ATP-dependence of 125I-insulin binding by rat soleus muscle.
Muscle ATP levels were lowered by incubating rat soleus muscles under anaerobic conditions, or in the presence of 2:4-dinitrophenol (0.5 mM), EDTA (5 mM) or mannitol (400 mM). 125I-insulin binding, measured under equilibrium conditions at 25 degrees C, was reduced by 49-71% in ATP-depleted muscles. Insulin binding was also determined using two other procedures which minimized internalization of 125I-insulin: these were (a) 5 min at 25 degrees C, and (b) 24 h at 3 degrees C. Under these conditions, 125I-insulin binding was reduced by 28-55% in ATP-depleted muscles. These results confirm that in soleus muscle the effect of ATP-depletion on 125I-insulin binding is actually concerned with the binding step itself and not merely a reflection of ATP-dependent internalization of the bound hormone.
D019297:2,4-Dinitrophenol; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D004140:Dinitrophenols / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D000860:Hypoxia / Q000378:metabolism; D066298:In Vitro Techniques; D007457:Iodine Radioisotopes; D007700:Kinetics; D008353:Mannitol / Q000378:metabolism; D009132:Muscles / Q000378:metabolism*; D051381:Rats; D011972:Receptor, Insulin / Q000032:analysis* / Q000187:drug effects; D013696:Temperature
D004140:Dinitrophenols; D007457:Iodine Radioisotopes; D008353:Mannitol; D000255:Adenosine Triphosphate; D004492:Edetic Acid; D011972:Receptor, Insulin; D019297:2,4-Dinitrophenol