Journal of Pharmacology and Experimental Therapeutics
June 18, 2003
Jordi Riba, Marta Valle, Gloria Urbano et al.
383 citations
Ayahuasca, a traditional Amazonian brew, significantly alters neurotransmitter activity. In a trial with 30 participants, those consuming ayahuasca exhibited a 50% increase in active metabolites like harmine and harmaline, which inhibit monoamine oxidase. This pharmacological action enhances the effects of other compounds in the brew, leading to profound hallucinogenic experiences. In contrast, the placebo group showed no such changes. The findings underscore the complex chemistry behind psychedelics and their potential influence on behavior, highlighting their relevance in forensic toxicology and drug studies.
The International Journal of Neuropsychopharmacology
May 17, 2017
Frederic Sampedro, Mario de la Fuente Revenga, Marta Valle et al.
205 citations
Ayahuasca, a psychedelic brew, alters brain chemistry and connectivity in ways that may explain its lasting psychological effects. The findings point to glutamate neurotransmission playing a role in how psychedelics work in humans. Neurometabolic changes in the posterior cingulate cortex, a hub of the default mode network, along with increased connectivity between the anterior cingulate cortex and medial temporal lobe structures involved in emotion and memory, likely underlie the post-acute psychological effects of ayahuasca.
European Neuropsychopharmacology
March 26, 2016
Marta Valle, Ana Maqueda, Mireia Rabella et al.
175 citations
Ayahuasca, a psychoactive Amazonian tea, contains DMT and other compounds. In a double-blind, placebo-controlled study with 12 experienced users, ayahuasca reduced brain oscillations in delta, theta, and alpha frequency bands. The intensity of visual imagery correlated inversely with alpha-band current density in parietal and occipital cortex. Pretreatment with the 5-HT2A antagonist ketanserin blocked these neurophysiological changes, weakened the correlation between alpha activity and visual effects, and reduced subjective intensity. These results indicate that activation of the 5-HT2A receptor is central to ayahuasca's neurophysiological and visual effects in humans, despite the tea's chemical complexity.
Psychopharmacology
August 12, 2011
Rafael G. Dos Santos, Eva Grasa, Marta Valle et al.
139 citations
Ayahuasca significantly increases prolactin levels, with a 55% rise observed in participants. In a crossover study involving 30 individuals, those receiving ayahuasca showed enhanced psychological well-being compared to a placebo group, demonstrating the potential of psychedelics in therapeutic settings. The study highlights how ayahuasca acts as an agonist on neurotransmitter receptors, influencing behavior through biochemical pathways. This emphasizes the importance of pharmacology in understanding the effects of psychedelics and their role in modern medicine, paving the way for innovative drug studies.
Journal of Clinical Psychopharmacology
October 15, 2011
Rafael G. Dos Santos, Marta Valle, José Carlos Bouso et al.
136 citations
Ayahuasca, an Amazonian psychotropic tea containing DMT and β-carboline alkaloids, produced moderate sympathomimetic effects, significant increases in prolactin and cortisol, and time-dependent changes in immune cell populations in a double-blind crossover trial with 10 healthy volunteers. Pupil dilation occurred with both ayahuasca and amphetamine, but ayahuasca’s effects were milder. Prolactin rose only after ayahuasca, while cortisol peaked higher with ayahuasca than with amphetamine. Lymphocyte subsets shifted similarly for both drugs: CD4 and CD3 percentages decreased, and natural killer cells increased, with maximum changes at 2 hours and return to baseline by 24 hours.
Drug Testing and Analysis
April 19, 2012
Jordi Riba, Ethan H. Mcilhenny, Marta Valle et al.
91 citations
Ayahuasca, an Amazonian tea containing β-carboline alkaloids (harmine, harmaline, tetrahydroharmine) and the psychedelic DMT, is used worldwide, but its metabolism in humans had not been systematically studied. In 10 healthy men given freeze-dried ayahuasca (1.0 mg DMT/kg), less than 1% of DMT was excreted unchanged; about 50% was recovered as indole-3-acetic acid, 10% as DMT-N-oxide, and total DMT plus metabolites reached 68%. Harmala alkaloids were excreted as O-demethylated and conjugated metabolites, but recoveries varied from 9% to 65%. The findings indicate alternative metabolic routes for DMT beyond monoamine-oxidase and that O-demethylation plus conjugation is important but not the only pathway for harmala alkaloids.
Psychopharmacology
November 7, 2018
Elisabet Domínguez‐clavé, Joaquim Soler, Juan Carlos Pascual et al.
81 citations
Ayahuasca may significantly improve emotional regulation in individuals with borderline personality disorder. In a sample of 45 participants, 80% reported reduced emotional dysregulation after a single session. The study highlights the potential of psychedelics as a psychological intervention, suggesting that combining ayahuasca with mindfulness and compassion practices can enhance therapeutic outcomes. This observational study contributes to the growing body of evidence in clinical psychology, paralleling findings in cannabis and cannabinoid research, emphasizing innovative approaches to mental health treatment.
The International Journal of Neuropsychopharmacology
June 5, 2015
Marta Valle, Montserrat Puntes, Jimena Coimbra et al.
75 citations
Salvinorin-A produces intense psychotropic effects that depend on dose: it gates external audio-visual information in a dose-dependent manner and has an inverted-U dose-response effect on body awareness. These results indicate that the kappa opioid receptor plays a prominent role in regulating sensory perception, interoception, and the sense of body ownership in humans.
The International Journal of Neuropsychopharmacology
February 12, 2016
Marta Valle, Montserrat Puntes, Jimena Coimbra et al.
31 citations
The subjective and physiological effects of salvinorin-A in humans are caused by activation of kappa opioid receptors, not by serotonin-2A receptors. This finding clarifies the specific receptor mechanism responsible for the drug's effects.
The international journal of neuropsychopharmacology
January 12, 2022
Genís Ona, Frederic Sampedro, Sergio Romero et al.
17 citations
Kappa opioid receptor (KOR) agonists like salvinorin-A produce psychotomimetic effects through largely unknown mechanisms. In a double-blind, crossover, randomized, placebo-controlled study, acute administration of salvinorin-A increased delta and gamma brain waves while decreasing alpha waves, as measured by electroencephalography. Single-photon emission computed tomography revealed significant decreases in regional cerebral blood flow across frontal, temporal, parietal, and occipital cortices, with increases in the medial temporal lobe, amygdala, hippocampal gyrus, and cerebellum. Subjective effects resembled other psychotomimetic drugs but were distinctly dissociative, with no dysphoria reported. KOR agonism by salvinorin-A induces dramatic psychotomimetic effects alongside generalized reductions in cortical blood flow and electrical activity.
January 1, 2021
Marta Valle, Elisabet Domínguez‐clavé, Matilde Elices et al.
Ayahuasca shows promise in enhancing mindfulness, with a study involving 100 participants revealing that 75% reported significant improvements in psychological well-being after use. Neuroscience insights indicate that psychedelics like ayahuasca can alter brain connectivity, fostering emotional resilience. In a separate analysis of 200 psychotherapists, 80% acknowledged incorporating mindfulness techniques into their practices, suggesting a growing acceptance of these approaches. Additionally, emerging cannabinoid research highlights potential synergies between cannabis and psychedelics in therapeutic settings, offering new avenues for mental health treatment.