Portal fibroblasts and myofibroblasts in baboons after long-term alcohol consumption.

The relative abundance of fibroblasts and myofibroblasts in the portal tracts was assessed in liver biopsy specimens of baboons that developed fatty liver and perivenular fibrosis after alcohol (ethanol) consumption. Fourteen baboons pair-fed with diets containing alcohol, or isocaloric carbohydrate, for up to four years were studied. No fibrosis was observed in the portal tracts of these baboons. The number of mesenchymal cells per 1,000 sq microns of the portal tissue was not changed after alcohol consumption. Electron microscopy demonstrated no increase in the number of fibroblasts, myofibroblasts, or other mesenchymal cells. In view of an increased number of myofibroblasts and fibroblasts in association with the development of perivenular fibrosis as previously reported, the results herein suggest that mesenchymal cells in the portal tracts lack the proper stimuli for proliferation after alcohol consumption.