Calcitonin gene-related peptide attenuates experimental ischemic renal failure in a rat model of reversible renal ischemic insult.

Calcitonin gene-related peptide (CGRP) has been shown to decrease vascular resistance and increase renal blood flow. To study the effects of CGRP in acute renal failure (ARF) of moderate degree, we used a rat model of bilateral temporary renal artery occlusion (RAO) inducing ARF with spontaneous recovery within 1 week, resembling a clinical situation. Three groups were studied: CGRP 10 (CGRP10) and 25 (CGRP25) pmol.kg-1.min-1 and vehicle alone (control), respectively, infused from 10 min before until 2 h after declamping. Serum urea levels reached a peak after 24 h at 13.0 +/- 1.3, 8.1 +/- 1.1, and 8.5 +/- 1.0 mmol.L-1 in the control, CGRP10, and CGRP25 group, respectively. They were significantly lower postischemia in the two CGRP-treated groups than in the control group. Mean arterial pressure (MAP) decreased to 90%, 80%, and 60% of baseline MAP in the control, CGRP10, and CGRP25 group, respectively. Histologically there was no significant difference between the three groups. Our data indicate that CGRP preserves renal function in experimental ARF despite reductions in MAP. We conclude that further investigations of the renal effects of CGRP are needed in order to clarify whether CGRP might be used clinically to maintain or improve renal function in ARF.