Neurotransmitter receptors in adult tottering (tg/tg) mice.

Neurotransmitter receptor binding was analyzed in adult tottering (tg/tg) and control wild-type mice. Saturation studies were performed to analyze the density of muscarinic cholinergic receptors in whole brain, cortical, and hippocampal homogenates of 8-9-week-old animals. Scatchard plot analysis was also performed to determine the density and affinity of alpha-adrenergic and beta-adrenergic receptors. No significant difference in Bmax or Kd values was identified between adult tottering and control mice in any of the tissue preparations. The amount of radioligand binding to 5-hydroxytryptamine 1A (5-HT1A), non-5-HT1A, 5-HT2, dopamine D2, and benzodiazepine receptors was also identical in tottering and control mice. These findings suggest that the epilepsy expressed by adult tottering mice does not result from alterations in the density or affinity of the neurotransmitter receptors studied.