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Many of the addictive and rewarding effects of nicotine are due to its actions on the neuronal nicotinic ACh receptor (nAChR) subtypes expressed in dopaminergic mesocorticolimbic cells. The partial agonists, cytisine and varenicline, are helpful smoking cessation aids. These drugs have a number of side effects that limit their usefulness. The aim of this study was to investigate the preclinical pharmacology of the cytisine dimer1,2-bisN-cytisinylethane (CC4).The effects of CC4 on nAChRs were investigated using in vitro assays and animal behaviours.When electrophysiologically tested using heterologously expressed human subtypes, CC4 was less efficacious than cytisine on neuronal α4β2, α3β4, α7 and muscle-type receptors, and had no effect on 5-hydroxytryptamine3 receptors. Acting through α4β2 and α6β2 nAChRs, CC4 is a partial agonist of nAChR-mediated striatal dopamine release and, when co-incubated with nicotine, prevented nicotine's maximal effect on this response. In addition, it had low affinity for, and was less efficacious than nicotine and cytisine on the α3β4 and α7-nAChR subtypes. Like cytisine and nicotine, CC4-induced conditioned place preference (CPP), and its self-administration shows an inverted-U dose-response curve. Pretreatment with non-reinforcing doses of CC4 significantly reduced nicotine-induced self-administration and CPP without affecting motor functions.Our in vitro and in vivo findings reveal that CC4 selectively reduces behaviours associated with nicotine addiction consistent with the partial agonist selectivity of CC4 for β2-nAChRs. The results support the possible development of CC4 or its derivatives as a promising drug for tobacco smoking cessation.

Totally implantable venous access devices (TIVADs) are more and more used in oncologic patients. Early and late complications frequently occur with the techniques of implantation. Thrombosis is the most important and common late complication. On the opposite stenosis of the vessel is not frequently reported. The Authors report the case of a patient with subclavian vein stenosis after implantation of a TIVAD by percutaneous technique. On the basis of the published knowledges they try to explain this phenomenon and suggest an hypothesis for future works.

Nicotinic drug treatment can affect the expression of neuronal nicotinic acetylcholine receptors (nAChR) both in vivo and in vitro through molecular mechanisms not fully understood. The present study investigated the effect of the novel cytisine dimer 1,2-bisN-cytisinylethane (CC4) on nAChR natively expressed by SH-SY5Y neuroblastoma cells in culture. CC4 lacked the agonist properties of cytisine and was a potent antagonist (IC50=220 nM) on nAChRs. Chronic treatment of SH-SY5Y cells with 1 mM CC4 for 48 h increased the expression of 3H-epibatidine (3H-Epi; 3-4-fold) or 125I-alpha-bungarotoxin (125I-alphaBgtx; 1.2-fold) sensitive receptors present on the cell membrane and in the intracellular pool. Comparable data were obtained with nicotine or cytisine, but not with carbamylcholine, d-tubocurarine, di-hydro-beta-erythroidine or hexametonium. Immunoprecipitation and immunopurification studies showed that the increase in 3H-Epi-binding receptors was due to the enhanced expression of alpha3beta2 and alpha3beta2beta4 subtypes without changes in subunit mRNA transcription or receptor half-life. The upregulation was not dependent on agonist/antagonist properties of the drugs, and did not concern muscarinic or serotonin receptors. Whole-cell patch clamp analysis of CC4-treated cells demonstrated larger nicotine-evoked inward currents with augmented sensitivity to the blockers alpha-conotoxin MII or methyllycaconitine. In conclusion, chronic treatment with CC4 increased the number of nAChRs containing beta2 and alpha7 subunits on the plasma membrane, where they were functionally active. In the case of beta2-containing receptors, we propose that CC4, by binding to intracellular receptors, triggered a conformational reorganisation of intracellular subunits that stimulated preferential assembly and membrane-directed trafficking of beta2-containing receptor subtypes..

Two new cyclopentenylethylamines were prepared and were submitted to a pharmacological screening together with some others previously described and now reprepared. All compounds exhibited different degrees of depressive activity on CNS and good analgesic activity. Compound 5, bearing a phenyl group on the carbon atom to which the amino group is connected, appears rather interesting being the most active as analgesic and the least toxic. Compounds 2 and 3 are able to antagonize in a certain degree lethal doses of physostigmine and also, respectively, of pentylenetetrazole and strychnine.

On the ground of the evidentiated choleretic activity of 3-[2-benzylbenzimidazol-1-yl]butanoic acid, 28 new acids were prepared in order to evaluate the influence of suitable substitutions in either C5 of heteroring or C3', C4', C5' of benzyl group in position 2 on the choleretic activity. Pharmacological results after i.v. administration of 0.5 mmol/Kg in rats confirmed a general high choleretic activity that in eleven cases showed during the first 4 hours an increase of bile volume higher than 80%, that is superior to that produced by dehydrocholic acid. Only in a few cases the bile volume increase was less than 37% of basal value.

Pursuing our investigations on 7-amino-2,3-polymethyleneindole derivatives, a set of 7-(dimethylaminomethylene)-amino-2,3-polymethyleneindoles, together with some other aryl or cycloalkyl substituted formamidines, were prepared and tested for analgesic and antiinflammatory activities. Several compounds resulted endowed with one or both of these activities; the indole derivatives 1 and 2 exhibited a good degree of both of them.