ANGIOTENSIN-DEPENDENT GENE-EXPRESSION IN THE DEVELOPING RAT-KIDNEY

We aimed to identify genes involved in the growth effects of angiotens in II (Ang II) during kidney development. In rats treated from birth w ith the Ang II type-1 receptor blocker losartan, expression of transfo rming growth factor beta 1 (TGF-beta 1), platelet-derived growth facto r B (PDGF-B), vascular endothelial growth factor (VEGF). and epidermal growth factor (EGF). as measured by Northern blot, did not change sig nificantly (N = 4 to 6 per group each). Differential display methods, used to identify genes with Ang II-dependent expression, produced most ly false positives. We identified one novel rat partial cDNA, termed A D.5, that is related to a human orphan receptor. AD.5 was expressed in a developmentally regulated pattern and may be involved in kidney dev elopment and/or the trophic actions of Ang II.