Serotonin as a facilitatory neurotransmitter in the anticonvulsant activity of methaqualone.

Abstract

The neuromodulatory role of serotonin in the anticonvulsant activity of methaqualone was investigated. A dose-dependent increase in the ability of methaqualone to provide protection against pentylenetetrazol (90 mg/kg SC)-induced convulsions in mice was observed. The ED50 value for the anticonvulsant activity of methaqualone was calculated and found to be 60 mg/kg, IP. Pretreatment of mice with 5-hydroxytryptophan (100 mg/kg, IP, 2 hr) and p-chlorophenylalanine (300 mg/kg, IP, 2 hr), causing an increase in brain serotonin levels, resulted in a 60% and 80% increase, respectively, in the anticonvulsant activity of methaqualone. Similar pretreatment with p-chlorophenylalanine (300 mg/kg, IP, 48 hr), causing a lowering of brain serotonin, and methysergide (10 mg/kg, IP, 0.5 hr), causing blockade of brain serotonin receptors, resulted in a 40% and 20% decrease, respectively, in the ability of methaqualone to provide protection against pentylenetetrazol-induced convulsions. These results suggest a facilitatory role of serotonin in the anticonvulsant activity of methaqualone.

• Authors: M I Leadbetter, S S Parmar
• Journal: Physiology & behavior (Physiol Behav) Vol. 46 Issue 1 Pg. 105-6 (Jul 1989) ISSN: 0031-9384 [Print] United States
• PMID: 2530597 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anticonvulsants
• Receptors, Serotonin
• Serotonin
• Methaqualone
• Tryptophan
• 5-Hydroxytryptophan
• Fenclonine
• Pentylenetetrazole

Topics

• 5-Hydroxytryptophan (pharmacology)
• Animals
• Anticonvulsants
• Brain (drug effects)
• Dose-Response Relationship, Drug
• Fenclonine (pharmacology)
• Male
• Methaqualone (pharmacology)
• Mice
• Mice, Inbred Strains
• Pentylenetetrazole (pharmacology)
• Receptors, Serotonin (drug effects)
• Seizures (chemically induced, prevention & control)
• Serotonin (physiology)
• Tryptophan (pharmacology)