Alterations of Myocardial Prostaglandin Synthesis in Diabetes

Hyperglycemia Increased the Responsiveness of Isolated Rabbit’s Pulmonary Arterial Rings to Serotonin

“…This could be ex plained by the alteration of the pulmonary artery endothelium induced by diabetes which may impair the responses of endothe lium to vasoactive agents. In addition, it has been reported that in diabetes the metabolism of AA is disturbed, with a reduction in basal release of prostacyclin and increase in conver sion of AA to thromboxane Ao in rat heart [35], This observation could explain the in ability of indomethacin to produce any change in the basal tension of diabetic rings. Stated otherwise, indomethacin, by inhibiting the cyclo-oxygenase, inhibits the exaggerated thromboxane A: induced by diabetes and in turn, maintains a normal vascular basal tone.…”

“…They found that in both coronary vessels and in thrombocytes the production capacity of the AA metabolic pathway is enhanced by diabetes in a manner that parallels the degree of hyperglycemia [35],…”

“…NO is a small membrane-permeable gas that acts as a mediator of many physiological functions, including vascular relaxation via cGMP accumulation [8] [35] re ported that the capacity for enzymatic conver sion of AA is increased in the diabetic state. They found that in both coronary vessels and in thrombocytes the production capacity of the AA metabolic pathway is enhanced by diabetes in a manner that parallels the degree of hyperglycemia [35],…”