Effects of dietary sodium and genetic background on angiotensinogen and Renin in mouse.
Elements of a renin-angiotensin system expressed along the entire nephron, including angiotensinogen secreted by proximal tubule and renin expressed in connecting tubule, may participate in the regulation of sodium reabsorption at multiple sites of the nephron. The response of this tubular renin-angiotensin system to stepwise changes in dietary sodium was investigated in 2 mouse strains, the sodium-sensitive inbred C57BL/6 and the sodium-resistant CD1 outbred. Plasma angiotensinogen was not affected by sodium regimen, whereas plasma renin increased 2-fold under low sodium. In both strains, the variation in urinary parameters did not parallel the changes observed in plasma. Angiotensinogen and renin excretion were significantly higher under high sodium than under low sodium. Water deprivation, by contrast, induced significant activation in the tubular expression of angiotensinogen and renin. C57BL/6 exhibited significantly higher urinary excretion of angiotensinogen than did CD1 animals under both conditions of sodium intake. The extent to which these urinary parameters reflect systemic or tubular responses to challenges of sodium homeostasis may depend on the relative contribution of sodium restriction and volume depletion.
Lantelme
Pierre
P
Department of Human Genetics, University of Utah Health Sciences Center, Salt Lake City, USA.
Rohrwasser
Andreas
A
Gociman
Barbu
B
Hillas
Elaine
E
Cheng
Tong
T
Petty
Gray
G
Thomas
Jennifer
J
Xiao
Sha
S
Ishigami
Tomoaki
T
Herrmann
Tracy
T
Terreros
Daniel A
DA
Ward
Kenneth
K
Lalouel
Jean-Marc
JM
D000450:Aldosterone / Q000097:blood / Q000652:urine; D000808:Angiotensinogen / Q000097:blood* / Q000235:genetics / Q000652:urine; D000818:Animals; D003404:Creatinine / Q000097:blood / Q000652:urine; D005786:Gene Expression Regulation / Q000187:drug effects; D007150:Immunohistochemistry; D007684:Kidney Tubules / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012083:Renin / Q000097:blood* / Q000235:genetics / Q000652:urine; D012982:Sodium, Dietary / Q000008:administration & dosage*; D013045:Species Specificity
D012333:RNA, Messenger; D012982:Sodium, Dietary; D000808:Angiotensinogen; D000450:Aldosterone; D003404:Creatinine; D012083:Renin