Neuroleptics from the 4a,9b-trans-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole series. 3. Carboxamidoalkyl derivatives

Substitution of position 2 of the 4a,9b-trans-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole nucleus with omega-carboxamidoalkyl substituents leads to compounds with exceedingly potent neuroleptic activity in in vitro and in vivo models. Although duration of activity is not as long as that of the analogous 4-hydroxy-4-(4-fluorophenyl)butyl derivatives reported previously, the absolute potency in vivo is greater. The ability of these compounds to bind with great affinity to dopamine (DA) receptors further defines the nature of the DA receptor auxiliary binding site as a hydrogen-bond donating site in addition to or instead of a lipophilic site as has been previously proposed.

Neuroleptic activity of chiral trans-hexahydro-gamma-carbolines

A series of trans-8-fluoro-5-(4-fluorophenyl)-2,3,4,4a,5, 9b-hexahydro-1H-pyrido[4,3-b]indoles with various N-2 substituents has been prepared and tested for neuroleptic activity [( 3H]spiroperidol binding and amphetamine antagonism). Several members of this series showed exceptional in vivo potency, especially the hydantoin derivatives 27-30. Resolution into the enantiomers showed that neuroleptic activity is associated with the 4aS,9bS absolute configuration. These rigid neuroleptics have been correlated with other rigid neuroleptics [(+)-dexclamol, Ro 22-1319] and can serve to further define the topography of the dopamine receptor.

Enhancement of brain [3H]flunitrazepam binding and analgesic activity of synthetic cannabimimetics

Novel, synthetic cannabimimetics and delta 9-tetrahydrocannabinol were found to enhance the binding of [3H]flunitrazepam to mouse brain in vivo. This property, suggestive of facilitation of binding to benzodiazepine receptors, is consistent with the potentiation of the anticonvulsant activity of diazepam against pentylenetetrazol by these compounds. The relative potencies of delta 9-tetrahydrocannabinol and the new cannabimimetics for enhancing [3H]flunitrazepam binding in vivo could also be correlated with their relative analgesic efficacies. Similar pharmacological stereospecificity was displayed for both binding enhancement and analgesic effects. The following order of decreasing potency was observed: N-methyllevonantradol and (-)-CP-55,244 greater than levonantradol, canbisol, CP-42,096 and (-)-CP-55,940 greater than 9-beta-normethyl-9-beta-hydroxyhexahydrocannabinol, nabilone and CP-47,497 greater than delta 9-tetrahydrocannabinol. Dextronantradol, (+)-CP-55,940 and (+)-CP-55,244 were considerably less active than the respective (-)-enantiomers; cannabidiol was inactive. Extensive investigation of structure versus activity led to N-methyllevonantradol and the 3-(2-hydroxyphenyl)cyclohexanols derivative, (-)-CP-55,244, which are approximately 1000-fold more potent than delta 9-tetrahydrocannabinol.

A cannabinoid derived prototypical analgesic

The synthesis and analgesic testing of 3-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]cyclohexanol (1) are described. Prior (SAR) studies led us to conclude that the pyran ring of 9-nor-9 beta-hydroxyhexahydrocannabinol (HHC) was not necessary for the expression of biological activity in this series of cannabinoids. Analysis of models and the use of molecular mechanics calculations suggested that a simpler compound, such as 1, would possess the biological activity of HHC. Compound 1 was prepared in nine steps from [3-(benzyloxy)phenyl]acetonitrile (2). Biological testing in five models of pain shows that compound 1 and morphine are equally potent as analgesics and demonstrates that the pyran ring of HHC is not necessary for biological activity. Further simplification of 1 was pursued by the synthesis of 4-[4-(1,1-dimethylheptyl)-2-hydroxyphenyl]-2-pentanol (17), but this derivative exhibits significantly reduced analgesic activity.

Sertraline, 1S,4S-N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthylamine, a new uptake inhibitor with selectivity for serotonin

Sertraline [1S,4S-N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthylamine] was found to be a highly selective and potent competitive inhibitor of synaptosomal serotonin uptake. Sertraline also selectively reduced ex vivo uptake of serotonin and strongly antagonized the serotonin-depleting action of p-chloroamphetamine, indicating potent blockade of serotonin uptake in vivo. Acute and repeated dosing of sertraline decreased serotonin content of whole blood. Sertraline only weakly inhibited rat heart uptake of i.v. [3H]norepinephrine. In substantiation of selective blockade of serotonin uptake, sertraline potentiated various symptoms of 5-hydroxytryptophan but did not reverse reserpine-induced hypothermia. Sertraline was a very weak inhibitor of [3H]quinuclidinyl benzilate binding to rat brain membranes in vitro and did not produce anticholinergic effects in mice in vivo. Sertraline was well tolerated in mice, rats and dogs, with no locomotor stimulant effects in rats or untoward cardiovascular effects in dogs. The major metabolite, N-demethylsertraline, was also a selective serotonin uptake blocker. Sertraline strongly reduced immobility of mice in the Porsolt swim test for antidepressants. After repeated dosing in rats, sertraline diminished the cyclic AMP response of limbic forebrain adenylate cyclase to norepinephrine, as well as the binding of [3H]dihydroalprenolol to cortical membranes. It is proposed that selective blockade of serotonin reuptake can induce activation of norepinephrine neurons and subsequent down-regulation of norepinephrine receptors and that sertraline, a highly selective inhibitor of serotonin uptake, may be an efficacious antidepressant without anticholinergic or cardiovascular side-effects.

An automated, high-capacity method for measuring jumping latencies on a hot-plate

A high-capacity automated apparatus for conducting analgetic screening in mice with an entirely objective endpoint is described. A thermostatically controlled hot-plate apparatus is interfaced with a minicomputer for recording jump latencies, which appear to reflect an affective component of pain. In a model experiment, morphine and naloxone were tested at four temperatures and at four times during the day. As expected, latencies were temperature-dependent, with no significant diurnal variation. The apparatus records latencies to both first and tenth jumps, providing a gross estimate of possible motor depressant effects. Morphine significantly increased latencies to first jump, but did not alter the time between first and tenth jumps, suggesting that motor depression did not occur.

Cannabimimetic activity from CP-47,497, a derivative of 3-phenylcyclohexanol

CP-47,497 (cis-3-[2-hydroxy-4(1,1-dimethylheptyl)phenyl]-cyclohexan-1-ol) is characterized as a cannabimimetic agent, with 3 to 28 times greater potency than delta 9-tetrahydrocannabinol delta 9-THC), based on the following. In common with delta 9-THC and other active structures closely related chemically to delta 9-THC, CP-47,497 exerts analgesic, motor depressant, anticonvulsant and hypothermic effects. It elicits vocalization in palpated rats and ataxia in dogs. In drug discrimination studies in rats, the stimulus properties of delta 9-THC (3.2 mg/kg i.p.) are generalized to CP-47,497, with an absolute threshold dose 3 to 14 times lower than the threshold dose of delta 9-THC itself, depending on route. Furthermore, rats are unable to discriminate between the stimulus properties of equated i.p. doses of delta 9-THC and CP-47,497 after prolonged training. Despite its potent behavioral effects, CP-47,497, like delta 9-THC, does not resemble standard antipsychotic, antidepressant, antianxiety or hypnotic drugs in simple drug interaction tests. Based on its pharmacology, CP-47,497 exemplifies a simplified structure capable of producing many effects in common with those of delta 9-THC and 9-normethyl-9 beta-OH-hexahydrocannabinol.

[Rectocolic lymph node appearance in adults (author's transl)]

A very characteristic rectocolic "lymph follicle appearance" was observed on radiological examination by double contrast enemas in 3.5 p. cent of 480 cases explored. The usual typical appearance is that of small lacunae of 1 to 3 mm in diameter, with indistinct borders, extending through several colon segments. The frequency with which these images are observed is probably a function of the double contrast technique employed, particularly the adherence of the barium. In most cases, the "lymph follicle appearance" is a variation of the normal, but several rare forms could result from a partial immunity deficiency. Differential diagnosis includes colon wall oedema and most polyposis disorders in their initial stages. Coloscopy with biopsy is necessary when diagnosis is uncertain.

GABA-like actions of levonantradol

The interaction of levonantradol and its pharmacologically less active (+)-enantiomer with GABAergic mechanisms was studied in several in vivo systems: (1) rat cerebellar cGMP, based on the inverse relationship of GABAergic activity and cGMP levels; (2) convulsions elicited by 3-mercaptopropionic acid, an inhibitor of GABA synthesis; and (3) activated dopamine synthesis in rat striatum following blockade of dopamine receptors. Levonantradol decreased rat cerebellar cGMP content at low doses (1.0 mg/kg intraperitoneally) and antagonized elevation of cGMP levels by the GABA biosynthesis inhibitor isoniazid at even lower doses (0.32 mg/kg intraperitoneally); this activity pattern is suggestive of GABAergic activity. This conclusion is also supported by levonantradol's protection of mice against the convulsant effects of 3-mercaptopropionic acid, GABAergic agents are known to antagonize the enhanced dopamine synthesis and turnover that accompany dopamine receptor blockade by neuroleptics. Levonantradol (0.047 mg/kg intravenously) stereospecifically attenuated the elevated dopa accumulation induced by haloperidol. Levonantradol is at least 100-fold more active than THC in blocking isoniazid-induced elevation of cGMP levels in rat cerebellum or haloperidol-induced enhanced dopa accumulation in rat striatum.

Discriminative stimulus properties of delta 9-tetrahydrocannabinol: mechanistic studies

delta 9-Tetrahydrocannabinol (THC) produces a multiplicity of pharmacologic effects including analgesic, antiinflammatory, anticonvulsant, antidiarrheal, antiglaucoma, antihypertensive, and sedative effects. Efforts to elucidate the neurochemical systems mediating the THC effects have used these and related endpoints. However, animal models useful for evaluating the mechanisms by which THC produces its unique subjective effects have only recently been established. The use of drugs as discriminative stimuli provides a means for studying such mechanisms, since generalization data from this test closely correlate with subjective properties observed in clinical studies. The present study examined the ability of various drugs to mimic or block the cue produced by THC in rats. In animals trained to discriminate 3.2 mg/kg THC from vehicle, generalization occurred consistently with cannabinoids such as 11-OH-THC, HHC, and nabilone. Stereoselective generalization was also obtained with isomers of a potent analgesic, nantradol; potencies were consistent with results from other endpoints. In contrast, THC cueing was not produced by agents acting on adrenergic, cholinergic, serotonergic, GABAergic, or opiate systems. Similarly, a number of drugs previously reported to antagonize various nonunique effects of THC uniformly failed to block its subjective properties. These results indicate that the subjective properties of THC are mediated through as yet unidentified neurochemical systems.

On the definition of cannabinoids: botanical? chemical? pharmacological?

Cannabinoids (or presumed synonyms such as cannabinols or cannabis-like agents) have been variously defined in botanical, chemical, or pharmacological terms, with unfortunate consequences. Botanical definitions include inactive substances such as cannabigerol, as well as alkaloids and other secondary constituents of Cannabis sativa, but exclude synthetics such as levonantradol and nabilone. Chemical definitions include inactive close analogs of THC but exclude a growing number of substances structurally remote from THC that share its actions. Pharmacological definitions have depended on relatively nonspecific or vague behavioral endpoints. However, animal testing methodology has recently been developed that can identify and quantify agents that share THC's unique subjective effects. To avoid preexisting ambiquity in the word cannabinoids, the term cannabimimetics has been coined to include all such agents, regardless of origin or structure. Such a classification emphasizes research toward improved biological selectivity and therapeutic advance. While no totally noncannabimimetic agents with potent analgesic effects have yet been identified among derivatives of THC, selectivity has been uncovered for levonantradol, HHC (racemic-9-nor, 9-beta-OH-hexahydrocannabinol) and several structurally related compounds.

Selective and potent analgetics derived from cannabinoids

Based on the hypothesis that analgetic activity is a dissociable feature of the cannabinoid molecule, we examined modifications of the side chain, the phenolic moiety, and, most significantly, structures that lack the benzopyran functionality present in THC and (--)-9-nor-9 beta-hydroxyhexahydrocannabinol (HHC). A new grouping, the 1-methyl-4-phenylbutyloxy C-3 side chain, elaborates a unique lipopholic region. Replacement of the phenol substituent produced several derivatives which retain analgetic activity in the codeine potency range. Introduction of a weakly basic nitrogen at C-5 and deletion of the axial methyl group in the B ring, two structural changes forbidden by traditional cannabinoid SAR, resulted in a unique family of benzoquinolines with potent analgetic activity. The prototype of this series, levonantradol, exhibits potent and stereospecific analgetic and antiemetic activity.

Facilitation of benzodiazepine binding by levonantradol

Levonantradol enhanced binding of 3H-diazepam to rat cortical membranes. Scatchard analysis of this effect showed apparent KD and Bmax changes at 100 microM levonantradol and a KD decrease at 50 microM. Dextronantradol caused a similar enhancement, suggesting a lack of stereospecificity in vitro. Subsequently, levonantradol at pharmacologic doses (0.15 mg/kg subcutaneously) was found to enhance the binding of intravenous 3H-flunitrazepam to mouse brain. In contrast to the results in vitro, dextronantradol showed no enhancement of 3H-flunitrazepam binding at doses up to 15 mg/kg subcutaneously. This stereospecific interaction with benzodiazepine receptors in vivo suggests that levonantradol may facilitate the pharmacologic actions of benzodiazepines. Levonantradol, at doses of 0.32 and 3.2 mg/kg subcutaneously, which did not block the convulsant effect of pentylenetetrazol, enhanced both the potency and efficacy of diazepam in elevating the absolute threshold of pentylenetetrazol for eliciting clonic seizures. Consistent with its lack of facilitation of benzodiazepine binding, dextronantradol at 3.2 mg/kg, a dose without effect on pentylenetetrazol-induced convulsions, showed little or no enhancement of diazepam's anticonvulsant activity against the latter.

4a,9b-trans-8-Fluoro-5-(4-fluorophenyl)-2-[4-(4-fluorophenyl)-4-hydroxybutyl]-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole hydrochloride, a new potent neuroleptic

The preparation and testing of the two racemic diastereoisomers and the four optically active enantiomers of the title compound in in vitro and in vivo models for determining potential antipsychotic activity are described. Both racemic diastereoisomers and two of the four chiral enantiomers are potent and long-acting neuroleptic compounds.

Neuroleptic 4-aryltetrahydropyrrolo[3,4-b]indoles

7-Fluoro-4-(4-fluorophenyl)-2-[4-(4-fluorophenyl)-4-hydroxybutyl]-1,2,3,4-tetrahydropyrrolo[3,4-b]indole displayed neuroleptic-like activity in an animal model approximately equipotent with that of chlorpromazine but was of substantially greater duration of action. Structure-activity relationships of the series are discussed.

Neuroleptic activity in 5-aryltetrahydro-gamma-carbolines

A series of 5-aryltetrahydro-gamma-carbolines was prepared by a novel N-arylation procedure and tested for neuroleptic activity in a rat antiamphetamine model. The systematic exploration of structural parameters leading to 8-fluoro-5-(4-fluorophenyl)-2-[4-hydroxy-4-(4-fluorophenyl)butyl]-2,3,5-tetrahydro-1H-pyrido[4,3-b]indole (CP-36,584, flutroline), a potent and long-acting neuroleptic compound, is described. These semirigid compounds provide a new, structurally distinct series with which to probe the conformational requirements for potent activity at the dopamine receptor.

[Radiological anatomy appearances of the colon after double contrast examination (author's transl)]

In this article, concerned with the normal radiological anatomy appearances of the colon after double contrast (mucography) examination, the authors develop the notion of an anteroposterior spatial disposition of the colon. Knowledge of the inclined zones, variable with incidence, in which the barium accumulates, is derived from this notion which appears, therefore, to be of practical value when performing or interpreting double contrast images. The second part of the article concerns a radiological study of the haustrations (blind sacs) and valves of the colon. This precise description of the three rows of haustral sacs could have topographical value in pathological conditions.

[Extra intestinal manifestations of Crohn's disease (author's transl)]

The extra intestinal manifestations of Crohn's disease (CD) are not devoid of interest. They can, by themselves, aggravate the CD. Some of them have to be searched systematically (urinary complications, spondylarthritis and sacro-iliac arthritis). Amongst our 60 cases of Crohn's disease of the colon or of the ileon and colon, articular manifestations were the most frequent: arthralgias 25 cases (42%), true arthritis 17 cases (28%), spondylarthritis 5 cases, aacro-ileitis 9 cas (13%), finger hippocratism 11 cases (18%). In second cause, the cutaneous manifestations: 29 cases (48%) among which 6 cases (10%) of erytheme nodosa and 9 cases of allergic troubles (15%). Then came ocular troubles (5 cases), jaundice (5 cases). We observed 4 renal lithiasis and an hepatic sarcoïd granuloma revealed by the liver biopsy. Some complications were the local consequence of a local disease (hydronephrosis). Others represented the distant repercussion of a severe chronical intestinal disease. Some were true extra-intestinal localisations of the disease (perineal ulcerations and para-stomal ulcerations). Finally some complications, though non specific of Crohn's disease, evolued in parallel to it (some articular, ocular; dermatologic complications). In some cases they were anterior by several months or years to the intestinal symptoms of Crohn's disease, which suggests the existence of common etiological factors, especially genetical.

[Findings by baryum enema in granulomatous colitis and ileocolitis. A review based upon 60 cases (author's transl)]

Radiological aspects of colonic involvement in 60 patients whose disease has been followed up during several years are described. The typical radiological findings have been observed with their usual frequency. This study also confirmed the persistancy of the radiological findings in the chronic stage and the frequency of recurence in the two first years after surgery. Extension of disease has not been uncommon in the series, even without surgery. This progression was different, according to the initial location of disease: in the case of initial ileal lesion, extension occurred towards the adjacent caecum and right colon in sequence; in the case of initial colitis or ileocolitis lesion, extension occurred at a distance in other colonic segments.