Effects of Ph CL 28A on eicosanoid synthesis in rat isolated hearts.
The effects of Ph CL 28A, a derivative of sulphasalazine, on cardiac function and eicosanoid synthesis were examined in rat isolated hearts perfused via the coronary circulation. Two stimuli for eicosanoid synthesis were used: exogenous arachidonic acid (AA) or the calcium ionophore, A23187. Following exogenous AA, coronary perfusion pressure (CPP) and cardiac developed tension (CDT) increased transiently; only the CPP response was diminished by Ph CL 28A. The output of TxB2 but not that of 6-oxo-PGF1 alpha from the heart after exogenous AA was inhibited by Ph CL 28A. The ionophore, A23187, increased CPP with minor changes in CDT; Ph CL 28A did not affect either response. The ionophore released 6-oxo-PGF1 alpha, TxB2 and LTC4 from the heart but only LTC4 output was decreased by Ph CL 28A. We conclude that, although Ph CL 28A did not increase output of 6-oxo-PGF1 alpha from rat heart with either of the stimuli used, its inhibition of the output of vasoconstrictor eicosanoids could be of benefit to the coronary circulation.
Nakamura
M
M
Department of Pharmacology, Hunterian Institute, Royal College of Surgeons, Lincoln's Inn Fields, London, England.
Bakhle
Y S
YS
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D001391:Azo Compounds / Q000494:pharmacology*; D000001:Calcimycin / Q000494:pharmacology; D003326:Coronary Circulation / Q000187:drug effects; D005069:Evaluation Studies as Topic; D006321:Heart / Q000187:drug effects*; D015289:Leukotrienes / Q000378:metabolism*; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000378:metabolism; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D014662:Vasoconstrictor Agents / Q000378:metabolism
D001391:Azo Compounds; D015289:Leukotrienes; D014662:Vasoconstrictor Agents; D016718:Arachidonic Acid; D000001:Calcimycin; C047498:Ph CL 28A