Growth Hormone's Exacerbating Effect On Adriamycin-Induced Nephropathy In Rats And The Mechanisms

Objectives To investigate the effect of growth hormone(GH) in the kidney of rats with adriamycin-induced nephropathy(AN) and its mechanisms, and to observe the renoprotective effect of angiotensin II receptor antagonist irbesartan in GH-treated AN rats.Methods The following groups of rats were studied: normal control rats AN rats GH-treated AN rats GH-treated AN rats plus irbesartan. Urinary protein was measured at weeks 3 6 and 9.Serum creatinineN BUNN albumin cholesteroK triglyceride were observed at the end of the study. So did ACE activity and Ang II concentration of kidney. Renal pathology changes were evaluated at the same time. Immunohistochemistry was used to examined the protein expression of TGF P i -> collagen IV > fibronectin in glomeruli.Results Glomerular mesangial proliferation glomerular sclerosis urinary protein hyperlipidemia hypoalbuminemia of GH-treated AN rats were significantly severer than AN rats (p < 0.01 ) .These indices of GH-treated AN rats plus irbesartan were significantly lower than GH-treated AN rats (p < 0.01) .There was azotemia in GH-treated AN rats ,but the others did not have this phenomenon. ACE activity of kidney was significantly (p < 0.01 ) increased in GH-treated AN rats and GH-treated AN rats plus irbesartan compared with AN rats . Ang II concentration ofkidney of GH-treated AN rats was significantly higher than AN rats (p < 0.01 ) ,but it was lower than GH-treated AN rats plus irbesartan ( p < 0.05) .The protein expression of TGF- 1 collagen IV fibronectin in GH-treated AN rats was much higher than that in AN rats and GH-treated AN rats plus irbesartan (p<0.01) . Conclusions GH is able to exacerbate adriamycin-induced nephropathy in rats ,partly through activating renal tissue RAS and starting Ang II -TGF- P rECM axis, angiotensin II receptor antagonist irbesartan has some renal protective effect in AN rats treated with GH.