Supravital excitability of skeletal muscle of rats and bullfrogs to electrical stimuli.

Supravital excitability to electrical stimuli (for convenience, supravital electrocontractility (S.Ec) of the gastrocnemius muscle of rats and bullfrogs was examined after "somatic death" and the time during which S.Ec could be detected (S.Ec duration) was measured. S.Ec of the gastrocnemius muscle of rats and bullfrogs depended on temperature. The maximum S.Ec duration of the muscle of rats and bullfrogs were 110 min and 96 hr, respectively, at a low temperature (5 degrees), and 60 min and 9 hr, respectively, at a high temperature (30 degrees). The time course of rigor mortis at 5 degrees was slow and it was rapid at 30 degrees. In rats, the S.Ec disappeared completely before the onset of rigor mortis, and in bullfrogs, S.Ec existed at progressive stages of rigor mortis and it disappeared completely when rigor mortis reached about the maximum.