LSD, mescaline and serotonin injected into medial raphe nucleus potentiate apomorphine hypermotility
Heidrun Fink, Wolfgang Oelssner
European Journal of Pharmacology November 1, 1981 DOI: 10.1016/0014-2999(81)90556-2 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Rats |
| Interventions | LSD mescaline serotonin methysergide cyproheptadine apomorphine |
| Dose | LSD 0.05 microgram, mescaline 0.5 microgram, serotonin 10 microgram, methysergide 0.05 microgram, cyproheptadine 0.05 microgram, apomorphine 1 mg/kg i.p. |
| Topics | Mescaline Serotonin LSD |
| Keywords | Apomorphine Dorsal raphe nucleus Raphe nuclei Median raphe nucleus Cyproheptadine Methysergide Nucleus accumbens Microinjections Pharmacology Hallucinogen Endocrinology |
| Citations | 44 |
| Key findings | Microinjections of LSD, mescaline, and serotonin into the medial raphe nucleus potentiate apomorphine-induced hypermotility, which is blocked by serotonergic antagonists, indicating the medial raphe nucleus is a key site for this effect. |
Abstract
Microinjections of LSD (0.05 microgram), mescaline (0.5 microgram) and serotonin (10 microgram) into the medial raphe nucleus of rats resulted in a strong potentiation of apomorphine (1 mg/kg i.p.)-induced hypermotility. The potentiating effect of LSD or serotonin was suppressed by simultaneous injections of methysergide (0.05 microgram) or cyproheptadine (0.05 microgram) into the medial raphe nucleus. The same doses of LSD injected into the dorsal raphe nucleus and of LSD and mescaline injected into the nucleus accumbens failed to influence locomotor activity, whereas injections of higher doses of LSD and mescaline into the nucleus accumbens inhibited spontaneous and apomorphine-stimulated locomotor activity. It is concluded that the potentiating effect of systemically administered low doses of hallucinogens was triggered by preferential actions on the serotonergic system in the medial raphe nucleus.
Comparable studies
Other preclinical and animal studies on mescaline, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Correlation between the potency of hallucinogens in the mouse head-twitch response assay and their behavioral and subjective effects in other species. C57BL/6J mice | 2020 | Experimental study with dose-response experiments | |
| Brain mechanisms of hallucinogens and entactogens Humans and rats | 2001 | Review | |
| Effects of hallucinogenic agents mescaline and phencyclidine on zebrafish behavior and physiology Zebrafish (Danio rerio) | 2012 | Experimental study | |
| Lysergic Acid Diethylamide- and Mescaline-Induced Attenuation of the Effect of Punishment in the Rat Rats | 1976 | Experimental study | |
| Dihydrobenzofuran Analogues of Hallucinogens. 3. Models of 4-Substituted (2,5-Dimethoxyphenyl)alkylamine Derivatives with Rigidified Methoxy Groups Rats (trained to discriminate saline from LSD tartrate) and rat cortical and... | 1996 | In vivo drug discrimination assay and in vitro radioligand binding assay |
Citations in the library
Cited by 3
- Behavioral effects of intracerebroventricular administration of LSD, DOM, mescaline or lisuride Pharmacology, Biochemistry, and Behavior August 1, 1984
- Psychedelics and Reward Processing: Before and After the 1970 Controlled Substances Act Psychedelic Medicine July 24, 2026
- Phencyclidine-induced head-weaving and head-twitch through interaction with 5-HT1 and 5-HT2 receptors in reserpinized rats. Neuropharmacology October 1987
Cites 3
- Lysergic acid diethylamide: Role in conversion of plasma tryptophan to brain serotonin (5-hydroxytryptamine) Science 1969
- Dissociations Between the Effects of LSD on Behavior and Raphe Unit Activity in Freely Moving Cats Science August 3, 1979
- Psychotomimetics potentiate locomotor hyperactivity induced by dopaminergic drugs. Pharmacology, Biochemistry, and Behavior November 1979