The Ultrastructure o/Rat-Liver in Carbontetrachloride-Poisoningand Prolonged Hypothermia Summary. During prolonged hypothermia at 25°C (rectal temperature) in rats, stasis occurs in the terminal vesse]s of the liver. Erythrophagocytosis of the Kupffer cells increases. In intensely Iohagocytizing cel]s are not only degenerative changes of the cytoplasmic organelles found, but also crystals. The protective effect of iorolonged hypothermia on the ultrastructure of the epithelium during poisoning with carbon-tetrachloride can be shown to be dependent on the degree of temperature reduction.