cAMP levels from endogenous and exogenous arachidonic acid in isolated dog lung.
We infused exogenous arachidonic acid (AA) into salt-perfused isolated dog lungs. This led to elevations in adenosine 3',5'-cyclic monophosphate (cAMP) which were from conversion of the AA to cyclooxygenase products. The maximal levels of cAMP occurred at far less than maximal levels of cyclooxygenase products. Next, we infused A 23187 to release endogenous pulmonary AA. This led to elevations in cAMP that were from conversion of this endogenous AA to cyclooxygenase products. The level of these products was far less than maximal levels from exogenous AA. However, maximal levels of cAMP from conversion of endogenous AA were similar to maximal levels of cAMP from conversion of exogenous AA. We conclude that maximal levels of pulmonary cAMP from endogenous or exogenous AA are from conversion of the AA to far less than maximal levels of pulmonary cyclooxygenase products. This indicates that levels of cAMP rather than levels of cyclooxygenase products are a potential rate-limiting step in cAMP-linked pulmonary actions of such products from pulmonary conversion of endogenous or exogenous AA.
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D000001:Calcimycin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism*; D004285:Dogs; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008168:Lung / Q000187:drug effects / Q000378:metabolism*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D011453:Prostaglandins / Q000378:metabolism*; D013929:Thromboxane B2 / Q000378:metabolism
D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D011453:Prostaglandins; D016718:Arachidonic Acid; D000001:Calcimycin; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D013929:Thromboxane B2; D000242:Cyclic AMP; D011451:Prostaglandin-Endoperoxide Synthases