Tolerance and limited cross-tolerance to the effects of N, N-dimethyltryptamine (DMT) and lysergic acid diethylamide-25 (LSD) on food-rewarded bar pressing in the rat.
Journal of Pharmacology and Experimental Therapeutics June 1, 1976 DOI: 10.1016/s0022-3565(25)30534-3 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Adult male Holtzman rats |
| Interventions | DMT LSD |
| Dose | 3.2 or 10 mg/kg DMT; 0.1 mg/kg LSD |
| Duration | 21 days of chronic DMT injections; 21 days plus 4 days of three-times-daily injections for LSD tolerance induction |
| Topics | LSD 5-MeO-DMT DMT |
| Keywords | Cross-tolerance Bar unit Food delivery Animal science Anesthesia Pharmacology |
| Citations | 33 |
| Key findings | Chronic DMT treatment produces tolerance to its disruptive effects on bar pressing, and cross-tolerance between DMT and LSD is asymmetrical, depending on the dosing regimen. |
Abstract
Lysergic acid diethylamide=25 (LSD) and N,N-dimethyltryptamine (DMT) abolish food-rewarded, fixed-ratio bar pressing by rats in a dose-related fashion. Adult male Holtzman rats trained to press a bar (respond) for milk reward on a 4-response fixed-ratio schedule were given i.p. injections of 3.2 or 10 mg/kg of DMT every 2 hours for 21 days. Every 24 hours the animals were placed in operant chambers for 30 minutes before a scheduled injection and were left in the chambers for 30 to 80 minutes after. During the first week of chronic treatment, daily bar pressing worsened progressively until the 6th day of the series, at which time rats in the 10 mg/kg group did not bar press at all. As the chronic injections continued, rates of bar pressing gradually increased until responding was not disrupted at all by an injection of DMT. Rats in the 3.2 mg/kg group showed cross-tolerance to an injection of LSD (0.1 mg/kg). Another group of rats was made partially tolerant to the disruptive effects of LSD (0.1 mg/kg i.p.) on bar pressing with a series of injections given once per day for 21 days and then three times per day for the next 4 days. Cross tolerance was not demonstrated to a challenge injection of 10 mg/kg of DMT. The LSD injections were continued for another 3 to 5 days until the animals were completely tolerant to the LSD. They then displayed cross-tolerance to 3.2 mg/kg of DMT.
Comparable studies
Other preclinical and animal studies on 5-MeO-DMT, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Psychedelic N,N-dimethyltryptamine and 5-methoxy-N,N-dimethyltryptamine modulate innate and adaptive inflammatory responses through the sigma-1 receptor of human monocyte-derived dendritic cells. Human primary monocyte-derived dendritic cells | 2014 | In vitro study | |
| Effects of N,N-Dimethyltryptamine on Rat Behaviors Relevant to Anxiety and Depression Adult male Sprague-Dawley rats | 2018 | Experimental study | |
| Hallucinogen-like actions of 5-methoxy-N,N-diisopropyltryptamine in mice and rats. Mice and rats | 2006 | Preclinical study | |
| Agonist Properties of N,N-Dimethyltryptamine at Serotonin 5-HT2A and 5-HT2C Receptors Rats and transfected fibroblasts | 1998 | Experimental study | |
| Subtypes of the 5-HT receptor mediating the behavioural responses to 5-methoxy-N,N-dimethyltryptamine in the rat Intact rats and rats depleted of monoamines with reserpine | 1985 | Experimental study |
Citations in the library
Cited by 18
- Neuropharmacology of N,N-dimethyltryptamine Brain Research Bulletin April 30, 2016
- Human psychopharmacology of N,N-dimethyltryptamine Behavioural Brain Research December 1, 1995
- Risk assessment of ritual use of oral dimethyltryptamine (DMT) and harmala alkaloids Addiction December 20, 2006
- Ayahuasca: Psychological and Physiologic Effects, Pharmacology and Potential Uses in Addiction and Mental Illness Current Neuropharmacology March 2, 2018
- Pharmacology of ayahuasca administered in two repeated doses Psychopharmacology August 12, 2011
and 13 more in the library