| Abstract: | ![]()
Experiments were performed to explore the influence of (PGE1) prostagandin E1 on the local regulation of blood flow in the terminal vascular bed of the rat mesoappendix. The vasomotor activity of PGE1 on specific vascular components of the microcirculation as well as its effects on vascular responsiveness to locally applied vasoconstrictor and vasodilator agents were documented by direct in vivo microscopic observation. Locally administered PGE1 transiently dilated all muscular microvessels. Unlike the other naturally occurring vasodilator agents such as bradykinin and histamine, PGE1 antagonized the constrictor action of angiotensin, epinephrine, norepinephrine, and vasopressin long after its vasodilator activity had vanished. However, PGE1 did not interfere with the constrictor activity of serotonin, nor did it alter vascular responsiveness to the dilators, bradykinin, and histamine. Findings suggest that PGE1 may serve as a local hormonal regulator of blood flow in the microcirculation by virtue of its vasodilator properties and its ability to suppress vascular responsiveness to endogenous constrictor amines and polypeptides. |
