Studies on adenylate cyclase-cyclic AMP system of the myopathic hamster (UM-X7.1) skeletal and cardiac muscles.
Cyclic AMP content, adenylate cyclase (EC 4.6.1.1) activity and phosphodiesterase I (EC 3.1.4.1) activity of the hind leg skeletal muscle and cardiac muscle in 60- and 150-day-old normal and myopathic (UM-X7.1) hamsters were examined. In 60-day-old myopathic animals, cardiac cyclic AMP levels were higher and phosphodiesterase I activity was lower, without any changes in the basal adenylate cyclase activity, whereas in 150-day-old myopathic hamsters, cardiac cyclic AMP and basal adenylate cyclase activity were lower, without any changes in the homogenate phosphodiesterase I activity. On the other hand, basal adenylate cyclase and phosphodiesterase I activities in the skeletal muscle homogenate from 60- and 150-day-old myopathic animals were not different from the normal values but the skeletal muscle cyclic AMP levels were significantly less in 60-day-old myopathic hamsters only. The plasma cyclic AMP levels in 60-day-old myopathic hamsters, unlike 150-day-old myopathic animals, were higher than the normal. Although these results reveal differences in myopathic cardiac and skeletal muscles, it is concluded that changes in adenylate cyclase-cyclic AMP system in myopathy are dependent upon the degree of disease.
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000375:Aging; D000818:Animals; D006224:Cricetinae; D000242:Cyclic AMP / Q000378:metabolism*; D005459:Fluorides / Q000494:pharmacology; D009132:Muscles / Q000378:metabolism*; D009135:Muscular Diseases / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism
D000242:Cyclic AMP; D010727:Phosphoric Diester Hydrolases; D000262:Adenylyl Cyclases; D005459:Fluorides