Divergent roles of angiotensin II upon the immediate and sustained increases of renal blood flow following unilateral nephrectomy

Am J Physiol Renal Physiol. 2022 Feb 28. doi: 10.1152/ajprenal.00376.2021. Online ahead of print.ABSTRACTAlthough the molecular and functional responses related to the renal compensatory hypertrophy after unilateral nephrectomy (UNX) has been well described, many aspects of these events remain unclear. One question is how the remaining kidney senses the absence of the contralateral organ and another what the role of the renin-angiotensin system is in these responses. Both acute anesthetized and chronic unanesthetized studies were performed using the AT1-receptor blocker losartan and the renin inhibitor aliskiren to determine the contribution of the renin-angiotensin system to the immediate and losartan for the chronic changes of RBF and the associated hypertrophic events in male Sprague-Dawley rat. Chronic studies utilized implanted RBF probes and arterial catheters for continuous data collection and GFR determined by non-invasive transcutaneous FITC-sinistrin measurement. The results of the acute studies found that RBF increased nearly 25% (4.6 ± 0.5 to 5.6 ± 0.6 ml/min/gkw)) during the first 15 minutes following UNX and this response was abolished by losartan (6.7 ± 0.7 to 7.0 ± 0.7 ml/min/gkw) or aliskiren (5.8 ± 0.4 to 6.0 ± 0.4 ml/min/gkw) treatment. Thereafter, RBF increased progressively over 7 days and kidney weight increased by 19% of pre-UNX values. When normalized to kidney weight determined at day 7 post-UNX the RBF was not significantly different from pre-U...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Source Type: research