[Effect of corticotropin and hydrocortisone on the Ca2+-ATPase activity of skeletal muscle sarcoplasmic reticulum].
The effect of corticotropin (ACTH1-39), synacthen (ACTH1-24) and hydrocortisone-hemisuccinate on the activity of Ca-ATPase of skeletal muscle sarcoplasmic reticulum (SR) and calcium (Ca) accumulation in SR vesicles has been studied. It has been shown that ACTH1-39 (I U per 100 g body weight) increased the activity of Ca-ATPase in skeletal muscle SR of rats, while hydrocortisone (5 mg per 100 g body weight) did not change the activity of Ca-ATPase in skeletal muscle SR. However, both hormones increase the total activity of ATPase. ACTH1-39 and ACTH1-24 (0.05-0.0005 U/ml) and hydrocortisone (2.8 X 10(-7)-2.8 X 10(-9) mol/l) increased in vitro Ca-ATPase isolated from rabbit skeletal muscle SR and accumulation of Ca is SR vesicles. At the same time, hydrocortisone reduced calcium/phosphorus ratio, while ACTH1-39 and ACTH1-24 increased it, i.e. hydrocortisone facilitated Ca accumulation in SR requiring more ATP energy, whereas ACTH facilitated Ca accumulation in SR requiring less ATP energy.
D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D006854:Hydrocortisone / Q000494:pharmacology*; D008297:Male; D051381:Rats; D012519:Sarcoplasmic Reticulum / Q000187:drug effects / Q000201:enzymology*
D000324:Adrenocorticotropic Hormone; D000252:Calcium-Transporting ATPases; D006854:Hydrocortisone
Vliianie krotikotropina i gidrokortizona na aktivnost' Ca2+-ATFazy sarkoplazmaticheskogo retikukuma skeletnykh mysh.