Cooperative thermal effects on the accumulation of potassium and sodium in frog muscle.
Sodium-rich frog muscles are found to extrude sodium and reaccumulate potassium at 0 degrees C. The uptake of potassium by these muscles is studied at three different temperatures as a function of external potassium concentration, K(ex). The steady-state potassium content of the tissue is related to K(ex). by a sigmoidal cooperative curve at all temperatures. These results are compared with findings on a mammalian smooth muscle.
D000818:Animals; D001001:Anura; D066298:In Vitro Techniques; D007700:Kinetics; D008962:Models, Theoretical; D009132:Muscles / Q000032:analysis / Q000378:metabolism*; D010783:Photometry; D011188:Potassium / Q000032:analysis / Q000378:metabolism*; D012964:Sodium / Q000032:analysis / Q000378:metabolism*; D013696:Temperature
D012964:Sodium; D011188:Potassium