Abstract |
Central nervous system (CNS)-induced natriuresis was investigated in nonascitic rats with CCl4-induced cirrhosis (CTC rats) under pentobarbital anesthesia. At baseline, urine sodium output (UNa+V, in mumol.min-1.100 g body wt-1) (-30%, P less than 0.01) and mean arterial pressure (MAP, in mmHg) (-12%, P less than 0.001) were significantly reduced in CTC rats (n = 32) compared with matched controls (n = 34). In response to intracerebroventricular infusion of sodium-rich (349 mM) artificial cerebrospinal fluid (Na(+)-CSF infusion), UNa+V was significantly higher in CTC rats (2.8 +/- 0.3; n = 15) than in controls (1.7 +/- 0.2; n = 17; P less than 0.01); no differences were found in pressor changes (24 +/- 3 vs. 19 +/- 2). A similar but normal sodium CSF (150 mM) infusion did not influence UNa+V or MAP in any group (n = 12, both). In contrast, CTC rats (n = 5) showed, compared with controls (n = 5), significantly reduced natriuretic (UNa+V, 6.9 +/- 0.5 vs. 12.4 +/- 0.9; P less than 0.001) and pressor (+16 +/- 3 vs. +31 +/- 2; P less than 0.01) responses to an intravenous hypertonic sodium overload. Natriuresis induced by Na(+)-CSF infusion was related to increases in creatinine clearance (similar in both groups) and in fractional sodium excretion, which was significantly higher in CTC rats (5.90 +/- 0.15%) than in controls (3.65 +/- 0.14%; P less than 0.01). In summary, CNS-dependent efferent natriuretic mechanisms were preserved in CTC rats and were able to reverse renal tubular sodium retention in these animals. It is proposed that Na(+)-CSF infusion may be a useful tool for the study of renal sodium retention in experimental liver cirrhosis.
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Authors | I Colina, J Quiroga, F Guarner, A Purroy, J Prieto |
Journal | The American journal of physiology
(Am J Physiol)
Vol. 260
Issue 6 Pt 1
Pg. G972-6
(Jun 1991)
ISSN: 0002-9513 [Print] United States |
PMID | 2058681
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Saline Solution, Hypertonic
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Topics |
- Animals
- Blood Pressure
(drug effects)
- Carbon Tetrachloride Poisoning
(physiopathology)
- Cerebral Ventricles
(drug effects, physiology, physiopathology)
- Infusions, Parenteral
- Liver Cirrhosis, Experimental
(physiopathology)
- Male
- Natriuresis
- Rats
- Rats, Inbred Strains
- Reference Values
- Saline Solution, Hypertonic
(administration & dosage, pharmacology)
- Time Factors
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