An ultrastructural study on a new type of hepatic perisinusoidal cell in fish

Summary A new type of perisinusoidal cell containing numerous microfilaments is described for the first time. It is found in abundance in the livers of both marine and freshwater fish. These perisinusoidal cells are situated within the space of Disse and adhere firmly through desmosomes both to sinusoidal endothelial cells and to hepatocytes. The cytoplasmic microfilaments are striking and make these cells readily distinguishable from the perisinusoidal fat-storing cells of Ito. Although the function of these cells is not known, the observations presented here suggest that they may provide a supportive framework within the liver.Supported in part by Grants # GM92 and # ES07017     

The influence of uncouplers on proton-sugar symport in Saccharomyces fragilis

Uncouplers of oxidative phosphorylation inhibit proton-sugar symport in Saccharomyces fragilis. However, they do not induce efflux of accumulated sugar. It is shown that the effect cannot be explained by uncoupler-induced alterations in the transmembrane potential or transmembrane pH difference. It is also indicated that a decrease in intracellular pH is not involved in inhibition of sugar transport. It is argued that inhibition of transport by uncouplers is most likely caused by a direct interaction with the translocator.