Electrical Activity in Chick Amnion

¹ From the Department of Physiology, University of Illinois, Urbana, Illinois

Isolated amnions from chick embryos showed spontaneous electrical activity, both local and conducted. Responses to barium and to shocks were conducted at an average of 2.9 cm/sec. (38–40°C). Conducted responses were observed in amnions at 5–10 days of incubation. Failure of conduction in older amnions appears related to the shortening and increased randomness of the muscle fibers. This preparation gives conclusive proof of conduction in nerve-free smooth muscle.