Effects of XXXX on isolated @entity35 glomeruli and cultured mesangial cells.

@entity1831 @entity1439 @entity4443 @entity5463 @entity1421 @entity1808 @entity3009 @entity1346 @entity35
Several vasoactive substances influence glomerular function in vivo and alter glomerular surface area and @entity3009 (PG) synthesis in vitro. @entity4443 (LT) LTC4 and LTD4 may also influence glomerular function in vivo and in the isolated perfused kidney. We therefore compared the effects of LT with those of @entity1808 ( @entity1808 ), @entity5463 ( @entity1831 ), and platelet activating factor (PAF) on planar surface area of isolated @entity35 glomeruli and the shape change of cultured mesangial cells and their PG synthesis. @entity1808 , AVP, and PAF decreased the surface area of isolated @entity35 glomeruli by 10-14% with comparable changes induced by LTC4 and LTD4. Half-maximal effects of LTs were observed at approximately 10(-7) M. Incubation of cultured @entity35 mesangial cells with LTC4 or LTD4 at 10(-7) and 10(-8) M was also associated with shape changes of the cells resulting in significant reductions in planar surface area in a dose- and time-dependent fashion similar to that noted previously with other vasoactive agents. In cells grown on a flexible @entity1346 rubber support, LTD4 resulted in rapid increases in wrinkling of the mobile surface indicating that the shape change may represent cell contraction. The LT-mediated decrease in surface area of glomeruli and mesangial cells was partially antagonized by the LT inhibitor @entity1439 . In contrast to the 11- and 7-fold enhancement of @entity1421 synthesis in cultured mesangial cells by @entity1808 or PAF, neither LTC4 nor LTD4 affected @entity1421 production. These results demonstrate that LTC4 and LTD4 cause mesangial shape changes that in the whole glomerulus may decrease glomerular surface area.(ABSTRACT TRUNCATED AT 250 WORDS)
