Different Responses to Prostaglandins E1 and E2 of Isolated Canine Coronary Arteries

Abstract

It has been demonstrated that prostaglandin E1 (PGE1) and E2 are structurally quite similar and share the same actions on the systemic blood pressure (1, 2), the isolated vascular smooth muscle (3) and the sympathetic neurotransmission (4). In contrast, the present study describes the different effects of PGE1 and E2 on isolated canine coronary arteries.Mongrel dogs were anesthetized with sodium pentobarbital and sacrificed by bleeding from carotid arteries. The interventricular branch of left coronary arteries of 0.5 to 0.8 mm outside diameter was isolated and helically cut into strips. The specimen was fixed under a resting tension of 1.5 g in a muscle bath containing the nutrient solution maintained at 37'C. Isometric contractions and relaxations were recorded. Details of the experimental procedures are described in an earlier report (5). Paired comparison of the effect of PGE1and E2 in 9 preparations from 9 dogs was made.

Prostacyclin: A Potentially Valuable Agent for Preserving Myocardial Tissue in Acute Myocardial Ischemia

“…The overall chamber thickness is 1.1 mm and the tissue is within 75 ,Am of the inner surface of the bottom cover glass. The chamber was modified from a Dvorak-Stotler tissue culture chamber (7). The tissue is held mucosal side downward between concentric rings that are placed inside a plastic spacer.…”