TY - JOUR
T1 - Renal responses to hypertonic saline infusion in salt-sensitive spontaneously hypertensive rats
AU - Mozaffari, Mahmood S.
AU - Roysommuti, Sanya
AU - Shao, Zuohai H.
AU - Michael Wyss, J.
N1 - Funding Information:
From the * Department orOral Biology / Pharmacology, School of Dentistry, Medical College of Georgia, Augusta, and the t Department of Cell Biology, University of Alabama, Birmingham. This study was supported in part by a grant from the American Heart Association, Alabama Affiliate (MSM) and a grant from the National Institute of Health HL37722 (JMW). Correspondence: Mahmood S. Mozaf{ari, PhD, DMD, Department of Oral Biology / Pharmacology, School of Dentistry, Medical College of Georgia, Augusta, GA 30912-1128.
PY - 1997/12
Y1 - 1997/12
N2 - In Wistar Kyoto (WKY) and Sprague Dawley rats, high dietary sodium chloride (NaCl) increases natriuretic and diuretic responses to acute isotonic saline infusion, but in NaCl-sensitive spontaneously hypertensive rats (SHR-S), a high-NaCl diet causes negligible increases in natriuretic and diuretic responses. To investigate whether this deficit in sodium and fluid excretion in SHR-S is stimulus (volume)-specific or because of a more generalized alteration in renal function, the present study measured, in SHR- S and Wistar Kyoto rats, natriuretic and diuretic responses to a hypertonic saline infusion (the Amount of sodium infused was equal to that infused in a previous, isotonic experiment). Eight-week-old Wistar Kyoto rats, SHR-S, and salt-resistant SHR were given a basal (1%) or high (8%)-NaCl diet for 2 weeks. Intravenous infusion of hypertonic saline increased mean arterial pressure and reduced heart rate in all groups. Baseline sodium excretion was lower in SHR-S compared with salt-resistant SHR with either diet, but after infusion of hypertonic saline, all 6 groups displayed significant increases in sodium and fluid excretion, glomerular filtration rate, and effective renal blood flow (ERBF). The percent-sodium excretion in response to hypertonic saline infusion was slightly, but significantly, lower in SHR-S (compared with salt-resistant SHR) for either the basal or the high-NaCl diet. We conclude that renal responses to hypertonic saline infusion are affected minimally in SHR-S compared with salt-resistant SHR or Wistar Kyoto rats. Therefore, the deficits in renal function observed in SHR-S after volume loading are not reflected in a renal deficit to hypertonic saline challenge.
AB - In Wistar Kyoto (WKY) and Sprague Dawley rats, high dietary sodium chloride (NaCl) increases natriuretic and diuretic responses to acute isotonic saline infusion, but in NaCl-sensitive spontaneously hypertensive rats (SHR-S), a high-NaCl diet causes negligible increases in natriuretic and diuretic responses. To investigate whether this deficit in sodium and fluid excretion in SHR-S is stimulus (volume)-specific or because of a more generalized alteration in renal function, the present study measured, in SHR- S and Wistar Kyoto rats, natriuretic and diuretic responses to a hypertonic saline infusion (the Amount of sodium infused was equal to that infused in a previous, isotonic experiment). Eight-week-old Wistar Kyoto rats, SHR-S, and salt-resistant SHR were given a basal (1%) or high (8%)-NaCl diet for 2 weeks. Intravenous infusion of hypertonic saline increased mean arterial pressure and reduced heart rate in all groups. Baseline sodium excretion was lower in SHR-S compared with salt-resistant SHR with either diet, but after infusion of hypertonic saline, all 6 groups displayed significant increases in sodium and fluid excretion, glomerular filtration rate, and effective renal blood flow (ERBF). The percent-sodium excretion in response to hypertonic saline infusion was slightly, but significantly, lower in SHR-S (compared with salt-resistant SHR) for either the basal or the high-NaCl diet. We conclude that renal responses to hypertonic saline infusion are affected minimally in SHR-S compared with salt-resistant SHR or Wistar Kyoto rats. Therefore, the deficits in renal function observed in SHR-S after volume loading are not reflected in a renal deficit to hypertonic saline challenge.
KW - High salt
KW - Hypertensive rat
KW - Hypertonic saline
KW - Natriuretic
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U2 - 10.1097/00000441-199712000-00003
DO - 10.1097/00000441-199712000-00003
M3 - Article
C2 - 9413341
AN - SCOPUS:0031467897
SN - 0002-9629
VL - 314
SP - 370
EP - 376
JO - American Journal of the Medical Sciences
JF - American Journal of the Medical Sciences
IS - 6
ER -