Behavioural Processes
June 6, 2015
Aline Pic‐taylor, Luciana Gueiros Da Motta, Juliana Alves de Morais et al.
99 citations
Ayahuasca, a psychoactive beverage containing DMT and β-carboline alkaloids, was administered to female Wistar rats at doses 15X, 30X, and 50X the typical ritual dose. The lethal oral dose exceeded 50X (15.1 mg/kg DMT). At 30X, ayahuasca reduced locomotion in open field and elevated plus-maze tests and increased swimming in the forced swimming test, suggesting antidepressant-like effects. Neuronal activation increased in serotonin-related brain areas, with some brain injury but no permanent damage. These findings indicate antidepressant properties at high doses, warranting further study.
Metabolic Brain Disease
February 27, 2020
Camila Schoueri Colaço, Stefany Sousa Alves, Luciana Marangni Nolli et al.
56 citations
Ayahuasca, a hallucinogenic beverage affecting the serotonergic system, was safe for rats after 28 days of oral treatment at doses up to twice the ritualistic dose, based on clinical, hematological, and macroscopic results. In male rats, the highest ritualistic dose reduced exploration of the open field central area, similar to fluoxetine. Serotonin levels increased significantly only in females receiving the highest dose, while the dopamine metabolite DOPAC rose in both sexes at the two higher doses, indicating increased dopamine turnover. Brain-derived neurotrophic factor (BDNF) in the hippocampus was significantly higher in females treated with fluoxetine or the highest ayahuasca dose. Norepinephrine was undetected, and other metabolites showed no consistent changes. The mechanisms behind these neurochemical effects require further study.
Chemico-Biological Interactions
August 4, 2018
Thayres S. Andrade, Rhaul Oliveira, Muriel Lopes Da Silva et al.
31 citations
Ayahuasca, a psychoactive brew made from Banisteriopsis caapi and Psychotria viridis plants and used ancestrally by Amazonian populations and more recently by religious groups, causes developmental toxicity and behavioral changes in zebrafish embryos and larvae. Over 96 hours of exposure at concentrations from 0 to 1000 mg/L, the LC50 was 236.3 mg/L. Exposure led to hatching delay, loss of equilibrium, edema, and red blood cell accumulation, mainly at the highest concentration. Locomotor activity in larvae decreased at the highest concentration tested. These results align with mammal studies and highlight possible risks of uncontrolled ayahuasca use.
Alcohol
November 4, 2019
Luciana Marangni Nolli, Danilo Gustavo Rodrigues de Oliveira, Stefany Sousa Alves et al.
28 citations
Ayahuasca, a hallucinogenic infusion used in religious rituals with serotoninergic properties, did not reduce ethanol intake in Wistar rats that had intermittent access to ethanol for 8 weeks when given at 0.5x, 1x, or 2x the ritual dose over the final 5 days. Naltrexone (2 mg/kg) modestly reduced intake compared to controls. Ethanol increased cFos expression in several brain regions, including the medial orbital cortex, ventral orbital cortex, lateral orbital cortex, and nucleus accumbens. Both naltrexone and the lowest ayahuasca dose decreased cFos in the medial orbital cortex relative to controls, but only ayahuasca brought expression to levels similar to a naïve group. Further studies are needed to clarify ayahuasca's effects on alcohol intake and its neural mechanisms.
Reproductive Toxicology
March 6, 2018
Luciana Gueiros Da Motta, Juliana Alves de Morais, Ana Carolina A.m. Tavares et al.
27 citations
Ayahuasca, when given orally to pregnant rats from gestation days 6 to 20 at doses one to eight times the average human ritual dose, caused maternal death and kidney injury at higher doses. Surviving rats at the highest dose showed neuronal loss in the hippocampus and raphe nuclei, and those at twice the human dose showed neuronal loss in the CA1 region. The highest dose also delayed intrauterine growth, increased embryo deaths, and raised the occurrence of fetal anomalies. At non-lethal doses, ayahuasca increased embryo deaths and the incidence of fetal soft-tissue and skeleton anomalies. The findings suggest ayahuasca is developmentally toxic and that daily use during pregnancy may pose risks to the developing offspring.
Revista Brasileira de Farmacognosia
March 9, 2017
Alana de Fátima Andrade Santos, Ana Luiza Sarkis Vieira, Aline Pic‐taylor et al.
19 citations
Chronic ayahuasca exposure in male Wistar rats reduced food intake and body weight gain at higher doses and increased relative brain and stomach weight at the highest dose. Total serum testosterone increased and sperm transit time and reserves in the epididymis caudae decreased at four times the ritualistic dose, but not at the highest dose. No effects were observed on sperm motility, morphology, total count, daily production, or testis and epididymis histology. The no-observed-adverse-effect-level for chronic and reproductive effects was two times the ritualistic dose, corresponding to 0.62 mg/kg bw DMT, 6.6 mg/kg bw harmine, and 0.52 mg/kg bw harmaline. A non-monotonic dose-response suggests potential toxicity at intermediate doses.