Kallikrein excretion in Dahl salt-sensitive and salt-resistant rats with native and transplanted kidneys.
Urinary kallikrein excretion is decreased in Dahl salt-sensitive (S) vs. salt-resistant (R) rats, and several lines of reasoning suggest not only that decreased kallikrein excretion is a marker for salt-sensitive hypertension but also that kallikrein might play a pathogenic role. Because previous cross-transplantation studies have demonstrated that the kidney's genotype plays a role in determining the blood pressure of the recipient in Dahl S and R rats, the present experiments were designed to determine whether both blood pressure and urinary kallikrein excretion "traveled with the kidney" in transplantation. The Rapp strains of S and R were maintained on a low- NaCl (0.13%) diet until kidney transplantation (bilaterally nephrectomized recipients), at which time the diet was switched to high NaCl (7.8%). Sixteen days later, blood pressures (tail-cuff plethysmography) of the cross-transplant groups (R/S and S/R, indicating kidney genotype/recipient genotype) were nearly identical to each other and intermediate between the blood pressures of the control groups with transplanted kidneys (R/R and S/S). Renal function studies, performed on anesthetized rats 17 days after surgery, demonstrated that R kidneys had higher glomerular filtration rates, renal plasma flows, and urinary kallikrein excretion rates than S kidneys. These differences tended to be preserved in the cross-transplant groups, and therefore they must be genetically determined intrinsic differences between R and S kidneys. This was especially striking with respect to urinary kallikrein excretion. The rank order of urinary kallikrein excretion was R/R = R/S > S/R = S/S, which implies that it is completely determined by the genotype of the kidney.(ABSTRACT TRUNCATED AT 250 WORDS)
Churchill
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PC
Department of Physiology, Wayne State University, Detroit, Michigan 48201, USA.
Churchill
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MC
Bidani
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Rabito
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SF
D000818:Animals; D001794:Blood Pressure; D004039:Diet, Sodium-Restricted; D004351:Drug Resistance / Q000235:genetics; D005919:Glomerular Filtration Rate; D007610:Kallikreins / Q000652:urine*; D007668:Kidney / Q000502:physiology*; D016030:Kidney Transplantation; D009318:Natriuresis; D051381:Rats; D011919:Rats, Inbred Strains / Q000235:genetics; D012079:Renal Circulation; D012965:Sodium Chloride / Q000494:pharmacology*
D012965:Sodium Chloride; D007610:Kallikreins