abstract
- The possible interaction of melatonin with the GABAergic system at the receptor level was investigated. The effect of melatonin on the binding of the GABA agonist, [3H]muscimol, in crude synaptic membrane preparations was assayed. In fresh membrane preparations, melatonin increased [3H]muscimol binding in the rat striatum and frontal cortex. Treatment of membrane preparations with Triton X-100 appeared to abolish or depress the enhancing effect of melatonin. The use of Tris HCl as buffer appeared to be more effective than Tris-Citrate buffer suggesting a possible important ionic effect. The present findings suggest that melatonin is capable of enhancing [3H]muscimol binding in vitro, perhaps at the benzodiazepine-GABA-receptor-ionophore complex.