title: Adenine nucleotide levels and adenosine metabolism in cultured calvarial bone.
abstract: Adenine nucleotide levels were measured in extracts of murine calvaria after different periods of culture with or without parathyroid hormone (PTH; 10(-8) M) or PGE2 (10(-7) M). In control calvaria the energy charge, (ATP + 1/2 ADP)/(ATP + ADP + AMP), remained at close to 0.7 over a 24 hour culture period. However, bones cultured with PTH or PGE2 showed a transient fall in the energy charge down to 0.5. This was not associated with a fall in total adenine nucleotides. The rate of adenosine metabolism in cultured bone in vitro was studied by determining the contents of adenosine, inosine, 2-deoxyadenosine, 2-deoxyinosine and hypoxanthine in the culture medium. There was a continuous increase in adenosine, inosine and hypoxanthine as well as a disappearance of medium 2-deoxyadenosine that was accounted for by appearance of 2-deoxyinosine. The deaminating activity could only partly be accounted for by activity in the medium and thus probably mainly resides in the bone cells. PTH (10(-8) M) did not alter the rate of disappearance of 2-deoxyadenosine or adenosine deaminase activity determined in bone extracts. The results demonstrate that two substances that increase calcium mobilization from bone alter ATP utilization and/or synthesis without significantly influencing adenosine production or metabolism.
mesh_terms: D000227:Adenine Nucleotides / Q000378:metabolism*; D000241:Adenosine / Q000378:metabolism*; D000243:Adenosine Deaminase / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000378:metabolism; D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001842:Bone and Bones / Q000378:metabolism*; D002478:Cells, Cultured; D003839:Deoxyadenosines / Q000378:metabolism; D015232:Dinoprostone; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000378:metabolism; D007288:Inosine / Q000031:analogs & derivatives / Q000378:metabolism; D007291:Inosine Monophosphate / Q000378:metabolism; D051379:Mice; D010281:Parathyroid Hormone / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D014527:Uric Acid / Q000378:metabolism
chemical_list: D000227:Adenine Nucleotides; D003839:Deoxyadenosines; D007042:Hypoxanthines; D010281:Parathyroid Hormone; D011458:Prostaglandins E; D007291:Inosine Monophosphate; D014527:Uric Acid; D019271:Hypoxanthine; D000249:Adenosine Monophosphate; D007288:Inosine; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D000243:Adenosine Deaminase; C012271:deoxyinosine; D000241:Adenosine; D015232:Dinoprostone