Effects of beta-adrenergic blockade on the glomerular and tubular response to acute renal denervation.
Using micropuncture techniques in euvolemic adult male Munich-Wistar rats, we assessed the functional role of renal beta-adrenoceptors in mediating neural control of glomerular filtration and proximal tubular reabsorption. The determinants of nephron filtration and rate of proximal tubular reabsorption were measured in two groups of animals before and after acute surgical renal denervation (DNX). Group A animals (n = 6) were pretreated with the beta-adrenoceptor antagonist propranolol (25 mg/kg body weight per day for 4-6 days). Group B animals (n = 7) served as non-beta-blocked controls. Acute renal DNX resulted in no significant change in nephron filtration rate or any of its determinants in either group. Acute DNX caused similar decrements in the rate of fluid reabsorption from the proximal convoluted tubule of beta-blocked and control rats. Loop of Henle fluid reabsorption did not appear to be affected by DNX in either group. Because the effect of denervation on proximal tubular reabsorption was not conditioned by prior beta-blockade, the beta-adrenoceptors present within the proximal convoluted tubule do not appear to be the primary mediators of the adrenergic influence on fluid transport in that segment of the nephron.
Thomson
S C
SC
Department of Medicine, University of California, School of Medicine, San Diego.
Tucker
B J
BJ
Blantz
R C
RC
D000042:Absorption; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D001834:Body Water / Q000378:metabolism; D003714:Denervation; D006439:Hemodynamics / Q000187:drug effects; D007668:Kidney / Q000294:innervation*; D007678:Kidney Glomerulus / Q000294:innervation / Q000502:physiology*; D007684:Kidney Tubules / Q000294:innervation / Q000502:physiology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*
D000319:Adrenergic beta-Antagonists; D011943:Receptors, Adrenergic, beta