Effect of stress on the uptake of 3H-norepinephrine into rat myocardium.
Spontaneously beating atria from rats previously exposed to irregular, signalled footshock were incubated with 3H-norepinephrine. A significant reduction in the uptake and retention of radioactivity was found in the atria from stressed animals compared with unstressed controls. A kinetic study of the uptake process in both the stressed and control groups showed a similar Km value but a significantly different Vmax. It was concluded that the enhanced myocardial sensitivity to catecholamines previously reported can be explained in part, on the basis of an inhibition of neuronal uptake.
D000818:Animals; D001362:Avoidance Learning; D004597:Electroshock; D006325:Heart Atria / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D013312:Stress, Physiological / Q000378:metabolism*; D013997:Time Factors
D009638:Norepinephrine