cholecystokinin and Hepatic-Encephalopathy

The distribution of CCK-immunoreactive cells was investigated by the indirect fluorescence method in the cerebral cortex of LEC (Long-Evans Cinnamon) rats which have recently been introduced as a model of jaundice and hepatic encephalopathy. Reduction of CCK-immunoreactive nerve cells was observed in the brains of LEC rats with stage III to V hepatic encephalopathy in comparison with the rats without hepatic encephalopathy. These observations were confirmed by counting the CCK-positive nerve cells at magnification x 125. 3 microscopic fields per animal were immunostained and CCK-immunoreactive nerve cells counted. The number of CCK-immunoreactive cells per field was 28.5 +/- 0.7 (mean +/- SEM, n = 5) in rats without hepatic encephalopathy, and 14.1 +/- 2.0 (n = 3) in rats with stage III to V hepatic encephalopathy. Thus, the number of CCK-immunoreactive nerve cells was significantly less in rats with stage III to V hepatic encephalopathy (p less than 0.05). A decrease in CCK-immunoreactive nerve cells was not observed in the rats with stage I or II hepatic encephalopathy. This study shows that there is a relationship between the severity of hepatic encephalopathy and the number of CCK-immunoreactive nerve cells in the cerebral cortex.

Topics: Animals; Cell Count; Cerebral Cortex; Cholecystokinin; Fluorescent Antibody Technique; Hepatic Encephalopathy; Neurons; Rats

Levels of cholecystokinin (CCK) immunoreactivity and distribution of CCK immunoreactive cells were studied in the cerebral cortex of LEC (Long Evans Cinnamon) rats with hepatic encephalopathy. CCK immunoreactivity in water extract of cerebral cortex of LEC rats with hepatic encephalopathy (n = 7) was 41.5 +/- 2.6 (mean +/- S.E.M. pmol/g wet wt.) and that of LEC rats without encephalopathy (n = 8) was 67.1 +/- 6.9, the difference being significant (P less than 0.01). CCK immunoreactive cells assessed by immunohistochemistry were also markedly decreased in the cortex of LEC rats with hepatic encephalopathy of stage IV. Thus, CCK reduction was observed in the cerebral cortex of LEC rats with hepatic encephalopathy which are provided as a model for analysis of the pathogenesis of acute hepatic encephalopathy.

Topics: Amino Acids; Ammonia; Animals; Brain; Cerebral Cortex; Cholecystokinin; Hepatic Encephalopathy; Immunohistochemistry; Radioimmunoassay; Rats; Rats, Inbred Strains

Recent studies have suggested that decreased excitatory neurotransmission in the brain may contribute to the overall neural inhibition which characterizes the syndrome of hepatic encephalopathy (HE), and that vasoactive intestinal polypeptide (VIP) and cholecystokinin (CCK) may promote neural excitation in the brain. To determine if brain levels of these neuropeptides are altered in HE, measurements were made of the concentrations of immunoreactive VIP (iVIP) and immunoreactive CCK (iCCK) in cerebral cortex, cerebellum and hypothalamus isolated from normal rabbits and rabbits with galactosamin-induced hepatic coma. Hepatic coma was associated with reduced concentrations of iVIP, small molecular weight iCCK and large molecular weight iCCK in the cerebral cortex but not in the cerebellum or hypothalamus. These findings are compatible with decreased VIP- and CCK-mediated neural excitation occurring in the syndrome of HE.

Topics: Animals; Brain; Cerebellum; Cerebral Cortex; Cholecystokinin; Galactosamine; Hepatic Encephalopathy; Hypothalamus; Molecular Weight; Rabbits; Vasoactive Intestinal Peptide

Topics: Amino Acids; Ammonia; Animals; Brain Chemistry; Cholecystokinin; Hepatic Encephalopathy; Liver Diseases; Peripheral Nervous System Diseases; Portacaval Shunt, Surgical; Rats; Rats, Inbred Strains