Prostaglandin synthesis by rat glomerular mesangial cells in culture. Effects of angiotensin II and arginine vasopressin.

Abstract

A B S T R A C T Arginine vasopressin (AVP) and angiotensin II (ANG II) reduce the glomerular filtration rate and ultrafiltration coefficient. Vasodilatory prostaglandins (PG) antagonize these effects. AVP and ANG II also cause mesangial cell contraction. Therefore, possible PG stimulation by these peptides and two vasopressin analogues was studied in cultured rat glomerular mesangial cells. The effect of altered calcium availability on PG production was also studied.Glomeruli from 75-100-g Sprague-Dawley rats were cultured in supplemented nutrient media for 28 d and experiments were performed on the first passage. Mesangial cell morphology was confirmed by electron microscopy. Cells produced PGE2 > PGF2a > 6-ketoPGFia > thromboxane B2 when incubated with the divalent cation ionophore, A23187, or arachidonic acid (C20:4). ANG II and AVP selectively stimulated PGE2 at threshold concentrations of 10 nM ANG II and 100 pM of AVP. The effects of the antidiuretic analogue 1-desamino-8-D-arginine vasopressin (dDAVP) and the antipressor analogue [1-(,-

Eicosanoids, Mesangial Contraction, and Intracellular Signal Transduction.

“…A possible explanation is the simultaneous release of other prostanoids with agonist activity on contraction, e.g., PGF2a and TxA2. The former particularly is a relevant product of cultured rat mesangial cells (Kreisberg et al 1982;Scharschmidt and Dunn 1983).…”

“…Alternative sources of increased TxA2 are glomerular epithelial and mesangial cells, also capable of metabolizing AA to TxA2, although the synthesis of other prostaglandins (PG), such as PGE2 and PGE2a predominates (Kreisberg et al 1982;Scharschmidt and Dunn 1983). Lipooxygenase metabolites of AA also have potent effects on vascular smooth muscle and chemotactic properties on leukocytes (Hammarstrom 1983;Lewis and Austen 1984).…”

Cross‐talk between transmembrane signalling systems: a prerequisite for the delicate regulation of glomerular haemodynamics by mesangial cells

“…An increase in intracellular free calcium with the calcium ionophore A23 187 or a direct activation of phospholipase A2 with melittin strongly enhances the basal formation of prostaglandins by mesangial cells [46,103]. Many calcium-mobilizing hormones stimulate the formation of prostaglandins as summarized in Table 1.…”

Cyclic GMP accumulation by atriopeptins in cultured rat renal and vascular smooth muscle cells.

“…VSM cells at pasgage levels 3-9 and primary RPCT cells on days 4 or 5 of culture were used for experiments. GM cells were isolated simultaneously with RPCT cells from renal cortex of Sprague-Dawley rats according to the methods as previously described (Scharschmidt and Dunn 1983 ;Sato and Dunn 1984) with some modifications. After the glomeruli were prepared using 106-and 75-,uM sieves, they were placed in Hank's Balance Salt Solution without calcium and magnesium containing 750 U/ml collagenase (Type IV) with the antibiotic-antimycotic (1:100).…”