Histochemical and Ultrastructural Studies of Hepatic Fibrogenesis; Its Initiation and the Effect of Dexamethasone in Rats

ABSTRACT

Intralobular fibrogenesis of the liver following hepatocellular damage has long been a controversial subject in regard to its initiation and prevention. To investigate the site of hepatic fibrogenesis and the effect of glucocorticoids during the early stage of hepatic fibrogenesis, dexamethasone was administered in a daily dose of 8 mg/rat following a sing1e dose of CCl4 to induce hepatic necrosis with or without combination of vitamin A to Stimulate lipocytes. Light and electron microscopic examinations of the liver at 2, 4, 6, 8 and 10 days after CCl4, vitamin A and dexamethasone treatment demonstrated that hepatocellular damage stimulated perisinusoidal lipocytes which in turn actively produced collagens. Concomitant administration of vitamin A enhanced stimulation of lipocytic activity and consequently increased collagen formation, while administration of dexamethasone suppressed lipocytic activity leading to an inhibition of collagen formation.