner de plus en plus vers le parcours de soins et le regroupement des competences aussi bien publiques que privees, avec le developpement des reseaux regionaux, bases sur l’auto adhesion, la reconnaissance par le praticien lui-meme de ses limites de competence medicale et de plateaux techniques. Ceci realise vraiment la strategie pertinente pour chaque pathologie et chaque patient. Les Reunions de Concertation Pluridisciplinaires (RCP) obligatoires pour les pathologies du Cancer en sont aussi un bon exemple si elles gardent un caractere impartial et humain en y incluant fortement le medecin traitant. L’imagerie medicale meriterait une telle reorganisation ou le choix de l’imagerie pertinente reviendrait a l’imageur lui-meme. De meme a l’exemple de plusieurs pays d’Europe, les centres charges des pathologies lourdes devraient etre en nombre limite repartis sur tout le territoire national en accord inter-regional avec les diverses ARS. Les exemples des Instituts de cancerologie dans certains pays ou des « traumas centers » dans d’autres meriteraient d’etre examines. Le mode de financement « dit a l’activite » (T2A) facteur de glissements nefastes et dans les indications et dans les actes, doit etre revu pour valoriser la pertinence et la qualite. Par ailleurs la remuneration des activites medicales devraient valoriser l’acte intellectuel par rapport a l’acte technique ce qui est l’inverse de l’etat actuel, avec les 3 leviers dont pourrait disposer la CNAM : Nomenclature, Entente prealable, Controles avec pour ces derniers l’utilisation d’interlocuteurs adaptes, plus âges, plus experimentes, plus specialises. La pertinence des strategies medicales est une caracteristique essentielle du bon exercice de la medecine. Sous la responsabilite totale des medecins, etat d’esprit, synonyme de qualite et de securite, s’enseigne par compagnonnage, evolue constamment, n’entrave pas les innovations, tout en realisant une efficience economique en ameliorant la qualite des soins respectant les droits fondamentaux du patient.

RESUME Les recents retraits de medicament pour des raisons de securite rappellent sans cesse l’absolue necessite d’une pharmacovigilance efficace. Ce rapport rappelle la place importante de la pharmacovigilance dans l’evaluation des medicaments et la surveillance de leurs effets. Apres avoir discute les grandes methodes utilisees en pharmacovigilance, il formule un certain nombre de propositions pour renforcer l’efficacite de la pharmacovigilance, donc la securite des prescriptions et des patients. Ces recommandations concernent 1) l’enseignement, la formation et l’information des professionnels de sante en pharmacovigilance, 2) une meilleure implication et prise en compte de la pharmacovigilance dans la pratique medicale et 3) le developpement d’une recherche specifique sur les effets indesirables medicamenteux.

RESUME Les effets deleteres potentiels des medicaments administres a la mere sur l’enfant in utero se referent habituellement a une eventuelle teratogenicite. Les consequences possibles des medicaments recus passivement en fin de grossesse sur l’adaptation neonatale ne sont pas suffisamment connues des prescripteurs. Independamment des medicaments de l’analgesie obstetricale, la problematique concernerait plus de 15 % des nouveau-nes. Ce rapport a pour objet de rappeler les risques encourus du fait de « l’heritage medicamenteux » afin d’ameliorer la securite des naissances dans des conditions de prescriptions par ailleurs legitimes. Les auteurs rappellent les modifications des parametres pharmacologiques en cours de grossesse et la chronologie de l’exposition embryonnaire et fœtale, ainsi que les particularites du passage placentaire des medicaments. En se referant aux princi- paux phenomenes de l’adaptation physiologique neonatale, les alterations possi- bles des grandes fonctions sont enoncees, en particulier, pour le systeme nerveux, la respiration, la circulation..... Les effets fœtaux et neonataux des grandes classes pharmacologiques sont resumes en distinguant les medicaments formellement contre-indiques en fin de grossesse et ceux qui, bien qu’utilisables, necessitent des precautions et des protocoles de surveillance neonatale appropries. Dans les recommandations de l’Academie nationale de medecine, il est insiste sur la necessite d’une information specifique sur les risques neonataux des medicaments recus in utero tant aupres des professionnels de la sante que des futures meres. Cette information incombe aux enseignants des diverses disciplines, aux laboratoires fabricants et aux autorites d’enregistrement des produits de sante. Elle doit par ailleurs etre accessible a tous, en particulier, grâce a la consultation du Centre de reference sur les agents teratogenes (CRAT).

RESUME Les medicaments generiques permettent de concurrencer les medicaments qui ont perdu leur exclusivite, leur brevet etant tombe dans le domaine public. N’ayant pas a supporter le poids enorme de la recherche et du developpement, leur prix de vente inferieur a celui du medicament princeps, permet, en principe, de diminuer les depenses de sante et de faciliter l’acces aux soins de populations economiquement defavorisees. Des leur apparition, ils ont ete a l’origine de nombreuses controverses portant sur leur efficacite et leur tolerance. Leur role dans les difficultes economiques que les industriels du medicament doivent affronter actuellement en France, a ete evoque.

RESUME L’Academie nationale de medecine souhaite : que soit developpee la notification des effets indesirables par l’ensemble des professionnels de sante mais aussi des patients ; que soient mises en œuvre systematiquement des etudes cliniques post-AMM et des etudes de pharmaco-epidemiologie, dont les resultats soient rendus publics sur un site Internet dedie ; que soient ameliorees les informations relatives aux produits, notamment celles qui figurent sur les notices des conditionnements des medicaments ; que ces mesures s’inscrivent dans une veritable eurovigilance du medicament ; que la notification des effets indesirables soit facilitee par des declarations simplifiees, (electroniques) ; que soient favorisees les relations entre les prescripteurs, les dispensateurs et les centres regionaux de pharmacovigilance ; que toute notification fasse l’objet d’un retour personnalise au notificateur. Que la formation initiale en pharmaco-therapeutique soit renforcee, sous la responsabilite conjointe des enseignants de pharmacologie et de therapeutique : apprentissage de la lecture critique d’articles, du bon usage du medicament, de la decision therapeutique concrete et personnalisee, de la notification des effets indesirables ; que soit creee une validation specifique destinee a verifier l’acquisition d’une authentique competence en pharmaco-therapeutique, avec place accrue dans le cadre de l’examen classant national (ECN) de fin du second cycle. Que la pharmacovigilance fasse l’objet d’un module particulier dans le cadre du developpement professionnel continu (DPC), avec seances communes aux medecins et aux pharmaciens. Que soit renforcee la demarche d’imputabilite incluant deux etapes : — celle de la suspicion basee sur l’identification du symptome d’alerte ; — celle de confirmation par des etudes epidemiologiques, avec methodologies appropriees aux polytherapies, permettant l’identification de cas nouveaux ou severes, notamment inattendus, rares et/ou tardifs ; que les relations scientifiques entre les instances d’evaluation et le titulaire de l’AMM, ainsi que son responsable de pharmacovigilance, soient plus exigeantes et plus efficaces ; qu’il soit fait appel aux societes savantes et aux organismes de recherche en cas de besoin ; qu’une formation universitaire specifique continue d’etre exigee pour diriger un Centre. Que les etudes de type pharmaco-epidemiologique soient developpees et valorisees ; qu’elles fassent systematiquement et sans delai l’objet de publications scientifiques, y compris les etudes dont les resultats sont negatifs ; qu’elles soient davantage prises en compte et que leurs resultats soient rendus publics avec declaration publique d’interets, beneficient de methodologies appropriees, beneficient reglementairement de toutes les donnees existantes, publiques et privees, francaises et internationales utilisant notamment les donnees des reseaux europeens. Que soient mises a la disposition des patients les informations pratiques adaptees a la notification des effets indesirables (ou, comment, aupres de qui notifier... ?) ; que l’on s’appuie sur les associations de malades comme source et comme relais d’informations ; que ce type de demarche fasse partie integrante du cursus scolaire, dans le cadre de l’education des citoyens et des patients sur le medicament ; que la premiere annee des etudes universitaires des professionnels de sante (L1) soit utilisee pour permette de transmettre ces messages a une large partie de la population etudiante.

RESUME L’ischemie reperfusion (IR) est un episode deletere, incontournable de la transplantation d’organes. La conservation hypothermique permet de la limiter en reduisant l’activite metabolique des organes conserves. Cependant, la conservation en hypothermie induit un syndrome physiopathologique complexe responsable de plusieurs processus lesionnels. Les consequences sont importantes sur le devenir a court terme en retardant le fonctionnement des organes greffes et a long terme en participant a l’apparition de lesions chroniques.

RESUME Ces propositions decoulent de l’etat des lieux, presente a l’Academie nationale de medecine en juin 2010. Leur objectif est d’ameliorer l’efficience de l’assurance maladie en France tout en maintenant ses grands principes de solidarite, d’humanisme, de liberte et de responsabilite. Pour la prise en charge des affections de longue duree (pres de neuf millions de personnes et de 60 % des depenses de remboursement) : — des definitions plus precises doivent etre donnees ; — les durees d’admission doivent etre mieux adaptees aux donnees actuelles de la medecine ; — il convient que les protocoles medicaux de surveillance et de traitement soient plus precis. Dans les etablissements hospitaliers il faut — diminuer les effectifs de personnel administratif et redeployer dans les services de soins le personnel soignant, affecte actuellement sur des postes administratifs ; — recentrer l’activite des medecins sur les soins en les soulageant des tâches administratives qui les accablent ; — controler le bien-fonde des prescriptions medicales et la pertinence des actes. Le service medical des caisses : meriterait d’etre reorganise dans un service unique pour tous les regimes, independant des services administratifs ; — son statut (recrutement, formation, promotions) doit etre modifie ; — le recrutement d’hospitalo-universitaires consultants et de praticiens hospitaliers retraites volontaires, permettrait de mieux assumer une fonction de conseil en matiere d’hospitalisation ; — par ailleurs, une augmentation des effectifs du service medical est indispensable. En matiere de medicaments, les mesures doivent prendre en compte, a cote de l’aspect purement medical, la recherche, l’economie et l’industrie ; — les medicaments dont l’utilite n’est plus justifiee aujourd’hui ne doivent pas etre rembourses ; — en revanche, le deremboursement total des medicaments a faible service medical rendu, risque d’aboutir a une substitution par de nouveaux medicaments plus couteux ; les consequences medicales des decisions concernant le prix de remboursement des medicaments devraient etre mieux prises en compte ; — par dessus tout, il est indispensable, de parvenir a un bon usage des medicaments ; pour les medecins par la formation initiale en pharmacologie et en therapeutique, puis par la formation continue ; pour le public par une education a la sante correcte et objective. D’autres propositions generales sont : — d’inciter a des comportements responsables par le retour a un ticket moderateur d’ordre public qui devrait etre module ; — un controle des moyens humains et materiels affectes a l’offre de soins beaucoup plus rigoureux ; — en sante publique , un renforcement de la lutte contre le tabagisme, l’alcoolisme et, plus generalement, contre toutes les drogues ainsi que contre l’obesite.

An audit of the French national health insurance system would be justified by economic considerations alone, but this would risk overlooking the notions of solidarity and freedom to which the French are rightly attached. European comparisons suggest, however, that our system could be made more efficient without undermining public health. The national health insurance system allows each member of the population to receive high-quality medical care. Practitioners have near-total freedom of prescription and practice. Medical care contributes to the ongoing increase in life expectancy, which is currently 73 years and second only to Japan. Healthcare is also a source of a million jobs. Macro-economic spending controls have failed, owing to medical progress and population aging, and also to medical consumerism favored by an unprecedented range of examinations and treatments, the increasing reimbursement of medical care, and the extension of direct payment by the insurer. Many ineffective measures have been implemented, such as tarification according to activity, and hospital certification. Health spending is also increased unnecessarily by bureaucratisation of healthcare spending and the transfer of professionals to posts for which they are not qualified. Some controversial medical prescriptions are not adequately controlled by the health service. Many reforms are based on over-optimistic economic predictions that fail to take related overheads into account. Lobbying by special interests groups undermines reform and the public interest. Too many independent administrative bodies have been created, and many are less efficient than the public structures they replaced. In sum, the French national health insurance system has become less and less efficient over the years.

RESUME L’insuffisance de formation des etudiants en medecine en Pharmacologie et en Therapeutique a ete denoncee de facon repetee par l’Academie nationale de medecine. En particulier, Paul Lechat a propose, des 1993, que la therapeutique medicamenteuse devienne un objectif institutionnel des etudes, que cet objectif soit atteint et verifie par des validations specifiques, que les futurs medecins soient capables de faire une lecture critique des publications de therapeutique, enfin que le poids de la therapeutique aux examens soit augmente. Ces recommandations n’ont ete prises en compte que partiellement. Les insuffisances de ces enseignements ont trois causes principales : des heures de cours trop limitees, l’absence de validation specifique, un defaut de coordination entre les enseignements. Il est propose de les coordonner de facon tres etroite, d’identifier leurs objectifs, de les valider de facon autonome et d’introduire un pourcentage consequent de questions de pharmaco-therapeutique dans l’examen classant national. Il apparait aussi qu’une mise a jour des connaissances est indispensable dans le cadre de la formation medicale continue. L’integration necessaire des structures francaises d’enseignement dans le cadre de la Communaute Europeenne en trois etapes : licence, master et doctorat, offre la possibilite de mieux situer les enseignements de pharmacologie et de therapeutique dans le cursus des etudes medicales. Le contenu et la place des differentes interventions sont proposes dans ce nouveau cadre. L’Academie nationale de medecine recommande leur application.

RESUME Les principales classes pharmacologiques de l’automedication: analgesiques, antitussifs, antihistaminiques, regulateurs des fonctions digestives n’utilisent que des medicaments en principe bien toleres dans leurs conditions normales d’emploi. Les effets indesirables que l’on observe sont dus a des mesusages: mauvaise indication ou surdosage, associations intempestives avec des medicaments prescrits ou encore parce qu’un mauvais choix masque une maladie grave. Ils sont en grande partie evitables. La mise en evidence de ces effets indesirables est pratiquement acquise lorsqu’ils sont graves car ils entrainent une hospitalisation. En revanche, les effets indesirables moins graves sont plus delicats a collecter. Ils peuvent l’etre par les professionnels de sante au contact de l’utilisateur: son medecin traitant, le pharmacien qui a delivre le medicament, la societe pharmaceutique qui l’a fourni. Ils peuvent aussimener des activites de prevention utilisant les moyens informatiques actuels et des structures d’ecoute et de veille.

RESUME L'HSA (human serum albumin) et l'AGP (alpha glycoprotein) sont les seules proteines plasmatiques capables de lier les medicaments par des sites specifiques avec une forte affinite. Elles limitent alors leur distribution et parfois leur elimination. Ces liaisons sont dites restrictives par opposition aux liaisons de faible capacite, dites permissives sans pouvoir retentionnel significatif. Toute modification de la capacite de fixation d'une liaison restrictive entraine des variations des autres parametres pharmacocinetiques et en consequence des effets produits.

Ischemia-reperfusion injury (IRI) represents an allo-independent risk factor which favors chronic allograft nephropathy (CAN). Here we analyzed the influence of preservation solutions on the function of autotransplanted pig kidneys over 1-16 weeks after surgery. Kidneys were cold-flushed and cold-stored for 24 or 48 h either in University of Wisconsin (UW), modified-UW Hôpital Edouard Herriot, polyethylene glycol 20 kDa (PEG)-supplemented preservation solutions with low K+ (ECPEG) or high K+ (ICPEG) content. Animals autotransplanted with kidneys cold-stored for 24 h in ECPEG exhibited the greatest levels of creatinine clearance (Ccr: 161 +/- 12 mL/min, n=10) and the lowest levels of proteinuria (0.5 +/- 0.03 mg/mL) 16 weeks after surgery as compared with pigs autotransplanted with kidneys cold-stored in the other solutions tested (Ccr ranging from 80 and 140 mL/min). Similar differences, but with lower Ccr levels, were achieved after a prolonged period of cold-storage(48 h). ECPEG better preserved the kidneys from monocytes/macrophages and CD4+ T cells infiltrations, VCAM-1 and MHC class II overexpressions and occurrence of renal interstitial fibrosis (2%) as compared with the other preservation solutions (5%-20%). Adding the anti-ischemic drug trimetazidine (TMZ) to the preservation solutions, particularly ECPEG, further improved the quality of the week-16 post-transplanted kidneys (Ccr: 182 +/- 12 mL/min, n=10). These findings demonstrated that adding PEG to extracellular-like (with low K+ content) preservation solutions in combination with TMZ significantly improved the long-term outcome of kidney grafts in this model of autotransplanted pig kidney.

Ischemia-reperfusion injury (IRI) is associated with an increased risk of acute rejection, delayed graft function, or chronic graft dysfunction. Mitochondria plays a central role in this process. Using an autotransplant pig kidney model, changes in renal function and morphology were determined after different periods of cold ischemia in kidneys preserved in the University of Wisconsin solution (UW), high-Na(+) version of UW (HEH) or Celsior (CEL) a newly developed high-Na(+) solution, with or without trimetazidine (TMZ). Kidney function was better preserved in HEH after 24 hr and particularly 48- and 72-hr cold storage than in CEL and UW. TMZ improved the preservation quality when added to the different solutions tested, particularly after 48- and 72-hr cold storage. Interstitial fibrosis and tubular atrophy were reduced in HEH with TMZ. CD4(+) T-cell infiltration was also modulated by the preservation conditions. Peripheral-type benzodiazepine receptor (PBR) positive cells infiltration was also modulated by preservation conditions. TMZ was efficient to reduce IRI when added in the various preservation solutions. These results suggest that protection of the mitochondrial function should be a major target to limit IRI. In addition, this study outlines the role of CD4(+) T cells and PBR expression in inflammatory responses after IRI.

Rat brain mitochondria were successively submitted to anoxia and reoxygenation. The main mitochondrial functions were assessed at different reoxygenation times. Although the respiratory control ratio decreased, the activity for each one of the enzymes participating in the respiratory chain was not affected. However, during reoxygenation, mitochondrial membrane lipoperoxidation quickly increased and was proportional to the decrease seen in membrane fluidity. Under the same conditions, cytochrome c and cardiolipin were released from mitochondria and their rate of release increased with reoxygenation time. The release of cytochrome c and cardiolipin was followed by the collapse of the membrane potential and it was not inhibited by cyclosporin A. Addition of the antioxidant alpha-tocopherol abolished all these reoxygenation-induced changes. These data indicate that, in this model, reoxygenation promotes the uncoupling of respiratory chain, and cytochrome c and cardiolipin releases. These events are not related to the membrane potential collapse but to an oxidative stress.

Mitochondrial Ca2+ accumulation can induce a sudden increase in the permeability of the inner membrane. This phenomenon is due to the generation of a large nonselective ion channel, termed the permeability transition pore (PTP), which contributes to cellular injury during ischemia and reperfusion. Inhibition of PTP generation constitutes a relevant pharmacological target to protect a cell from death. In this study, we examined the effect of S-15176 ((N-[(3,5-di-tertiobutyl-4-hydroxy-1-thiophenyl)]-3-propyl-N′-(2,3,4-trimethoxybenzyl)piperazine), a novel anti-ischemic agent, on PTP in rat liver mitochondria. S-15176 prevented PTP opening generated by various triggering agents, as attested by the concentration-dependent inhibition of mitochondrial swelling, of mitochondrial membrane potential dissipation and of NADPH oxidation. These effects were associated with an increase in the Ca2+ loading capacity of mitochondria. S-15176 was a strong inhibitor of lipid peroxidation, but experiments with another trimetazidine derivative devoid of antioxidant activity indicated that this activity was not essential to the inhibitory effect. Binding studies demonstrated that [3H]S-15176 bound to mitochondrial binding sites, especially those localized in the inner membrane. These sites were shared by several well-known inhibitors of PTP opening. These results demonstrate that the mechanism by which S-15176 protects mitochondria against the deleterious effects of ischemia–reperfusion involves inhibition of PTP opening and provide evidence that the drug operates through low structural specificity binding sites located in the inner mitochondrial membrane.

Epidemiological studies have reported that cigarette smoking may protect from neurodegenerative diseases such as Parkinson's disease. These protective effects are thought to be mediated by nicotine. Recent data showed that nicotine significantly decreases respiratory control ratio (RCR) and superoxide anion generation of brain mitochondria. Thus, we investigated nicotine effects on rat brain in two experimental models: first, an in vitro anoxia/reoxygenation experiment and secondly, an in vivo rotenone-induced Parkinson-like syndrome. Anoxia/reoxygenation impaired mitochondrial respiration by 43.68% whereas in the presence of nicotine, it was less impaired, by 31.1% at 10(-7) M. In rats chronically administered rotenone (3 mg/kg/day), we observed profound mitochondrial damage: the RCR decreased by 50.36% and the superoxide anion generation and the membrane anisotropy increased by 56.03 and 13.43%, respectively. All of these indications of mitochondrial damage were limited by chronic administration of nicotine. Nicotine developed mitochondrial effects in vivo and in vitro at very low concentration. All these results were in accordance with epidemiological studies, which report a protective effect of nicotine in neurodegenerative diseases. Thus, we propose that one effect of nicotine is to preserve mitochondrial functions of the rat central nervous system.

Resveratrol protection on the main functions of purified rat brain mitochondria submitted to anoxia-reoxygenation was investigated. Resveratrol (

A number of heterogeneous drugs previously shown to bind to trimetazidine (TMZ) binding sites on mitochondria and to inhibit mitochondrial swelling (Morin et al., Br J Pharmacol 1998;123:1385-94) were investigated here for their physicochemical properties. The molecular parameters measured were the partition coefficients of the neutral and monocationic forms in the n-octanol/water and dichloroethane/water systems, their distribution coefficients at pH 7.4 in these two solvent systems, as well as their distribution coefficients at pH 7.4 in a phosphatidylcholine (PhC) liposomes/water system (log D(lip)(7.4)). Most of these properties were not correlated with affinity to mitochondria or inhibition of mitochondrial swelling. In contrast, log D(lip)(7.4) showed a modest correlation with binding to the low-affinity site (r(2)=0.52) and a better correlation with anti-swelling activity (r(2)=0.69), itself well correlated with binding to the low-affinity sites (r(2)=0.83). Thus, these sites have recognition properties much like those of membranes, as they depend on lipophilicity-hydrophobicity (core binding) and ionic bonds (surface interactions).

RESUME Nous avons recherche sur un modele experimental d’anoxie-reoxygenation applique a des suspensions de mitochondries isolees d’encephale de Rat, les effets du resveratrol ajoute a la preparation ou injecte au prealable a des rats dont on a ensuite extrait les mitochondries. Sur ce modele, on observe que le resveratrol s’oppose aux effets decouplants induits par l’anoxie et la reoxygenation. Il inhibe ainsi totalement la liberation de cytochrome c intermembranaire, stade initial de l’apoptose mitochondriale, et s’oppose a la formation d’ATP qui l’effectue. Ces effets sont concentration-dependants et s’observent a des concentrations tres basses. On en conclut que le resveratrol limite ou supprime les effets deleteres mitochondriaux provoques par une anoxie suivie de reoxygenation.

We investigated the antiischemic properties of a new compound, S-15176, in an experimental model of rat liver subjected to 120-min normothermic ischemia followed by 30-min reperfusion. Rats were divided into groups, pretreated with different doses of S-15176 (1.25, 2.5, 5 and 10 mg/kg/day by intramuscular injection) or solvent alone, and subjected to the ischemia--reperfusion process. Another group served as the sham-operated controls. Ischemia--reperfusion induced huge alterations of hepatocyte functions, namely, a decrease in ATP content and bile flow, and membrane leakage of alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT). These effects were associated with alterations in mitochondrial functions characterized by (1) a decrease in ATP synthesis, (2) a decrease in NAD(P)H levels and mitochondrial membrane potential, and (3) an increase in mitochondrial swelling reflecting the generation of permeability transition. Pretreatment of rats with S-15176 alleviated these deleterious ischemia--reperfusion effects at both the cellular and mitochondrial levels in a dose-dependent manner. The protection of mitochondrial functions was almost complete at a dosage of 10 mg/kg/day. In addition, in vitro, S-15176 totally abolished the swelling of isolated mitochondria induced by a calcium overload with an IC(50) value of 10 microM. These data demonstrate that S-15176 protects mitochondria against the deleterious effects of ischemia-reperfusion and suggest that this protective effect could be related to the inhibition of the mitochondrial permeability transition.

The cessation of blood flow followed by a reperfusion period results in severe damages to cell structures. This induces a complex cascade of events involving, more particularly, a loss of energy, an alteration of ionic homeostasis promoting H + and Ca 2+ build up and the generation of free radicals. In this context, mitochondria are highly vulnerable and play a predominant role in the cell signaling leading from life to death. This is why, recently, efforts to find an effective therapy for ischemia–reperfusion injury have focused on mitochondria. This review summarizes the pharmacological strategies which are currently developed and the potential mitochondrial targets which could be involved in the protection of cells.

Oxidative damage to proteins results in biological dysfunctions such as perturbed activity in enzymes, transport proteins, and receptors. Here, we investigated structural damage to proteins induced by free radicals. Structural alterations to lysozyme, human serum albumin (HSA) and beta-lactoglobulin A were monitored by capillary zone electrophoresis. Four well-known antioxidants (quercetin, melatonin, Trolox, and chlorogenic acid) were examined for their ability to inhibit protein damage and to bind to these proteins. Melatonin and chlorogenic acid, which did not bind to any of the three proteins under study, showed scavenging and protective activities well correlated with the amount of free radicals generated. Trolox, which bound only to HSA, was a better protector of HSA than of the two other proteins, indicating that its antioxidant capacity is increased by a shielding effect. Finally, quercetin was a good antioxidant in protecting lysozyme and beta-lactoglobulin A, but its binding to HSA resulted in a pro-oxidant effect that accelerated HSA fragmentation. These results demonstrate that binding of an antioxidant to a protein may potentiate protection or damage depending on the properties of the antioxidant.

International audience; STUDY OBJECTIVE: The aim of the study was to assess diagnosis value of tumor markers for differential diagnosis between mesothelioma and other pleural tumors. DESIGN AND METHODS: Prospective study of 85 patients attending our hospital with malignant pleural effusion. The diagnostic approach involved routine pleurocentesis followed by pleural needle. When precise diagnosis was not achieved, thoracoscopy with pleural biopsies was performed. Carcinoembryonic antigen (CEA), hyaluronic acid, tissue polypeptide antigen and cyfra 21 to 1 were measured in serum and pleural fluid. RESULTS: By using receiver operating characteristics curves and area under curves, the best diagnostic characteristics were obtained with pleural and serum CEA concentrations. The area under the curve was larger for pleural ACE than for serum ACE. The sensitivity and specificity of a pleural CEA level exceeding 3 ng/mL for ruling out the diagnosis of mesothelioma were 100% and 77%, respectively. CONCLUSION: A CEA level above 3 ng/mL in pleural fluid eliminated the diagnosis of mesothelioma, whereas the other markers were not sufficiently discriminant. However, despite a negative predictive value of 100% at a cutoff of 3 ng/mL, CEA assay in pleural fluid only avoids a small number of diagnostic thoracoscopies.

The aim of this study was to investigate beta(1)- and beta(2)-adrenoceptor signalling systems in the rat brain studying the synergistic effects between beta-adrenoceptor agonists and forskolin- induced activation of adenylyl cyclase. Experiments were performed in slices from cerebral cortex and cerebellum because they contain mainly beta(1)- and almost exclusively beta(2)- adrenoceptors, respectively. Five beta-adrenergic agonists were used, clenbuterol, flerobuterol, isoproterenol, salbutamol, and tulobuterol. All agonists stimulated cyclic AMP accumulation in the cerebral cortex but flerobuterol was inactive in the cerebellum. Forskolin amplified the generation of cyclic AMP. Forskolin potentiation was observed in glial cells but not in neurons and was not dependent on the number of beta-adrenoceptors. In return the amplitude of the potentiation was highly dependent on the intrinsic activity of the agonist in the cerebral cortex whereas it was constant whatever the agonist tested in the cerebellum. To analyse this difference we developed a modelling approach using a concentration-response study. Isoproterenol and forskolin stimulations of cyclic AMP production were studied either alone or in combination with increasing concentrations of forskolin and isoproterenol, respectively. In the cerebral cortex isoproterenol and forskolin were both able to potentiate the cyclic AMP accumulation induced by the other compound, whereas, in the cerebellum, isoproterenol was unable to increase the stimulation induced by forskolin. The results support the hypothesis that beta(1)- and beta(2)-adrenoceptors display distinct mechanisms of action in the signalling system by which they stimulate the accumulation of cyclic AMP.

Ischaemia-reperfusion induces structural and functional damage to hepatocytes. The purpose of this study was to evaluate the protective effect of trimetazidine, an anti- ischaemic drug, in a rat liver model of ischaemia-reperfusion. Male Wistar rats were divided into groups pretreated with different doses of trimetazidine (1, 5, 10 or 20 mg kg-1 day-1) or saline for 7 days. Liver ischaemia was induced for 120 min and blood reflow was subsequently restored for 30, 60, 90 or 120 min. The activities of alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT) as well as the bile flow and the liver ATP content were determined. Ischaemia-reperfusion induced major alterations of hepatic functions involving increases of ASAT and ALAT activities, a drop of ATP content and a sharp decrease in bile flow. Trimetazidine pretreatment reduced the liver injury. Indeed, it lowered the increase in ALAT and ASAT activities observed immediately after reperfusion and maintained higher concentrations of hepatic ATP. Simultaneously, bile flow was increased. These effects were dose-dependent and 5 mg kg-1 day-1 seemed to be the lowest effective dose. In this experimental model trimetazidine pretreatment reduced the liver damage induced by ischaemia-reperfusion. Our data suggest that trimetazidine may be a useful drug in liver surgery to prevent ischaemia-reperfusion injury.

Human alpha1-acid glycoprotein (AAG) exists as an heterogeneous population of two or three genetic variants (ORM1 F1 and/or S and ORM2 A) in the plasma of most individuals. The ORM1 and ORM2 variants have a separate genetic origin. AAG belongs to the acute-phase proteins, which, under conditions of inflammation, increase several-fold in concentration. Additionally, there is evidence to suggest that it is not only the concentration but also the distribution of the two gene products of AAG (ORM1 and ORM2) that alter in such conditions. Variations of the relative concentrations of the AAG variants in certain diseases, such as cancer, can only be shown by reference to data collected in healthy people. In this study, we have investigated a group of 74 healthy subjects (42 men and 32 women) for AAG concentrations, AAG phenotypes and relative proportions of genetic variants in plasma. The specific assay of AAG was carried out by an immunonephelometric method and the phenotyping was performed, after desialylation of AAG, by analytical isoelectric focusing. Detection of the AAG variants was made by immunoblotting and their relative proportions were determined by laser densitometry analysis. The AAG plasma concentrations in the healthy group ranged between 0.28 and 0.92 g/l (mean value 0.50+/-0.14 g/l). The relative proportions of the variants derived from the two genes of AAG were variable, depending on the individual, but the amount of ORM1 variants almost always exceeded that of the ORM2 variant. No sex-related differences were observed in respect either in the total AAG level nor the relative proportions of the ORM1 and ORM2 variants. The data collected in this study may serve as a reference towards the investigation of possible changes in the expression of the genetic variants of AAG in chronic inflammatory diseases.

Alpha-tocopherol and bilirubin antioxidant properties were evaluated in sickle cell disease. The total peroxyl radical trapping antioxidant activity of plasma (TRAP) was measured with a polarographic method using hemin as oxidative stress initiator. The TRAP was not correlated with plasma alpha-tocopherol concentration. The TRAP was correlated with plasma total bilirubin concentration [TRAP = 8.1 (total bilirubin) +363.7 (r = 0.67)] and the correlation was even better with the sum (alpha-tocopherol + total bilirubin) plasma concentration [TRAP = 9.1(alpha-tocopherol + total bilirubin)+ 170.5(r = 0.77)]. The alpha-tocopherol contribution in the antioxidant capacity of plasma was significant but bilirubin level acted as the limiting factor of plasma antioxidant capacity in sickle cell anemia. This result can be explained by the antioxidant property of bilirubin but also by coantioxidant activity towards oxidized alpha-tocopherol.

Inhibition of binding of the labelled antagonist (-)[3H]CGP 12177 by the full agonist (-)isoproterenol results in shallow competition curves, characteristic of the presence of both high- and low-affinity states of beta-adrenoceptors (betaAR). When in excess, the GTP analog 5'-guanylylimidodiphosphate (GppNHp) is expected to convert all receptors in the high-affinity state to the low-affinity state. However, in the rat cortex and cerebellum synaptosomes, a proportion of the betaAR in the high-affinity state was GppNHp-insensitive. This apparent GppNHp-insensitivity decreased with decreasing temperature of incubation. Moreover, it was totally abolished by the gentle treatment of membranes with 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS). We propose that a protein factor interacts with the betaAR/Gs protein complex and that it induces the GppNHp-insensitivity. This factor would be released by CHAPS in a functional form because it may regenerate the GppNHp-insensitivity after concentration and reconstitution with CHAPS-treated membranes. It is likely that the factor acts as a stabiliser of betaAR in the high-affinity state.

THE REASONED choice of a drug results from the double evaluation of the expected benefit and the subsequent therapeutic risks. This becomes obviously more complicated when several drugs have to be given in combination for better effectiveness, as is the case for transplant patients. Therapeutic risks are therefore increased because either the side effects are the same in nature and act synergistically, or they simply become more numerous. They are also enhanced when drug indications coincide with particular conditions, one of them being pregnancy, which no doubt becomes a condition at risk in all transplant women. One has then to face the triple challenge to combine successfully altogether a right level of immunosuppression, a pregnancy that would work out normally, and the absence of fetal damage. A specific procedure does not exist today to systematically study what could be entitled a school's case of pharmacology. In fact, immunosuppressive treatments are established most of the time on the basis of empirical results, which means that there is only a narrow margin left for an attempt to modify therapeutic protocols that have been already stated that way. Immunosuppressant drugs also frequently, even constantly, develop side effects such as renal insufficiency and hypertension in the mother and prematurity in the fetus. With that in mind, we here will state the pharmacological basis for the use of immunosuppressants in posttransplant pregnant women, in order to provide not only for the mother's safety but also to prevent both the fetus (F1) and second generation (F2) from drug injury. In that view, we have designed a step-by-step critical analysis that addresses the various pharmacological parameters of immunosuppressants that may be used during pregnancy. Our evaluation has been made on the basis of toxicologic, pharmacodynamic, and pharmacokinetic criteria in the light of pregnancy itself and its most frequently associated pathological states.

The binding and characteristics of rat brain beta-adrenergic receptors (beta-AR) isolated from astrocytes and neurons were investigated. Equilibrium binding experiments demonstrated that beta-AR were more concentrated on astrocytes than on neurons isolated from forebrain, cerebral cortex and cerebellum. Inhibition experiments revealed that beta 1-AR and beta 2-AR were present in the two cell types. Isoproterenol revealed two interchangeable states of high and low affinity binding to both beta 1- and beta 2-AR in neurons. The high affinity binding sites were sensitive to guanylylimidodiphosphate (GppNHp). Similar results were found with other beta-AR agonists but not with salbutamol and salmeterol which recognized both affinity states of the neuronal beta 2-AR but only the low affinity state of beta 1-AR. In astrocytes only the low affinity state of beta-AR was observed.

To obtain a pharmacologic effect of melatonin in rats kept under prolonged continuous light exposure, conditions known to produce functional suppression of the circadian system, mimicking of the physiologic 24-h pattern of melatonin secretion, a hormonal signal of darkness exposure may be needed. The delivery scheme for melatonin was established in rats in the present studies. First, the plasma pharmacokinetics of [3H]melatonin were determined in rats kept under continuous light and in rats synchronized by exposure to alternating 12 h light and 12 h darkness (LD 12:12) in the early light span. The pharmacokinetics of total radioactivity were similar in both groups. Further quantitation of melatonin by thin-layer chromatography revealed differences dependent on light conditions. The mean plasma clearance and steady-state distribution volume were approximately twice as low with continuous light as with LD 12:12. Plasma protein binding of melatonin was approximately 33%, irrespective of group or sampling time. These pharmacokinetic parameters were used to devise a 24-h periodic delivery schedule consisting of a 6-h constant infusion of exogenous melatonin, followed by an 18-h melatonin-free interval. In a second study, the melatonin 24-h pattern was estimated from the measurement of 2-h fractions of urinary 6-sulfatoxymelatonin excretion for 4 days. 6 unrestrained rats kept under continuous light received melatonin for 2 days from 22:00 to 04:00 h through an indwelling jugular catheter, connected to a reservoir from a programmable pump. Only the administration of low doses (0.01 mg/kg/day) resulted in both a circadian pattern for 6-sulfatoxymelatonin excretion and normal physiological values during the infusion-free intervals. The resynchronizing efficacy of this schedule should be tested in rats with functional suppression of the circadian system.

□ Beyond their classical action on calcium channels, some calcium channel blockers also exhibit a calcium anti-ionophoretic effect. We studied this effect on respiratory control and Ca 2+ fluxes in a mitochondrial model to compare calcium antagonists chosen among three clinical classes: vascular, cardiac, and mixed effects. Synthetic calcium ionophore A23187 decreases respiratory control and modifies Ca 2+ fluxes. We show that calcium antagonists partially restore the parameters altered by A23187. By calculating the percentage of restoration, we found that vascular drugs exhibit a strong antiionophoretic effect, cardiac drugs exert no significant effect, and mixed calcium antagonists exert an intermediate effect. Thus, it appears possible to link the intensity of calcium anti-ionophoretic effect with the clinical interest of a calcium antagonist.

The interaction of isoproterenol with beta-adrenoceptors has been investigated in astroglial and neuronal cells isolated from adult rat cerebral cortices. Using the non-selective beta-adrenergic antagonist (3H)CGP-12177 as a ligand, binding experiments revealed that both types of cells exhibit beta-adrenoceptors. However the analysis of the isoproterenol displacement curve indicated that only neuronal cells contained the high affinity conformational state of the beta-adrenoceptor.

Fractionation of the three main genetic variants (F1, S and A) of human α1-acid glycoprotein (AAG), in their native (sialylated) form, by chromatography on immobilized copper(II) affinity adsorbent was investigated. This chromatographic method had been previously developed to fractionate the desialylated protein variants. For that purpose, the three main AAG phenotypes samples (F1S/A, F1/A and S/A), which had been previously isolated from individual human plasma samples, and an AAG sample from commercial source (a mixture of the phenotypes) were used in the native form. Affinity chromatography of these different samples on an iminodiacetate Sepharose—copper(II) gel at pH 7 resolved two protein peaks, irrespective of the origin of the native AAG sample used. The unbound peak 1 was found to consist of the F1, the S or both variants, depending on the phenotype of the AAG sample used in the chromatography. The bound peak 2 was found to consist of the A variant in a pure form. The fractionation results obtained with native AAG were found to be the same as those originally yielded by the desialylated protein. However, comparison of the interactions of native and desialylated AAG with immobilized copper(II) ions, using an affinity chromatographic method and a non-chromatographic equilibrium binding technique, respectively, showed that desialylation increased the non-specific interactions of the protein with immobilized copper(II) ions. The AAG variants were not fractionated when affinity chromatography was performed using immobilized zinc, nickel or cobalt(II) ions, instead of copper. After purification of each variant in the sialylated form (F1, S and A), their respective heterogeneity was studied by analytical isoelectrofocusing with carrier ampholytes in the pH range 2.5–4.5. In addition, the lectin-binding behaviour of the separate sialylated AAG variants was investigated by affinity chromatography on immobilized concanavalin A.

The three main desialylated variants (F1, S and A) of human α 1 -acid glycoprotein (AAG) a serum acute-phase reactant, were analysed by high-performance anion-exchange chromatography in order to determine their optimum separation conditions. The analysis consisted of three steps, as follows: (1) A desialylated commercial AAG was separated into one “fast”- and one “slow”-migrating fraction by preparative isoelectrofocusing. The “fast” and “slow” fractions were shown to contain the F1 variant and a mixture of the S and A variants, respectively. (2) The pH titration curves of these two fractions were then measured by strong anion-exchange chromatography with several buffer systems of increasing pH. From the data obtained, it was not possible to select the optimum conditions to separate the “fast” variant F1 from the “slow” variants A and S. However, the S and A variants were shown to ionize very differently. (3) The specific fractionation of the S and A variants was therefore carried out by anion-exchange chromatography under operating conditions based on the data obtained from the study of their pH titration curves. This was performed both with the “slow”-migrating fraction obtained by preparative isoelectrofocusing of commercial AAG and with an AAG (containing only variants S and A) purified from an individual serum on immobilized Cibacron Blue F3G-A. Identification of the fractionated proteins was achieved by analytical isoelectrofocusing.

We report a rapid method for the characterization of the human serum albumin (HSA) and alpha-1-acid glycoprotein (AAG) interactions with drugs. The binding of 1-anilino-8-naphthalene sulfonate (ANS) to AAG and HSA was measured by fluorescence spectroscopy. Fluorescence data indicated that ANS was bound tightly to at least one site on AAG, with an affinity constant of 1.35 x 10(6) M-1. The fluorescence of an ANS:AAG complex was quenched by the binding of various drugs. Fluorescence quenching of the HSA:ANS complex showed a single site with an affinity constant of 0.72 x 10(6) M-1. The interaction of AAG and HSA with ANS or other drugs was also studied by comparative equilibrium dialysis. [14C]Pipequaline was used as an AAG and HSA site marker. [14C]Pipequaline seems to share sites I (azapropazone) and II (diazepam and ibuprofen) of HSA. However, high concentrations of warfarin were unable to displace [14C]pipequaline. On the other hand, it was shown that palmitic acid decreased, whereas bilirubin increased the pipequaline binding.