AJP - Renal Physiology, Vol 249, Issue 1 139-F147, Copyright © 1985 by American Physiological Society
Effects of vasopressin on phosphoinositides and prostaglandin production in cultured mesangial cells
D. A. Troyer, J. I. Kreisberg, D. W. Schwertz and M. A. Venkatachalam
We studied the effects of vasopressin on phospholipid metabolism in
mesangial cells and the temporal relationship of these changes to
prostaglandin production. The changes included: 1) increased breakdown of
phosphatidylinositol (PI), 2) increased breakdown of diphosphoinositide
(PI-P) and triphosphoinositide (PI-P2), 3) an increase in the mass of
diglyceride and phosphatidic acid, 4) increased synthesis, first of PI-P
and PI-P2, then phosphatidic acid, and, finally, PI, and 5) increased
water-soluble inositol phosphates. Vasopressin treatment resulted in a
significant increase (90%) in the mass of phosphatidic acid and a smaller
(13%) decline in the mass of PI. Changes in diglyceride were seen following
45 s of treatment with vasopressin. Alterations of phosphoinositide
metabolism were seen as early as 45 s and continued for up to 5 h following
hormone exposure. By contrast, prostaglandin production declined after 30
min. These observations on vasopressin-stimulated metabolism in cultured
mesangial cells may provide a basis for an understanding of the functional
changes that follow hormone exposure.
