title: [Origin and fixation of pyrophosphates in the parietal bones of young rats].
abstract: Calvaria from 6 to 13-day-old rats mineralize and bind pyrophosphates which are transferred from nucleotides, as shown by : 1 -- the increase of pyrophosphates in young rat calvaria incubated with nucleoside triphosphate, especially ATP ; 2 -- the more important increase of pyrophosphate content when ATP is renewed in the incubation medium ; and 3 -- binding of [32P] pyrophosphate [beta 32P] ATP. The effect of preheating of calvaria on 32P binding from [beta32P]ATP led us to assume that two systems might be involved in pyrophosphate fixation : a heat-labile, non-specific, phosphatase system, and a heat-stable pyrophosphotransferase system. cAMP increases the pyrophosphate content of calvaria incubated with ATP : that effect may result from either an inhibition of the phosphatase system, or an activation of the pyrophosphotransferase system.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000375:Aging; D000818:Animals; D001846:Bone Development; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D000242:Cyclic AMP / Q000494:pharmacology; D011756:Diphosphates / Q000378:metabolism*; D007700:Kinetics; D051381:Rats
chemical_list: D011756:Diphosphates; D000255:Adenosine Triphosphate; D000242:Cyclic AMP
vernacular_title: Origine et fixation des pyrophosphates des pariétaux de jeunes rats.