Calcitonin increases calcium content and glucose-6-phosphatase activity in hepatic microsomes of rats.
The effect of calcitonin (CT) on calcium content and glucose-6-phosphatase activity in the hepatic microsomes of rats was investigated. A single sc administration of CT (80 MRC mU/100 g body weight) produced a significant increase in microsomal calcium content and a corresponding elevation of microsomal glucose-6-phosphatase activity. An appreciable effect of CT was observed at a dose of 20 MRC mU/100 g body weight. On the other hand, the removal of calcium by 10 mM EGTA washing of the microsomes caused a marked reduction of glucose-6-phosphatase activity raised by CT administration. The addition of calcium ion at the amount of 10(-2)-10(3) nmoles Ca2+ per mg protein in the microsomes produced a significant increase in glucose-6-phosphatase activity. The present results suggest that microsomal calcium increased by CT administration activates glucose-6-phosphatase in the hepatic microsomes of rats.
D000818:Animals; D002116:Calcitonin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000494:pharmacology; D005952:Glucose-6-Phosphatase / Q000378:metabolism*; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D004533:Egtazic Acid; D002116:Calcitonin; D005952:Glucose-6-Phosphatase; D002118:Calcium