ACUTE EFFECTS OF CALCITONIN-GENE-RELATED PEPTIDE ON RENAL HEMODYNAMICS AND RENIN AND ANGIOTENSIN-II SECRETION IN PATIENTS WITH RENAL-DISEASE

The renal haemodynamic effects and renin-angiotensin II response io ca lcitonin gene-related peptide (CGRP) infusion were assessed in 16 pati ents with moderate hypertension and renal insufficiency. CGRP lowered the systemic mean blood pressure by 13% and increased the heart rate b y 25%; the glomerular filtration rate rose from 56 +/- 11 ml/min to 71 +/- 8 ml/min (p < 0.005), the renal plasma flow decreased from 369 +/ - 19 ml/min to 342 +/- 25 ml/min (p < 0.002) and the filtration fracti on increased from 15 +/- 0.2% to 20 +/- 0.2%. Plasma renin activity ro se stepwise during the CGRP infusion from 1.28 +/- 0.5 ng/ml/h to 1.66 +/- 0.4 and 1.89 +/- 0.4 ng/ml/h (p < 0.001). Angiotensin II showed a marked increase after 10 min of infusion (91.6 +/- 47.00 pg/ml) (cont rol value 6.01 +/- 3.09 pg/ml) and at the end (28.63 +/- 16.00 pg/ml) (p < 0.001). CGRP exerts an apparently favourable effect on renal func tion of patients with renal insufficiency, but the observed increase o f glomerular filtration rate is obtained by an increase of intraglomer ular pressure secondary to angiotensin II production.