DEPRESSED SENSITIVITY OF THE HEPATOPORTAL NACL RECEPTORS IN RATS WITHCARBON TETRACHLORIDE-INDUCED LIVER-CIRRHOSIS

In normal rats, the activity of the hepatoportal NaCl-sensitive affere nt nerves is increased by portal injection of hypertonic NaCl. In the present article, we have found this effect to be markedly reduced in r ats with CCl4-induced liver cirrhosis (CT rats). Liver tissue norepine phrine content, a marker of tissue innervation, was also decreased in the treated rats. Over the 12 wk CCl4-treatment period, no significant difference in Na balance was found between control and CT rats when b oth groups were given normal NaCl (0.45%) food. However, when both wer e given high NaCl (8%) food, the Na balance of CT rats was positive an d greater than that of controls. These results indicate that the sensi tivity of the hepatoportal NaCl receptors is decreased even when the d egree of liver cirrhosis is slight. This mechanism plays an important role in maintaining Na balance during intake of high NaCl food.