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Fig. 1. The atrial action potential (AP) from isolated rainbow trout myocytes. AP
waveforms were elicited by current-clamp at a rate that corresponded to the
heart rate for rainbow trout in vivo at each temperature (0.6 Hz at
7°C, 1.0 Hz at 14°C and 1.4 Hz at 21°C). The steady-state APs from
6-10 cells at each temperature were averaged, and the resultant waveforms were
used to stimulate L-type Ca2+ channel current (ICa) and
sarcoplasmic reticulum (SR) Ca2+ accumulation in subsequent
experiments where the inter-pulse holding level was -80 mV.