Morphologic and Biochemical Changes in Dogs After Portacaval Shunt Plus Bile Fistula or Ileal Bypass: Failure of Bile Fistula or Ileal Bypass to Prevent Hepatocyte Atrophy

Abstract

External biliary fistula (BF) or ileal bypass (IB) was performed in dogs at the time of or 2 weeks after portacaval shunt (PCS). The pathologic changes in the dog livers 2 to 4 weeks later were compared to those caused by PCS alone. Histopathologic differences between PCS alone vs. PCS plus BF or IB could not be found. Thus, the experiments did not confirm recent observations by others in rats that BF prevents or reverses the hepatic injury of PCS. As estimated by plasma mevalonic acid determinations, the increase in hepatic cholesterol synthesis that is characteristic after BF or IB was suppressed in animals with PCS. BF and m reduced but did not eliminate the postprandial elevation in serum bile acid that occurs after PCS. The findings have possible relevance in planning the treatment of patients with familial hypercholesterolemia with the combined use of PCS and lB.Completely diverting portacaval shunt (PCS), also called Eck's fistula, has been used for its effect upon the metabolism of patients with glycogen storage disease (1), familial hypercholesterolemia (2, 3), and aI-antitrypsin deficiency (4). The metabolic palliation in these diseases has been ascribed in part to the hepatocyte alterations caused by portal diversion including atrophy, deglycogentation, fat accumulation, increased mitosis, and major ultrastructural disruptions (2,(4)(5)(6)(7)(8)(9). These changes are identical in rats, dogs, and humans (5). Thus, research with any of these species should be applicable to all in spite of the fact that humans are unusually resistant to the hepatic encephalopathy that may complicate PCS.Balabaud et a1. (10) and Bioulac et a1. (11) have

Quantitative Studies of Liver Atrophy After Portacaval Shunt in the Rat

“…Because zone 3 contains mitochondria and peroxisomes, it can be assumed that there also is an associated reduction in metabolic activity within these hepatocytes. These findings confirm previous reports using light microscopy [5,6,8,9] and electronic microscopy [11][12][13][14][15][16][17] in this animal model. We also found a reduction in the nuclear area of hepatocytes in zone 1 and zone 3 comparable with results reported by other authors [16,30,31].…”

“…In a recent study, we [4] found that PCS, in the absence of liver dysfunction, produces testicular atrophy by reductions in mitosis, maturation arrest, and increased apoptosis of the germinal epithelium of the semineferous tubules. Several authors [5][6][7][8][9][10] have studied the morphological changes of the liver in PCS operated rats. Alteration in both the cellular and nuclear morphology was observed, together with the loss of glucose-6-phosphatase, mainly in the centrilobular areas of the liver [10].…”

Liver regeneration

“…Diversion of the portal vein flow to vena cava (portacaval shunt) forces insulin to bypass the liver. Liver atrophies to about 1/3 of its size (Bucher, 1976;Bucher and Weir, 1976;Thompson et al, 1983;Evarts et al, 1986). Administration of insulin directly to the liver in animals with experimental portacaval shunts reverses hepatic atrophy, and is associated with rapid hepatocyte proliferation.…”

Μελέτη Της Αναγεννητικής Ικανότητας Του Ήπατος Μετά Από Μερική Ηπατεκτομή

“…Αποτελούν μέλη μίας οικογένειας πρωτεϊνών που σχηματίζουν ένα πολύπλοκο σηματοδοτικό δίκτυο μεταξύ κυττάρων σε φάσεις διαφοροποίησης και πολλαπλασιασμού (Mumm and Kopan 2000;Baron, Aslam et al 2002;Baron 2003). Thompson, Porter et al 1983;Evarts, Raab et al 1986 (Webber, Bruix et al 1998).…”