Brain 5-hydroxytryptamine level, metabolism, and binding in E1 mice

Abstract

Inbred E1 mice are highly susceptible to convulsive seizures upon "throwing" stimulation. The strain is known to have an abnormal 5-hydroxytryptamine (5-HT) metabolism. In the study here 5-HT level, [14C]5-hydroxytryptophan (5-HTP) metabolism, MAO activity and [3H]5-HT receptor binding were examined in the cortex, brainstem and cerebellum. In the interictal period cortical and brainstem 5-HT level and [3H]5-HT receptor binding were significantly lower. In the same period cortical biosynthesized [14C]5-HT from [14C]5-HTP taken up was higher, and MAO activity was not changed. L-DOPA with MK486 induced a low threshold of seizures and decreased cortical 5-HT level. Abnormally functioning 5-HT neurones may exist in the E1 mouse cortex.

El Mouse as a Model of Focal Epilepsy: A Review

“…El cerebellar monoamine oxidase (MAO) activity levels were greater than those of Elo mice. Cortical and brainstem binding of [3H]-5-HT in the interictal period was lower in El mice than in Elo mice (Hiramatsu, 1983). Convulsions were completely inhibited and cortical 5-HT levels significantly elevated in El mice injected with piperine 60 mgkg.…”

Akitane Mori, the Artistic Neurochemist

“…Neurochemical studies in El mice by Akitane and his co-workers were initiated in the late 1970s, when a few pairs of El mice were donated from Imaizumi's colony, and were bred in Okayama University until Akitane's retirement. Akitane and his coworkers observed abnormalities of neurotransmitters such as acetylcholine, amino acids, amines, and their metabolites in the El mice brain [58][59][60][61][62][63][64][65][66]. Among them, abnormal changes of monoamines, i.e., serotonin, dopamine and norepinephrine, which are known to be inhibitory neurotransmitters or neuromodulators, may be due to the repetitive convulsions of El mice.…”