Renal vascular response to amino acids: effect of pancreatectomy.
We ascertained the importance of glucagon in modulating the renal hemodynamic response to amino acid (AA) infusion in anesthetized dogs. In controls (n = 6), AAs (L-serine, alanine, and proline; 0.051 mmol.kg-1.min-1 iv) elevated renal blood flow (RBF) and glomerular filtration rate (GFR) by 35 and 34%, respectively, while elevating arterial plasma glucagon-like immunoreactivity (AGLI) by 96 pmol/l. In control pancreatectomized (PX) dogs (n = 6), all parameters remained at control values over 2 h. In PX dogs, AAs (n = 6) failed to reproduce the renal hemodynamic and AGLI responses elicited by AAs in controls. In PX dogs infused with AAs, replacement of AGLI (n = 6) to an incremental plasma level of 111 pmol/l, a level no different than that produced by AAs in controls, elevated RBF and GFR by 25 and 26.5%, respectively. These hemodynamic responses were 71 and 78%, respectively, of the total responses elicited by AAs in controls. In PX dogs infused with glucagon alone (0.86 pmol.kg-1.min-1; n = 6), an incremental change in AGLI of 112 pmol/l was accompanied by only small increases in RBF and GFR (9%). These data suggest the importance of glucagon in modulating the renal hyperemia and hyperfiltration ascribed to AA infusion in anesthetized dogs.
Premen
A J
AJ
Department of Physiology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814-4799.
Powell
D A
DA
Carroll
R G
RG
Dobbins
D E
DE
D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D004285:Dogs; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D005934:Glucagon / Q000097:blood / Q000494:pharmacology; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D010180:Pancreatectomy; D012079:Renal Circulation / Q000187:drug effects*; D013997:Time Factors
D000596:Amino Acids; D005934:Glucagon