when tissue ph was regulated ectothermically ( as in cold-blooded animals ) ( delta ph/degrees c = -0.015 ) the heart maintained a stable pumping mode ( greater than 6 h ) at myocardial temperatures of 17-28 degrees c , ph = 7.70-7.55 , and heart rate of 25-50 bpm , respectively .
C0018787
heart
C0027061
myocardial