Renal-clip hypertension in rabbits immunised against angiotensin II.

The rabbit immunized against angiotensin II was shown to be a valid model for the study of renal-clip hypertension. In particular, there was a specific and complete blockade of the pressor effect of high doses of intravenous renin and angiotensin in vivo, even at angiotensin II production rates which far exceeded those associated with renal-clip hypertension. Despite this, four immunized rabbits developed hypertension after renal-artery clipping with contralateral nephrectomy, and in three of these the hypertension was severe. In four other rabbits, there was no evidence of modification of an established hypertension after immunization against angiotensin II. In both groups, the specific absence of pressor response to high doses of renin and angiotensin II after immunization was confirmed. These studies provide strong evidence that angiotensin is not the sole or even the major factor in either the initiation or maintenance of this form of hypertension. ADDITIONAL