N- and P/Q-Type Ca²⁺ Channels Mediate Transmitter Release with a Similar Cooperativity at Rat Hippocampal Autapses

This work was supported by a Queen Elizabeth II Fellowship from the Australian Research Council (J.D.C.) and by a Grant from the Clive and Vera Ramaciotti Foundations (J.M.B.). C.A.R. was supported by a PhD scholarship from the John Curtin School of Medical Research. We thank Steve Redman, Greg Stuart, and Cathy Donaldson for helpful discussions and comments on this manuscript. We are grateful to Pfizer Central Research for its generous gift of ω-agatoxin IVA.

Correspondence should be addressed to John Clements at the above address.