Towards a better understanding of the psychopharmacology of nutmeg: Activities in the mouse tetrad assay

Ethnopharmacological relevanceNutmeg, the seeds of Myritica fragrans (family Myristicaceae), is a well known kitchen spice with a long-standing reputation as a psychoactive herb. Nutmeg at high doses is considered a cheap substitute to several drugs of abuse. Earlier reports have attributed amphetamine-like activities to nutmeg.Aim of the studyTo characterize the neuropharmacological effects of different nutmeg extracts, administered orally and intraperitoneally, in comparison to Δ9-terahydrocannabinol, amphetamine, and morphine.Materials and methodsMethanolic (ME), dichloromethane (DE), and hexane (HE) extracts were obtained from a chromatographically fingerprinted batch of nutmeg. Biological evaluation was conducted in sets of 6–8 mice in the tetrad assay at doses ranging from 100 to 500 and 500 to 1000 mg/kg for i.p. and oral administration, respectively.ResultsWhile oral administration of all the nutmeg extracts at 500 mg/kg caused a significant increase in locomotor activity, the i.p. administration of DE showed significant reduction in rectal temperature along with a significant increase in tail flick latency at 300 mg/kg. A significant decrease in core body temperature was observed with HE at 100 mg/kg, while higher doses caused significant increases in hot plate latency.ConclusionDifferent behavioral effects were observed that varied by the type of extract as well as by the route of administration.

Nutmeg, the seeds of Myristica fragrans (family Myristicaceae), is a well known kitchen spice with a long-standing reputation as a psychoactive herb. Nutmeg at high doses is considered a cheap substitute to several drugs of abuse. Earlier reports have attributed amphetamine-like activities to nutmeg. This study aimed at characterizing the neuropharmacological effects of different nutmeg extracts, administered orally and intraperitoneally, in comparison to Δ9-terahydrocannabinol, amphetamine, and morphine.While oral administration of all the nutmeg extracts at 500 mg/kg caused a significant increase in locomotor activity, the i.p. administration of DE showed significant reduction in rectal temperature along with a significant increase in tail flick latency at 300 mg/kg. A significant decrease in core body temperature was observed with HE at 100 mg/kg, while higher doses caused significant increases in hot plate latency. Accordingly, different behavioral effects were observed that varied by the type of nutmeg extract as well as by the route of administration.Figure optionsDownload as PowerPoint slide