Release Of Prostaglandin-like Substance Research Articles

Enhanced thromboxane A 2 biosynthesis in the kidney of spontaneously hypertensive rats during development of hypertension

Arachidonic acid (AA)-induced pressor response and production of thromboxane YXB 2, the stable metabolite of TXA 2, prostaglandin (PG)-like substance (PLS) and 6-keto-PGF 1α the stable metabolite of prostacyclin (PGI 2), were studied using isolated, perfused kidneys of 6- and 18-week old spontaneously hypertensive rats (SHR), Wistar-Kyoto rats (WKY), two-kidney, one clip hpertensive rats (RHR) and DOCA/salt hypertensive rats (DOCA/salt HR). The AA-induced pressor response and release of TXB 2 were highest in the 6-week old SHR, whereas, the release of PLS and 6-keto-PGF 1α was marked in the 18-week old SHR and the established hypertensive stages of both RHR and DOCA/salt HR. In the kidneys of SHR and WKY, exogenous TXA 2 induced a severe vasoconstriction and there was a positive correlation between the AA-induced pressor response and the release of TXB 2 or PLS. Thus, the initiation of hypertension in SHR may follow an accelerated synthesis of TXA 2 against PGI 2 in response to stimuli which induce a release of AA.

Release of prostaglandin-like substance from inflamed synovial tissue of rat

Influence of inflammation on the release of prostaglandin-like substance (PG) from synovial tissue of rat was studied. 1. 1) In carrageenin inflammation, PG release was proportional to the increase in synovial tissue weight. 2. 2) PG release was only increased in the later phase of dextran inflammation. 3. 3) Aspirin suppressed PG release from both non-inflamed and inflamed synovial tissues, but hydrocortisone suppressed that only in inflamed tissue.

Effects of Estradiol and Oxytocin on the Release of Prostaglandin-Like Substance from Isolated Rat Uterus

Effects of estradiol on the release of prostaglandin-like substance (PG) from rat uterus was investigated. The amount of PG released into a medium that did not contain oxytocin was decreased by estradiol, but the release of PG was remarkably increased by the addition of oxytocin. No significant correlation was found in the relationship between PG release and uterine contraction in uterus of either the ovariectomized rat and that of the estradiol-injected rat. The amount of PG released from the uterus of ovariectomized rat and the uterus of 6 hours after estradiol injection was decreased by indomethacin. The PG release promoting action of oxytocin observed in estradiol-injected rat uterus disappeared completely with treatment of phospholipase C.

Prostaglandin release by the isolated perfused rabbit heart

The adenine nucleotides, ATP and ADP, were the only consistent releasers of prostaglandin-like substance (PLS) from the isolated perfused rabbit heart. Indomethacin abolished the release of PLS induced by ATP and ADP. Norepinephrine, bradykinin, and angiotensin I and II were ineffective as PLS releasers.