Chronopharmacology of strychnine and allylglycine in the mouse

1. The response of individually caged mice to the lethal actions of allylglycine and strychnine was evaluated in animals previously conditioned on an LD 12:12 (12 h light-12 h darkness) schedule in a controlled environment. 2. These convulsant agents were most toxic at 18.00 hours (during the light phase), and least toxic in the dark phase of the programmed lighting schedule. The relationship is considered of the circadian fluctuations in levels of inhibitory transmitter substances to the time-linked action of convulsant agents.