Inhibition of alpha oscillations through serotonin-2A receptor activation underlies the visual effects of ayahuasca in humans

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• 作者：Marta Valle^a ; ^b ; ^c ; ^d ; Ana Elda Maqueda^c ; ^e ; Mireia Rabella^c ; ^f ; Aina Rodrí ; guez-Pujadas^e ; Rosa Maria Antonijoan^b ; ^c ; ^d ; Sergio Romero^g ; ^h ; Joan Francesc Alonso^g ; ^h ; ⁱ ; Miquel À ; ngel Mañ ; anas^g ; ^h ; ⁱ ; Steven Barker^j ; Pablo Friedlander^k ; Amanda Feilding^k ; Jordi Riba^b ; ^c ; ^d ; ^e ; ^{jriba@santpau.cat" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Ayahuasca ; Serotonin-2A receptor ; Ketanserin ; Subjective effects ; Neurophysiological effects ; Human
• 刊名：European Neuropsychopharmacology
• 出版年：2016
• 出版时间：July 2016
• 年：2016
• 卷：26
• 期：7
• 页码：1161-1175
• 全文大小：3367 K

文摘

Ayahuasca is an Amazonian psychotropic plant tea typically obtained from two plants, Banisteriopsis caapi and Psychotria viridis. It contains the psychedelic 5-HT_2A and sigma-1 agonist N,N-dimethyltryptamine (DMT) plus β-carboline alkaloids with monoamine-oxidase (MAO)-inhibiting properties. Although the psychoactive effects of ayahuasca have commonly been attributed solely to agonism at the 5-HT_2A receptor, the molecular target of classical psychedelics, this has not been tested experimentally. Here we wished to study the contribution of the 5-HT_2A receptor to the neurophysiological and psychological effects of ayahuasca in humans. We measured drug-induced changes in spontaneous brain oscillations and subjective effects in a double-blind randomized placebo-controlled study involving the oral administration of ayahuasca (0.75 mg DMT/kg body weight) and the 5-HT_2A antagonist ketanserin (40 mg). Twelve healthy, experienced psychedelic users (5 females) participated in four experimental sessions in which they received the following drug combinations: placebo+placebo, placebo+ayahuasca, ketanserin+placebo and ketanserin+ayahuasca. Ayahuasca induced EEG power decreases in the delta, theta and alpha frequency bands. Current density in alpha-band oscillations in parietal and occipital cortex was inversely correlated with the intensity of visual imagery induced by ayahuasca. Pretreatment with ketanserin inhibited neurophysiological modifications, reduced the correlation between alpha and visual effects, and attenuated the intensity of the subjective experience. These findings suggest that despite the chemical complexity of ayahuasca, 5-HT_2A activation plays a key role in the neurophysiological and visual effects of ayahuasca in humans.