Secretion and degradation of insulin and glucagon in carbon tetrachloride-induced liver injury rats

Abstract

To elucidate the mechanism of hyperinsulinemia and hyperglucagonemia in liver diseases, secretion of insulin and glucagon from perfused pancreas and extraction of insulin and glucagon by perfused liver were investigated in carbon tetrachloride inhalated liver injury rats. Fasting plasma insulin and glucagon levels and insulin and glucagon levels after arginine injection (0.25 g/kg) in liver injury rats were significantly higher than those in control rats. Glucagon levels after glucose injection (0.5 g/kg) were slightly increased in the liver injury group. Insulin responses to 16.7 mM glucose and 10 mM arginine from perfused pancreas were similar in liver injury rats and control rats. Glucagon response to 10 mM arginine from perfused pancreas was also similar in liver injury rats and control rats. Insulin extraction by perfused liver in liver injury rats (45 +/- 9%) was significantly (P less than 0.05) lower than that (64 +/- 11%) in control rats, and glucagon extraction by perfused liver was also significantly (P less than 0.05) decreased in liver injury rats (57 +/- 8%) compared with controls (73 +/- 9%). It is concluded that in carbon tetrachloride-induced liver injury rats, hyperinsulinemia and hyperglucagonemia may be dependent on decreased insulin and glucagon extraction by the liver.

Inhibition of glucagon improves splanchnic hyporesponse to terlipressin in cirrhotic rats with blood retention in the gastric lumen

“…The current study confirms previous studies that the plasma concentration of glucagon in CBL rats was significantly increased compared to sham-operated rats [37][38][39]. Moreover, blood gavage caused a significant further increase in plasma glucagon level in both shamoperated and CBL rats.…”

Hepatotoxicity Induced by Diethylnitrosamine Causes no Significant Disturbances of Systemic Glucose Homeostasis in Rats

“…In contrast, post-glucose insulin was very high. Similar findings were reported in the carbon-tetrachloride poisoned rats (Ikeda, Takeuchi, Ito, Murakami, Mokuda, Tominaga and Mashiba 1986) and in patients with chronic liver diseases in whom normal tolerance to intravenous glucose coexisted with very high post-glucose level of peripheral plasma insulin (Lee, Rhee, Lee, Kim, Koh and Min 1987;Pun, Ho and Yeung 1988). Since muscles and adipocytes require higher concentrations of the hormone than the liver for half-maximal insulin effects (DeFronzo, Ferrannini and Hendler 1983), normal insulin action on these tissues was expected.…”

Insulin-induced hypoglycemia stimulates gluconeogenesis from 14C-lactate independently of glucagon and adrenaline releases in rats

“…Glucagon and adrenaline are most important hormones to maintain heaptic glucose production (Vranic et al, 1984;Frizzell et al, 1988). Glucagon is secreted into the portal vein, and largely extracted by the liver (Ikeda et al, 1986). In the present study, peripheral venous glucagon did not change during the first 5 mi Glucagon level could be elevated in the portal vein.…”