Hallucinogenic agents

A number of mushrooms, liberty cap (psilocybe), psilocybin, fly agaric, Amantia muscaria and the peyote cactus contain hallucinogenic agents. They are usually eaten raw but can be dried out and stored or cooked into food or made into a tea and drunk. The effects are highly variable and whereas 20-30 liberty caps would be required to give a full dose, just one fly agaric mushroom would produce similar actions. Some recent local surveys in the UK have found between 12% and 15% of 16-year-olds claiming to have used these at least once. 

Glennon, R.A. Rosecrans, J.A. and Young, R. Drug-induced discrimination A description of the paradigm and a review of its specific application to the study of hallucinogenic agents. Med Res Rev 3 289-340, 1983. 

Nair, X. Contractile responses of guinea pig umbilical arteries to various hallucinogenic agents. Res Commun Chem Pathol Pharmacol 9 535-542, 1974. 

Administration of hallucinogenic agents produces a number of distinct and apparently spontaneous motor responses in a variety of laboratory animals. These behaviors include the 5-HT syndrome in rats and mice, limb flicks in cats, and limb jerks in primates. These behaviors have in common (a) the apparently spontaneous (involuntary) nature of the response, and (b) the fairly well-established role of excitatory postsynaptic 5-HT receptor activation in the mediation of the effects. 

Glennon, R. A., Young, R., Rosecrans, J. A., and Kallman, M. J. (1980) Hallucinogenic agents as discriminative stimuli A correlation with serotonin receptor affinities. Psychopharmacology, 68 155-158. 

In summary, hallucinogenic agents produce the 5-HT syndrome in rats and mice by activating postsynaptic excitatory 5-HT receptors, many of which appear to be located in the brainstem and/or spinal cord. In addition, action of these agents at inhibitory 5-HT receptors may modulate the syndrome-producing effects of hallucinogens. 

IMPLICATIONS FOR THE USE OF THESE BEHAVIORS AS ANIMAL MODELS OF HALLUCINOGENIC AGENTS... 

The most potent of the known hallucinogenic agents is LSD. It is orally active in man at doses of about 0.1 mg (0.05 to 0.25 mg). The vast majority of human studies involving LSD and its structural variants were performed in the 1950s and 1960s and have been reviewed in great detail (24,154,196,208). Therefore, some of the key structure-activity relationships are briefly highlighted here only for the sake of completeness. 

Brimblecombe, R. W., and Pinder, R. M. (1975) Hallucinogenic Agents. Wright-Scientechnica, Bristol, Great Britain. 

Several mushrooms reported os hallucinogenic agents In Mexico. 

Weiss AJ, et al Dimethylacetamide A hitherto unrecognized hallucinogenic agent. Science 136 151-152, 1962... 

Like morphine, meperidine has an active metabolite, normeperidine, formed by A-demethylation of meperidine. Normeperidine is not analgesic but is a proconvulsant and a hallucinogenic agent. For this reason, meperidine use in patients with renal or fiver insufficiency is contraindicated because of the decreased clearance of the drug and its metabolite. Convulsant activity has been documented in elderly patients given meperidine and in patients using PCA who have decreased renal function. 

Illicit use of PCP as a hallucinogenic agent was first reported in San Francisco in 1967.1 It was first abused in oral form but then gained popularity in the smoked form as this mode of drug... 

Dana Farnsworth, M.D., "Hallucinogenic Agents, Editorial," Journal of the American Medical Association, 183,1963, pp. 878-80. 

Farnsworth, D. "Hallucinogenic Agents," editorial, Journal of the American Medical Association 185, 878-80,1963. 

Glennon RA. The role of serotonin in the mechanism of action of hallucinogenic agents. In Green AR, ed., Neuropharmacology of Serotonin. Oxford Oxford University Press. 

Brimblecombe and Pinder summarize the controversies in their Hallucinogenic Agents (1975) ... 

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