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Despite a growing acceptance that withdrawal symptoms can emerge following discontinuation of cannabis products, especially in high-intake chronic users, there are no Food and Drug Administration (FDA)–approved treatment options. Drug development has been hampered by difficulties studying cannabis withdrawal in laboratory animals. One preclinical approach that has been effective in studying withdrawal from drugs in several pharmacological classes is antagonist drug discrimination. The present studies were designed to examine this paradigm in squirrel monkeys treated daily with the long-acting CB(1) agonist AM2389 (0.01 mg/kg) and trained to discriminate the CB(1) inverse agonist/antagonist rimonabant (0.3 mg/kg) from saline. The discriminative-stimulus effects of rimonabant were both dose and time dependent and, importantly, could be reproduced by discontinuation of agonist treatment. Antagonist substitution tests with the CB(1) neutral antagonists AM4113 (0.03–0.3 mg/kg), AM6527 (0.03–1.0 mg/kg), and AM6545 (0.03–1.0 mg/kg) confirmed that the rimonabant discriminative stimulus also could be reproduced by CB(1) antagonists lacking inverse agonist action. Agonist substitution tests with the phytocannabinoid ∆(9)-tetrahydrocannabinol (0.1–1.0 mg/kg), synthetic CB(1) agonists nabilone (0.01–0.1 mg/kg), AM4054 (0.01–0.03 mg/kg), K2/Spice compound JWH-018 (0.03–0.3 mg/kg), FAAH-selective inhibitors AM3506 (0.3–5.6 mg/kg), URB597 (3.0–5.6 mg/kg), and nonselective FAAH/MGL inhibitor AM4302 (3.0–10.0 mg/kg) revealed that only agonists with CB(1) affinity were able to reduce the rimonabant-like discriminative stimulus effects of withholding daily agonist treatment. Although the present studies did not document physiologic disturbances associated with withdrawal, the results are consistent with the view that the cannabinoid antagonist drug discrimination paradigm provides a useful screening procedure for examining the ability of candidate medications to attenuate the interoceptive stimuli provoked by cannabis discontinuation. SIGNIFICANCE STATEMENT: Despite a growing acceptance that withdrawal symptoms can emerge following the discontinuation of cannabis products, especially in high-intake chronic users, there are no FDA-approved pharmacotherapies to assist those seeking treatment. The present studies systematically examined cannabinoid antagonist drug discrimination, a preclinical animal model that is designed to appraise the ability of candidate medications to attenuate the interoceptive effects that accompany abrupt cannabis abstinence.

AM6538 is a cannabinoid antagonist that binds CB1 receptors expressed in HEK-293 cells in a wash-resistant manner. The effects of AM6538 in live animals has not previously been established. We characterized the antagonist effects of AM6538 in male mice, using a warm-water tail-withdrawal assay, and in male squirrel monkeys trained to discriminate the CB1 agonist AM4054 from vehicle. The cannabinoid agonists WIN 55,212, Δ(9)-tetrahydrocannabinol (THC), and AM4054 all produced 100% maximum possible antinociceptive effects in mice following vehicle pretreatment. One-hour pretreatment with increasing doses of AM6538 (0.1–10 mg/kg) produced first rightward, then downward shifts of the agonist dose-effect functions. Rimonabant, 1–10 mg/kg, produced parallel rightward shifts of the AM4054 dose-effect functions, and baseline effects of AM4054 were nearly recovered within 24 hours following 10 mg/kg of rimonabant. In contrast, in mice treated with 10 mg/kg of AM6538, antagonism of THC or AM4054 lasted up to 7 days. AM6538 also antagonized the discriminative stimulus effects of AM4054 in squirrel monkeys in a dose-related manner, and the effects of 3.2 mg/kg of AM6538 endured for more than 7 days. The effective reduction in CB1 receptor reserve was used to calculate the relative efficacy (tau values) of WIN 55,212, THC, and AM4054 in mice and of AM4054 monkeys, with results indicating that THC has a lower efficacy than WIN 55,212 or AM4054 in mice. These results demonstrate that AM6538 is a long-acting CB antagonist in vivo, and further suggest that differences in CB efficacy can be revealed in behavioral assays following AM6538 treatment.

The comparison of the composition of leukocytes of peripheral blood of healthy and Infected swine revealed the quantitative alterations, as well as the appearance of new cells in leukocyte population during African swine fever. It was determined that African swine fever virus induced mass-scale mortality of cells of peripheral blood, especially lymphocytes and neutrophiles. The number of the dead cells reaches 60% of the initial number of all cells at the end of infection. It was also revealed that the appearance of atypical lymphocytes and lymphoblasts was observed during viral Infections. Most of these cells are characterized by the presence of additional nucleus.

The authors studied the pathology of bone marrow (BM) lymphoid cell from pigs infected by African swine fever virus (ASFV) in vitro. Monocytes were shown to be primarily afflicted in unstimulated BM culture. These cells disappeared completely 72 hours after infection. Just 24 hours following ASFV infection, there were atypical lymphocytes amounting to 12% of the general lymphoid population at hour 72 after inoculation.The area and perimeter of minor, middle, and large lymphocytes tended to reduce during both BM cell cultivation and inoculation. Lymphoblasts and monocytes were generally triploid in both the control and test groups, but among them there were diploid, triploid, and tetraploid cells. Cytophotometric assay revealed that the amount of nuclear DNA significantly increased in BM lymphoblasts and monocytes in the early stages of ASFV infection (within 24 hours). This effect was also rather pronounced in the lymphoblasts in the later stages (at hour 72).

A new procedure is described for isolation of four forms of beta-endorphin from bovine pituitary. The four peptides are: the C-fragment of lipotropin (bovine lipotropin residues 63-93, or beta-endorphin, the alpha, N-acetyl derivative of the C-fragment, the C'-fragment (bovine lipotropin residues 63-89) and the alpha, N-acetyl derivative of the C'-fragment. Of these peptides, beta-endorphin alone possesses potent analgesic activity. The procedure has been applied in studying the distribution of beta-endorphin-related peptides in two regions of the pituitary. The results show that in the anterior pituitary of the pig and the rat, beta-endorphin is produced with a high degree of specificity in its opiate active form. In contrast, in the pars intermedia of both species at least six peptides related to beta-endorphin are elaborated and beta-endorphin represents only a minor component. The principal peptides in the pars intermedia have been identified as acetylated derivatives of lipotropin C'-fragment: in the pig the predominant peptide is alpha,N-acetyl C'-fragment and in the rat the major peptide appears to be an epsilon-acetylated derivative of alpha,N-acetyl C'-fragment. Thus, beta-endorphin is activated in the anterior pituitary and inactivated in the pars intermediate. The results demonstrate selective and specific processing of the 31K ACTH-endorphin prohormone in the different regions of the pituitary. In the anterior pituitary two biologically active peptides, ACTH and beta-endorphin, are generated together; in the pars intermedia alpha-melanotropin (alpha-MSH) is accompanied by forms of beta-endorphin that have been inactivated by acetylation and proteolysis.

Tomographic measurements of the 3D refractive index spatial distribution within optically transparent phase samples with computerized interferometric microscopes are proposed. Phase shifting interferometric microtomography applications for the 3D image reconstruction of the blood cells are represented. The immersion 100x, N.A. equals 1.25 objective was used to increase the spatial resolution and observation angle range to 90 degree. ART, combined ART and iterative Gerchberg-Papoulis 3D algorithm were used for the tomogram reconstruction. To determine the accuracy and spatial resolution of the blood cells image reconstruction by means of the interferometric microtomographic method the numerical simulations were implemented.

Measurements of refractive index spatial distribution within optically transparent phase 3-D samples with computerized interferometric microscopes is proposed. For the reconstruction of the phase information the phase shifting interferometry is used. Interferometric computed-tomography microscopes are fully automated integrated systems that incorporate CCD camera, frame grabber, computed operated PZT mirror as well as intelligible software for interferogram processing, tomographic reconstruction and refractive index distribution are displayed in 2-D and 3-D, sections, isolines, etc. Experimental results for interferometric microscopy and tomography of blood cells are presented.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The distribution of the C -terminal glycopeptide of the vasopressin prohormone was mapped in rat brain by an immunocytochemical method using antibodies to the sheep glycopeptide. The antibodies did not react with vasopressin, oxytocin or their related neurophysins. Stained neural perikarya were observed in the hypothalamus (suprachiasmatic, paraventricular, and supraoptic nuclei) and in the bed nucleus of the stria terminalis. Fibres were detected in the hypothalamus and in extrahypothalamic regions (the frontal cortex, the lateral septum, the bed nucleus of the stria terminalis, the medial nuclei of the thalamus, the lateral habenula, the amygdala, the mesencephalic central gray, the raphe nucleus of the solitary tract and the cervical spinal cord). The distribution of glycopeptide immunoreactive cells was generally similar in young rats (8 weeks old) to the distribution in older rats (13 weeks old) except in the bed nucleus of the stria terminalis where stained neurons were relatively sparse or absent in the younger animals. Similarly, in the young rats the density of fibres containing the glycopeptide was reduced in territories innervated by the bed nucleus. In both young and old rats the neuronal distribution of the glycopeptide was identical to the distribution of vasopressin, which suggests that the glycopeptide and vasopressin are co-transported from the sites of biosynthesis to the sites of release.

L'endometriose genitale est une maladie a problemes. Le diagnostic doit etre verifie non par voie chirurgicale mais par voie endoscopique. Le traitement hormonochirurgical conservateur bien conduit et bien indique, avant que ne s'installent des lesions sequellaires fibro-sclereuses extensives, donne d'excellents resultats, a condition que celui-ci soit precoce. L'endoscopie cependant, peut aussi etre source d'erreurs qui sont de veritables pieges que l'endoscopiste doit bien connaitre.

L’importance de la coelioscopie dans le cadre des investigations gynecologiques et en particulier dans la nevralgie pelvienne n’est plus a demontrer.

Enkephalin has been demonstrated in neurones in organotypic cultures of embryonic rat lumbar spinal cord using the indirect immunofluorescence technique. The peptide was demonstrated in neurone precursors in cultures of spinal cord at stage 16 (10 days' gestation). The subsequent development of the cells was studied by culturing spinal cord tissue from stage 30–34 (14–17 days' gestation) embryos and applying sequential immunocytochemistry, silver impregnation histology and autoradiography to the preparations. Acetylcholinesterase and γ-aminobutyrate transaminase activity in neurones and fibres in stage 30–34 cultures was at a maximum three weeks after explantation. Following a 24 h pulse of [ 3 H]thymidine, about one third of enkephalin-immunoreactive neurones were labelled in cultures 7 days old. The proportion fell to nearly zero in cultures 14 and 21 days old. At this time axonal and dendritic growth began in most immunoreactive cells. The disappearance of neuritic growth cones indicated that differentiation of the cells was not complete until 5–7 weeks after explanation. Fully-differentiated neurones had cell bodies of 10–15 μm diameter and processes spanning 400 μm or less. During development and at maturity, three groups of immunoreactive neurone were identified by morphological criteria. Immunocytochemical demonstration of leucine enkephalin-containing neurones in smear preparations of spinal cord from young animals suggested that their cytodifferentiation was also completed late in the process of development in vivo (after the second week of life). The results show that lumbar spinal neurones containing the putative transmitter, leucine enkephalin, have a prolonged but otherwise normal pattern of development when grown in tissue culture. When mature they appear to be small interneurones of several morphological types.

β-Endorphin is found in the pituitary with two related peptides, the C′-fragment (β-endorphin 1–27) and the des histidine derivative of the C′-fragment (β-endorphin 1–26) and each peptide occurs also in α, N-acetyl form. A chromatographic system is described which allows resolution of the six peptides extracted from rat pituitary. Evidence is presented that β-endorphin related peptides with similar chromatographic properties to the acetylated forms of β-endorphin are present as major components in rat pancreas and minor components in rat brain.

Six observations particulieres illustrent l’interet de l’oesophagoscopie precoce dans les ingestions de corps etrangers. L’extraction par l’endoscope evite bien souvent la thoracotomie.

Except in some extreme cases it is difficult to interpret the histological findings of ovarian biopsies per endoscopy in the gynecological functional disorders or in sterility of ovarian origin. We have tried to clarify this problem, here we report 100 observations and study 70 of them in two tables, for a better understanding, the correlation between anatomo-clinical aspects, histological pictures and results of ovarian stimulation suppression test by HCG Dexamethasone and Clomiphene Dexamethasone. This has permitted us to construct a chart of the histological results which would facilitate their interpretation.

The prohormone of beta-endorphin is unusual in that it is the precursor of more than one biologically active peptide (Fig. 1). The activation of this prohormone, to produce corticotropin (ACTH), alpha-melanotropin (alpha-MSH) and beta-endorphin, would seem to be relatively complex as its processing pattern is known to differ between tissues. Thus ACTH is produced in the anterior pituitary whereas alpha-MSH is formed in the pars intermedia; similarly, lipotropin and beta-endorphin seem to predominate in the anterior pituitary whereas beta-endorphin alone has been thought to be the principal component in the pars intermedia. We report here a study of the distribution of beta-endorphin-related peptides in various regions of porcine pituitary. The main products in the anterior pituitary were lipotropin and the potent analgesic form of beta-endorphin, whereas the main products in the pars intermedia were the inactive lipotropin C'-fragment and its N-acetyl derivative. Thus the processing of the C-terminal region of the beta-endorphin prohormone differs markedly between the two regions of porcine pituitary.

A propos de 54 cas de femmes sous contraceptif oral ou local nous analysons les interessantes perspectives de la colposcopie qui visualise certaines lesions non ou mal visibles a l'œil nu. L'association contraceptif oral et endometriose cervicale nous a parue a cet egard d'une assez grande frequence. Les micro traumatismes cervicaux du sterilet pourraient avoir une part dans le mecanisme etiologique de la greffe endometriosique sur le col.

Publisher Summary It has been known for several years that the C-terminal fragment of lipotropin possesses potent opiate properties and occurs naturally. Though it was first isolated from pituitary glands, it was soon realised that the 31 residue peptide, which has been named “β-endorphin”, is also present in brain where it is distributed in a manner typical of a neurotransmitter. More recently, it has been shown that β-endorphin can exist in a number of molecular forms, all of which show immunoreactivity with antibodies raised against β-endorphin. However, of these peptides, only β-endorphin exhibits potent analgesic activity; the C-fragment is 500 times less active and the acetylated peptides are inert. The experiments described here allow distinction to be made between the six β-endorphin related peptides and reveal that they are distributed differently in regions of brain.

Two novel peptides related to β-endorphin (1–31) have been isolated from porcine pituitary. One was identified as a des histidine form of the C′-fragment, corresponding to β-endorphin 1–26; the other was identified as an α,N-acetyl derivative of the des histidine C′-fragment. In displacing 3H-naloxone from rat brain synaptosomes, the 26 residue peptide in the NH2 form possessed a similar activity to the C′-fragment; the acetylated peptide did not possess specific opiate binding properties.

beta-Endorphin, the most potent known naturally occurring analgesic agent, is found in pituitary and brain in company with a series of structurally and biosynthetically related peptides that are essentially devoid of opiate activity. In studies of beta-endorphin it is important to discriminate between the active and inactive forms of the peptide. This review describes the use of chemical and immunological methods for localizing the peptides in the tissues, extracting and resolving the peptides by chromatography, and determining the concentrations of the peptides by radioimmunoassay. These approaches have allowed the distribution of beta-endorphin and its related peptides to be assigned unequivocally in regions of rat pituitary and brain. It has been found that the multifunctional corticotropin-endorphin prohormone can undergo processing by different mechanisms in different tissues, permitting the intrinsic activities of its fragments to be expressed selectively. The different processing patterns can be attributed to the existence of highly specific enzymes, characteristic of individual cells, which regulate the formation of this potent opiate.

Recent studies have shown that β-endorphin is found in the pituitary with two related peptides, the C′-fragment (β-endorphin1-27)1,2 and the des-histidine derivative of the C′-fragment (β-endorphin1-26)3, and that each of these peptides (Fig. 1) occurs also in an α,N-acetyl form3,4.The six peptides are derived from a single precursor by differential proteolytic cleavage and acetylation. The fact that different forms of β-endorphin predominate in different regions of the pituitary5,6 implies that there are region-specific differences in processing of the precursor. Because β-endorphin is known to occur widely in the brain7,8 as well as in the pituitary we have now investigated the distribution of the six peptides in selected regions of rat brain. We report here that, as in the pituitary, different regions of the brain contain strikingly different proportions of the six β-endorphin-related peptides, apparently as a result of differential processing.

SINCE the C-fragment of lipotropin (residues 61–91, β-endorphin) was found to occur naturally in the pituitary1,2 and brain3,4, the opiate-like properties of this peptide and its possible involvement in regulatory mechanisms in the central nervous system have been intensively studied. The C′-fragment of lipotropin (residues 61–87) also occurs in the pituitary1; it is a much less active opiate and has been little studied. We report here further experiments which reveal that in porcine pituitary the C-and C′-fragments are accompanied by substantial quantities of the corresponding α-N-acetyl peptides. The acetyl forms are inactive in opiate binding assays and in tests for analgesic properties but they retain the full immunological potency of the parent peptides.

A new procedure is described for isolation of four forms of beta-endorphin from bovine pituitary. The four peptides are: the C-fragment of lipotropin (bovine lipotropin residues 63-93, or beta-endorphin, the alpha, N-acetyl derivative of the C-fragment, the C'-fragment (bovine lipotropin residues 63-89) and the alpha, N-acetyl derivative of the C'-fragment. Of these peptides, beta-endorphin alone possesses potent analgesic activity. The procedure has been applied in studying the distribution of beta-endorphin-related peptides in two regions of the pituitary. The results show that in the anterior pituitary of the pig and the rat, beta-endorphin is produced with a high degree of specificity in its opiate active form. In contrast, in the pars intermedia of both species at least six peptides related to beta-endorphin are elaborated and beta-endorphin represents only a minor component. The principal peptides in the pars intermedia have been identified as acetylated derivatives of lipotropin C'-fragment: in the pig the predominant peptide is alpha,N-acetyl C'-fragment and in the rat the major peptide appears to be an epsilon-acetylated derivative of alpha,N-acetyl C'-fragment. Thus, beta-endorphin is activated in the anterior pituitary and inactivated in the pars intermediate. The results demonstrate selective and specific processing of the 31K ACTH-endorphin prohormone in the different regions of the pituitary. In the anterior pituitary two biologically active peptides, ACTH and beta-endorphin, are generated together; in the pars intermedia alpha-melanotropin (alpha-MSH) is accompanied by forms of beta-endorphin that have been inactivated by acetylation and proteolysis.

Peptides related to β-endorphin (residues 1–31)were extracted from rat pituitary and brain, resolved by chromatography and determined by RIA. In the pituitary, the biologically potent form of β-endorphin was the major immunoreactive peptide in the anterior region while the inactive acetylated forms of β-endorphin and C′-fragment (residues 1–27 and 1–26) were the major peptides of the pars intermedia. In the brain, the biologically potent form of β-endorphin was present in the hypothalamus as the major immunoreactive peptide; in the amygdala and mid brain it was accompanied by des histidine C′-fragment (β-endorphin 1–26). In the hippocampus, colliculae and brain stem, N-acetylated forms of the β-endorphin related peptides, which are inert as opiates, predominated. The results demonstrate the existence in these tissues of two distinct mechanisms for processing of the C-terminal region of the ACTH-endorphin prohormone.

IT is more than thirty years since Billingham and Medawar showed that adrenocorticotrophic hormone (ACTH) and cortisol can prolong the survival of skin allografts1,2. It has since become clear that glucocorticoid hormones are critically involved in the regulation of immunity3,4. The level of glucocorticoids secreted in response to antigenic challenge corresponds to the magnitude of the immune response and in general reaches immunosuppressive levels5–7. Interestingly, not all immune responses enhance ACTH and glucocorticoid hormone production. In transplantation immunity, the reverse seems to be true: circulating glucocorticoid levels at the time of skin graft rejection are lower than control levels8. Because β-endorphin and ACTH originate from the same prohormone, pro-opiomelanocortin (POMC)9, and are closely related in their tissue-specific processing and coordinate release10–12, we have investigated the role of pituitary β-endorphin in transplantation immunity. We report here that POMC biosynthesis and processing in the pars intermedia, but not in the anterior pituitary, can be regulated by T cell-specific factors secreted in animals undergoing transplantation immunity.

A polyoma virus-induced CB strain hamster tumour has been defined with regard to its immunogenetic specificity (§ 3.1) and evaluated as a convenient source of cells from which a crude but biologically active, strain-specific 9transplantation antigen’ can easily be pre­pared. This antigen is resistant to repeated freezing and thawing, lyophilization and sub­sequent storage at 5°C (§ 3.3). Although the extracted antigen elicited ‘ direct hypersensitivity ’ reactions when inoculated intracutaneously into MHA strain hamsters specifically presensitized against CB tissue antigens by means of skin homografts or lymphoid cellular inocula, it was incapable of inciting transplantation immunity in normal MHA hosts. However, when emulsified in complete Freund’s adjuvant and injected into the footpads of MHA recipients, the material was immunogenic as evidenced by ( a ) their accelerated rejection of subsequent test tumour or skin homografts, ( b ) their prompt rejection of skin homografts hitherto sustained in a privileged site, and ( c ) their capacity to give direct reactions when challenged intracutaneously with cells or antigen extract from CB strain donors (§ 3.4). Exposure of normal MHA lymphoid cells to CB antigen in vitro altered their behaviour in such a way as to suggest a prompt transformation to an ‘immune’ or specifically activated status—such cells, after careful washing, were capable of inciting ‘immune lymphocyte transfer’ reactions in the skins of MHA and (MHA x CB) F 1 hosts. However, various findings leave open the possibility that the sensitization actually took place in the skin of the host animal into which the cells were transferred after their exposure to the antigen in vitro (§ 3.7). Chronic treatment, over a 90-day period, of adult MHA hamsters with CB antigenic material administered intracutaneously and intraperitoneally, without adjuvant, induced a high degree of tolerance in respect of subsequent homografts of CB skin (§ 3.8).