Figure 3.

Injections of ACTH in vivo modulate the EOD waveform within minutes. Calibrated EODs were recorded approximately every 60 s from free-swimming fish and analyzed as described previously (Stoddard et al., 2003). A, Injections of saline caused little or no change in amplitude or duration (τ), whereas injections of ACTH caused rapid transient increases in both amplitude and τ. Insets show EOD waveforms sampled immediately before injection and 30 minafterinjection. B, Injections of ACTH (n = 6) increased both EOD amplitude (t = 4.53; df = 10; p < 0.01) andτ (t = 4.37; df = 10; p < 0.01) when compared with saline injections (n = 6). Circles, horizontal bars, and vertical bars represent individual data points, means, and SEM, respectively.