Effects of Prostaglandin on Cutaneous Arteries and Veins in Vivo in the Isolated Rabbit Ear.

摘要

The dose dependent effects of i.a. PGF(2 alpha) and PGE(2) on cutaneous arteries and veins were studied at constant blood flow. Norepinephrine served as the standard vasoconstrictive agent. Changes in arteriolar resistance, venous diameter, and venous pressure gradient were measured. PGF(2 alpha) caused vasoconstriction of arterial and venous vessels. The doses of PGF(2 alpha) required to produce a given response in veins were ten times greater than the dose of norepinephrine needed to obtain the same response. On the arterial side, this relationship was 30:1. The constrictive effects of PGF(2 alpha) were completely eliminated by infusion of papaverine. Spontaneous rhythmic contractions of the venous vessels down to a size of 50 micrometers were observed consistently in these experiments. The frequency increased significantly with increasing PGF(2 alpha) concentration. The effects of PGE(2) were studied during norepinephrine constriction. PGE(2) abolished the effects of norepinephrine completely on the venous side and incompletely on the arterial side. (Author)