Transforming growth factor-beta is a renin secretagogue at picomolar concentrations

Transforming growth factor-beta s (TGF-beta s), a family of peptides, have many actions including modulating cellular growth, differentiation, and influencing steroidogenesis. Because both TGF-beta and renin are present in renal juxtaglomerular cells, we have examined the effects of these peptides on renin secretion using static incubations of rat renal cortical slices. We report here an effect of both TGF-beta 1 and -beta 2 on renin secretion. At low concentrations, both TGF-beta 1 (4 x 10(-12) M) and -beta 2 (8 x 10(-12) M) stimulate basal renin secretion (control, 100 +/- 4%; TGF-beta 1, 123 +/- 4%; TGF-beta 2, 124 +/- 5%; both P < 0.02 compared with control). However, at higher concentrations (2 x 10(-10) M), both peptides do not alter basal renin release. Our previous studies show that both prostaglandins and lipoxygenase (LO) products of arachidonic acid play an important dual regulatory role in renin secretion; therefore, we have examined the effects of both cyclooxygenase (CO) and LO inhibition in TGF-beta action.(ABSTRACT TRUNCATED AT 250 WORDS)