Prostaglandin synthesis inhibition by maternal and fetal sheep plasma and its relation to haptoglobin and albumin levels

doi:10.1016/0161-4630(81)90096-3

Prostaglandins and Medicine

Volume 6, Issue 2, February 1981, Pages 243-248

Prostaglandins and M...

https://doi.org/10.1016/0161-4630(81)90096-3 Get rights and content

Abstract

Mammalian plasmas and sera have been reported to contain endogenous inhibitors of prostaglandin synthesis (SIPS), but the identity and role of these suggested inhibitors is as yet undetermined.

Albumin and haptoglobin have been proposed as possible inhibitors, and it has been suggested that EIPS may have a part to play in the control of PG production during pregnancy and in the neonatal period.

As part of a series of studies aimed at elucidating the identity and role of EIPS, maternal and fetal blood samples were collected from chronically catheterized pregnant ewes, and plasma levels of albumin, haptoglobin and EIPS activity determined.

Pregnant ewe plasma possessed high EIPS activity and fetal lamb plasma little or no EIPS activity. Levels of albumin and/or haptoglobin did not consistently parallel that of EIPS activity. A post-operative rise (4 sheep studied) and a pre-parturition nadir (1 sheep studied) in maternal plasma EIPS activity were also noted.

The possible physiological significance of these results is discussed.

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Prostaglandin synthesis inhibition by maternal and fetal sheep plasma and its relation to haptoglobin and albumin levels

Abstract

The Lancet

Endogenous Inhibitor of Prostaglandin Synthetase

Nature

Plasma Proteins that Inhibit Prostaglandin Synthesis

Inhibition of Prostaglandin Synthesis In Vitro by Rat Serum

Administration of extra-amniotic arachidonic acid and the suppression of uterine prostaglandin synthesis during pregnancy in the rhesus monkey

Journal of Reproduction & Fertility

Human Haptoglobins: Estimation and Purification

Biochemical Journal (London)

Inhibition of Prostaglandin Synthesis $In Vitro$ by Rat Serum