User:BusterTheBusta/4-Hydroxytryptamine

4-Hydroxytryptamine or 4-HT is a monoamine of the tryptamine class. It occurs in psilocybin-mushrooms as a necessary chemical precursor for the biosythesis of psilocybin, psilocin, baeocystin, norbaeocystin and aeruginascin. It is converted into these different compounds through a range of enzymes in psilocybin mushrooms, such as 4-hydroxytryptamine kinase found in psilocybe cubensis. It is a structural analog as well an isomer of serotonin, differening by the hydroxy-group being on the 4th position on the tryptamine structure, instead of the 5th.

Possible effects
These Effects are based on a small study from 1960 using one „intact“ cat, one „spinal“ cat, one dog and a rat


 * Blood pressure:  Cat, 4-HT (100µg/kg i.v.) produced a rise in blood pressure 2-6 times less intense but more sustained than the same dose of 5-HT.
 * Respiration:   Dog, 3-4µg/kg i.v. of 5-HT caused a transitory stimulation of respiration, eventually followed by hypopnea. 4-HT required a higher dosage than 5-HT and result was always respiratory depression.  Cat, both 5-HT and 4-HT caused bronchospasm. Effects of 4-HT at 100µg/kg i.v. were 2-4 times less intense but lasted longer than that caused by 5-HT.
 * Dog urinary bladder:  Stimulant action of 4-HT was approximately 2 times less intense than that of 5-HT, but was more sustained.
 * Diuresis of hydrated rats:  subcutaneous 4-HT showed only a poor antidiuretic effect. 6mg/kg were less effective than 0.04mg/kg 5-HT1.
 * Nictitating membrane:  4-HT was 2-5 times less active than 5-HT in contracting the nictitating membrane of the cat. The contraction by 4-HT lasted considerably longer.

Metabolism
After rats were given 4-HTP, a number of metabolites were found in their urine such as 4-HT as 4-HIAA.

Doses of 200mg, 500mg, 1000mg DL-4-HTP produce no pharmacological effects in man. 4-HIAA was the most abundant metabolite in the urine at 95-100mg after the 1000mg Dose, 53-55mg after 500mg and 22-24mg after 200mg. Only 1.3-2.2% of the administered amino acid was recovered aunchanged in the urine and less than 1% 4-HT.

Peaks were reached after 2 Hours at all Doses.

These results suggest that oral 4-HTP and the 4-HT originating from it are extensively metabolized by the intestinal wall and in the liver.