Fig 1.

 Expression of AT₁ angiotensin II receptor in cortex and medulla from NP, LP, and RP fed rats. RT-PCR for AT₁ receptor cDNA (385-bp product) was performed on RNA isolated from cortex and medulla of kidney homogenates. Representative gels of AT₁ mRNA in cortex and medulla from controls (NP), LP, and RP after readministration of 24% protein for 14, 21, and 30 days are shown. Amplification of corresponding β-actin mRNA is shown. These results are typical of 5 independent observations. Semiquantitative PCR analysis of AT₁ angiotensin II receptor. Top, Densitometric analysis of AT₁ angiotensin II receptor and β-actin showed increased AT₁ receptor/β-actin mRNA ratio in LP cortex related to NP cortex kidneys (**P < 0.01). Increased AT₁ receptor/β-actin mRNA ratio incortex from RP after 14 days was shown, related to NP 14 days, (*P < 0.05). Bottom, Densitometric analysis. LP medulla related to NP medulla kidneys (*P < 0.05). Persistent increased AT₁ receptor/β-actin mRNA ratio in medulla from RP after 14 days was shown, related to NP 14 days, (*P < 0.05). Values are means ± SEM