[Experimental model of induction in the rat of rapidly developing biliary cirrhosis in peripartal nodular cirrhosis]. / Modello sperimentale di induzione nel ratto di una cirrosi biliare a rapida evoluzione in cirrosi nodulare periportale.

The treatment with CCl4 and progesterone subsequent the common biliary duct ligature induced, in the rat, after 4-5 weeks, a cirrhotic picture characterized by an early and strong biliary epithelium proliferation followed by a perilobular fibrosis with a concentric sclerosis as in true perilobular cirrhosis.

In vivo total body water assessment by total body electrical conductivity in rats suffering perturbations of water compartment equilibrium.

Total body electrical conductivity (TOBEC) is a simple and non-invasive method for the assessment of body composition in vivo. Information regarding the applicability of TOBEC in the condition of abnormal fluid balance is scarce. In the present paper we give the results of the comparison between TOBEC and total body water (TBW; assessed by the tritium dilution technique) in three groups of animals: (1) healthy (n 17), (2) expanded fluid volume by secondary biliary cirrhosis (SBC; n 9) and (3) Furosemide-treated rats (n 9). The TOBEC score and TBW by tritium dilution were found to be highly correlated in the pooled sample (r 0.90) and in normal (r 0.87), SBC (r 0.73) and Furosemide-treated (r 0.89) rats. However, the relationship between TOBEC and TBW, described by least-squares regression analysis, was found to be similar for SBC and normal rats but was significantly different for Furosemide-treated and normal rats. These findings suggest that TOBEC is unable to track TBW accurately when the ratio between intracellular and extracellular water is chronically or acutely altered.

Changes in fibronectin production in rat liver during cirrhotic evolution due to treatment with CCl4 and steroid hormones: correlation with plasmatic fibronectin.

Previous our studies showed that some steroid hormones, as pure crystalline Progesterone (pPc) and 17-alpha-hydroxyprogesterone capronate (17 alpha HPC) heightened the cirrhogenic action produced in rat liver by carbon tetrachloride. Medroxyprogesterone (MPA), however, did not appear to promote cirrhosis, but increased just steatosis. In the present paper, we have studied the above mentioned steroid hormones for their possible capability of inducing changes in plasma fibronectin concentration. For this purpose, the soluble plasma fibronectin level was measured in female rats 45 days after CCl4-induced cirrhosis, and it was compared with the insoluble fibronectin of liver (detected by immunostaining) and the collagen content in the organ. The results obtained show that, after treatment with CCl4 and MPA, both plasma and liver fibronectin content strongly increases, whereas liver collagen content lowers. However, after treatment with CCl4 alone or in association with the other two steroid hormones, any changes in fibronectin content is not observable, but, on the contrary, is evident a heightened collagen production associated with a cirrhotic change of liver.

[Morphologic changes in the liver of rats treated with monensin]. / Alterazioni morfologiche in fegati di ratti trattati con monensina.

Monensin, a carboxylic ionophore, collapse Na+ gradient across biological membranes, increases intracellular pH and affects many processes involved in transport, posttranslational modification and secretion of proteins, moreover endocytosis and degradation in lysosomes. Concerning the liver, the action of monensin in vitro or in perfused liver, showed an altered secretion of protein and altered transport of VLDL; in bile-fistula rats, monensin caused a decrease of bile flow, altered protein profile and bile acids secretion. Because the effects of monensin seem to be complicated, in this note it has been studied the action of monensin on the morphology of liver cells to have a picture not only of the parenchymal cells, but also of the sinusoidal cells, which cooperation with the general liver functions become increasingly evident. The results obtained after staining of liver biopsies with Sudan Black, Sudan III and Sudan IV showed that monensin induces a diffuse cholestasis and islands of hepatocytes in steatosis, in agreement with the data in literature. Cells lining the sinusoid with phagocytic activity and that might be identified with fat-storing cells, showed an increase of their lipid droplets that might be attributed to vitamin A.

[The effect of hypophysectomy on liver regeneration in the rat]. / Influenza dell'ipofisectomia sulla rigenerazione epatica del ratto.

Liver regeneration after partial hepatectomy in Wistar rats, hypophysectomised and otherwise has been studied. In almost all hypophysectomised rats, the regenerative processes were much less evident than in the non-hypophysectomised controls; only some hypophysectomised animals showed effective liver regeneration through an as yet unclear mechanism.

[The role of the urinary hydroxyproline level in the screening for collagen diseases]. / Importanza del dosaggio dell'idrossiprolina nelle urine come screening delle malattie del collagene.

Modifications in urinary hydroxyproline concentrations were studied in various collagen degradation diseases. A significant increase in hydroxyprolinuria was found in both men and women with Paget's disease in all age groups considered. Significant increases were found in men with the same pathologies. Rheumatoid arthritis also increased urinary hydroxyproline in both males and females. It therefore seems that bone tissue pathologies are reflected in the metabolism of hydroxyproline as are articular connective tissue pathology strictly related to it.

[Diverse action of 17-alpha-hydroxyprogesterone caproate and medroxyprogesterone acetate on the biosynthesis of collagen and cirrhogenous course of CC14-induced hepatic lesions in rats]. / Diversa azione del 17-alpha-idrossiprogesterone capronato e del medrossiprogesterone acetato sulla biosintesi del collagene e sulla evoluzione cirrogena delle lesioni epatiche da CC14 nel ratto.

The administration of medroxyprogesterone acetate to rats did not induce rapidly progressing cirrhosis in livers damage by carbon tetrachloride, as had occurred after the administration of 17-alpha-hydroxyprogesterone caprate. Even after two months' treatment with medroxyprogesterone acetate and CC14, the cirrhosis did not reach the levels obtained in a single month with the association of 17-alpha-hydroxyprogesterone and CC14.