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Using the micronucleus test as a screening method for mutagenic activity, no significant increase in the number of micronuclei was found when LSD, psilocybin or delta 9-THC were administered in 3 logarithmically increasing doses to mice, Azathioiprine (Imuran), given as a positive control, caused a statistically significantt increase in the micronucleated cells.
RATIONALE: Serotonin (5-Hydroxytryptamine, 5-HT) receptors play an important role in perception, affect regulation and attention. Pharmacological challenge with the 5-HT(2A) agonist psilocybin (PY) is useful in studying the neurobiological basis of cognition and consciousness. OBJECTIVE: Investigation of dose-dependent effects of PY on psycho(patho)logical and physiological parameters. METHODS: Eight subjects received placebo (PL), and 45 ("very low dose, VLD"), 115 ("low dose, LD"), 215 ("medium dose, MD"), and 315 ("high dose, HD") microg/kg body weight PY. The "Altered States of Consciousness Rating Scale" (5D-ASC), the "Frankfurt Attention Inventory" (FAIR), and the "Adjective Mood Rating Scale" (AMRS) were used to assess the effects of PY on psycho(patho)logical core dimensions, attention, and mood. A 24-h electrocardiogram (EKG) was recorded and blood pressure was measured. Plasma concentrations of thyroid-stimulating hormone (TSH), prolactin (PRL), cortisol (CORT), adrenocorticotropic hormone (ACTH), and standard clinical chemical parameters were determined. RESULTS: PY dose dependently increased scores of all 5D-ASC core dimensions. Only one subject reacted with transient anxiety to HD PY. Compared with PL, MD and HD PY led to a 50% reduction of performance in the FAIR test. "General inactivation", "emotional excitability", and "dreaminess" were the only domains of the AMRS showing increased scores following MD and HD PY. The mean arterial blood pressure (MAP) was moderately elevated only 60 min following administration of HD PY. Neither EKG nor body temperature was affected by any dose of PY. TSH, ACTH, and CORT plasma levels were elevated during peak effects of HD PY, whereas PRL plasma levels were increased following MD and HD PY. CONCLUSION: PY affects core dimensions of altered states of consciousness and physiological parameters in a dose-dependent manner. Our study provided no cause for concern that PY is hazardous with respect to somatic health.
Using thin-layer chromatographic and spectroscopic (UV) methods two Psilocybe species from the Venezuelan Andes were analysed for the hallucinogens psilocybin and psilocin. These species are: P. montana (Pers. ex Fr.) Kumm and P. pseudobullacea (Petch) Pegler. Both hallucinogens were found in P. pseudobullacea, while P. montana was found to be exempt of these compounds.
An SAR study of psilocybin and psilocin derivatives reveals that 1-methylpsilocin is a selective agonist at the h5-HT(2C) receptor. The corresponding phosphate derivative, 1-methylpsilocybin, shows efficacy in an animal model for obsessive-compulsive disorder, as does 4-fluoro-N,N-dimethyltryptamine. These results suggest a new area for development of novel 5-HT(2C) agonists with applications for drug discovery.
In order to investigate the pharmacokinetic properties of psilocybin (PY), the main psychoactive compound of Psilocybe mushrooms, high performance liquid chromatographic procedures with column-switching coupled with electrochemical detection (HPLC-ECD) for reliable quantitative determination of the PY metabolites psilocin (PI) and 4-hydroxyindole-3-acetic acid (4HIAA) in human plasma were established. Sample work-up includes protection of the highly unstable phenolic analytes with ascorbic acid, freeze-drying and in-vitro microdialysis. The data of two controlled clinical studies with healthy volunteers are presented. The subjects (N = 6 for both studies) received single oral PY doses of 0.224 +/- 0.02 mg/kg b.wt. (10-20 mg) and intravenous doses of 1 mg PY, respectively. Peak plasma levels of PI after oral administration of PY were measured after 105 +/- 37 min showing an average concentration of 8.2 +/- 2.8 ng PI/ml plasma. 4HIAA peak concentrations of 150 +/- 61 ng/ml plasma were found 113 +/- 41 min after ingestion of PY. After intravenous administration, a mean PI maximum plasma concentration of 12.9 +/- 5.6 ng/ml plasma was found 1.9 +/- 1.0 min after injection. The maximum plasma levels appearing within a very short period indicate a rapid dephosphorylation of PY also when administered systemically. 4HIAA was not detected after 1 mg of intravenous PY. Estimates for the absolute bioavailability of PI after oral administration of PY were 52.7 +/- 20% (N = 3).
In a clinical study eight volunteers received psilocybin (PY) in psychoactive oral doses of 212+/-25 microg/kg body weight. To investigate the elimination kinetics of psilocin (PI), the first metabolite of PY, urine was collected for 24 h and PI concentrations were determined by high-performance liquid chromatography with column switching and electrochemical detection (HPLC-ECD). Sample workup included protection of the unstable PI with ascorbic acid, freeze-drying, and extraction with methanol. Peak PI concentrations up to 870 microg/l were measured in urine samples from the 2-4 h collection interval. The PI excretion rate in this period was 55.5+/-33.8 microg/h. The limit of quantitation (10 microg/L) was usually reached 24 h after drug administration. Within 24 h, 3.4+/-0.9% of the applied dose of PY was excreted as free PI. Addition of beta-glucuronidase to urine samples and incubation for 5 h at 40 degrees C led to twofold higher PI concentrations, although 18+/-7% of the amount of unconjugated PI was decomposed during incubation. We conclude that in humans PI is partially excreted as PI-O-glucuronide and that enzymatic hydrolysis extends the time of detectability for PI in urine samples.
The concise large-scale syntheses of psilocin (1) and psilocybin (2), the principal hallucinogenic constituents of "magic mushroom", were achieved without chromatographic purification. The key step in the synthesis of 2 was the isolation of the dibenzyl-protected intermediate (7) as a zwitterionic derivative (8), which was completely identified by means of 2D NMR analyses.
Binocular rivalry occurs when different images are presented simultaneously to corresponding points within the left and right eyes. Under these conditions, the observer's perception will alternate between the two perceptual alternatives. Motivated by the reported link between the rate of perceptual alternations, symptoms of psychosis and an incidental observation that the rhythmicity of perceptual alternations during binocular rivalry was greatly increased 10 h after the consumption of LSD, this study aimed to investigate the pharmacology underlying binocular rivalry and to explore the connection between the timing of perceptual switching and psychosis. Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine, PY) was chosen for the study because, like LSD, it is known to act as an agonist at serotonin (5-HT)1A and 5-HT2A receptors and to produce an altered state sometimes marked by psychosis-like symptoms. A total of 12 healthy human volunteers were tested under placebo, low-dose (115 microg/kg) and high-dose (250 microg/kg) PY conditions. In line with predictions, under both low- and high-dose conditions, the results show that at 90 min postadministration (the peak of drug action), rate and rhythmicity of perceptual alternations were significantly reduced from placebo levels. Following the 90 min testing period, the perceptual switch rate successively increased, with some individuals showing increases well beyond pretest levels at the final testing, 360 min postadministration. However, as some subjects had still not returned to pretest levels by this time, the mean phase duration at 360 min was not found to differ significantly from placebo. Reflecting the drug-induced changes in rivalry phase durations, subjects showed clear changes in psychological state as indexed by the 5D-ASC (altered states of consciousness) rating scales. This study suggests the involvement of serotonergic pathways in binocular rivalry and supports the previously proposed role of a brainstem oscillator in perceptual rivalry alternations and symptoms of psychosis.
Psilocybin, a hallucinogen, formed a blue color with a subfraction of rat-brain mitochondria believed to contain nerve-ending particles. Color formation increased with pH, did not require oxygen, and involved a component that could not be solubilized. The effect was not shown by chemically related neuroactive compounds, such as bufotenine and serotonin, and was antagonized by only tyramine or ethylenediaminetetraacetic acid.
1 We have reviewed the clinical features and management of 44 consecutive patients presenting to hospital over a 5 week period during an outbreak of ingestion of psilocybin containing mushrooms. 2 Patients presented to hospital usually because of dysphoric effects an average of 3.8 h after ingesting mushrooms. 3 Mydriasis was present in 40 patients but fewer than half showed other sympathomimetic features--tachycardia, hypertension or hyperreflexia. 4 Twenty-three patients experienced nausea and vomiting. 5 Distortions of perception chiefly visual were frequent as were paraesthesiae and feelings of depersonalization. 6 The effects of the mushrooms were short-lived and had worn off within 12 h in all but one patient. 7 Inducing emesis did not appear to hasten recovery from the effects of the mushrooms.
The effects of the psilocybin, a psychomimetic substance, on mental junctioning were investigated in normal volunteers as well as in schizophrenics. The disturbances induced constitute a psychoneurotoxic syndrome--"a state of drunkenness"--of about four hours duration which develops in three distinct phases. The basic mental symptoms of this syndrome consist of disturbances of the apperception, sensory perception and emotion. A moderate impairment of egofunctioning or reality appraisal and an inability to integrate different mental processes are observed. The psychomotor behavior is mainly harmonized to the prevailing emotional state and to the experiences caused by perceptual alterations, in a lesser degree. These changes, according to our observations, are more severe and more "psychotic-like" in schizophrenics rather than in normals. Psychopathological analysis of these changes proves that the whole syndrome cannot be considered as related to the spontaneously triggered functional psychoses or to the organic ones and, therefore, the term "model-psychosis" according to our opinion, is unsatisfactory.
Accurate and sensitive analytical methods for psilocin (PC) and psilocybin (PB), tryptamine-type hallucinogens contained in "magic mushrooms," were investigated using liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS). The chromatographic separation on an ODS column and mass spectral information gave complete discrimination between PC and PB without derivatization. The mass spectrometric detection had a high sensitivity, and the tandem mass spectrometric detection provided more specificity and accuracy, as well as high sensitivity. The detection limits ranged from 1 to 25 pg by LC-MS in the selected ion monitoring mode, and the intra- and inter-day coefficients of variation were estimated to be 4.21-5.93% by LC-MS-MS in the selected reaction monitoring mode. By applying the present LC-MS-MS technique to four real samples, the contents of PC and PB were found to vary over a wide range (0.60-1.4 and 0.18-3.8 mg/g dry wt. for PC and PB, respectively) between samples.
A method has been developed for the analysis of psilocybin and psilocin in dry and preserved mushrooms using reversed-phase high performance liquid chromatography. A mobile phase of phosphate buffered methanol/water/cetrimonium bromide allows good separation of the two hallucinogens.
A method for isolating the main components (psilocybin and psilocine) from Psilocybe semilanceata mushrooms, their identification and measurement by thin-layer and gas-liquid chromatography, chromatographic mass-spectrometry, and inverse-phase high-performance liquid chromatography is developed.
The hallucinogenic mushroom Inocybe aeruginascens contains several typical Psilocybe alkaloids including psilocybin. We have now elucidated the structure of a further indole derivative named aeruginascin as the quaternary ammonium compound N, N, N-trimethyl-4-phosphoryloxytryptamine. Aeruginascin is closely related to the frog skin toxin bufotenidine (5-HTQ), a potent 5-HT3 receptor agonist, and has been found exclusively in Inocybe aeruginascens so far.
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