Figure 2
Effects of Iso on crucian carp heart. Concentration dependent effects of Iso on heart rate and atrial contractility in warm-acclimated and cold-acclimated crucian carp at the acclimation temperatures of the fish. Effect of Iso on heart rate and force of contraction (Fmax) (A) and on the duration of atrial contraction (DC) (B) in the absence and presence (inset) of 3·10-6 M timolol. Note the absence of responses to Iso. Results are means ± SEM of 15 and 17 fish for cold-acclimated and warm-acclimated fish, respectively.