When BALB/c mice (young and adult animals of both sexes) were infected intraperitoneally with 103 viable cells of Francisella tularensis (102 50% lethal dose), all mice in these groups died on day 4. Reductions in thymus weights and in numbers of thymic cortex lymphocytes were observed in all the groups, but the decline was not so severe in the young females. Increases of plasma corticosterone in the adult males began 1 day after infection, but in the young females, the levels did not increase until day 3, the same days on which the respective thymus weights began to decline. Depletion of the thymus weights in the infected mice was prevented by adrenalectomy. The lymphocytes of the thymus (T)-dependent areas in peripheral lymphoid tissues in all groups were destroyed. By using an electron microscope, we found a large quantity of F. tularensis within the macrophages in the T-dependent areas but not in the thymus. The destruction of lymphocytes in the T-dependent areas was not prevented by adrenalectomy. Therefore, it was concluded that the weight reduction of the thymus is due to the stress of the F. tularensis infection. However, we think other mechanisms are responsible for the depression of lymphocytes in the T-dependent areas of peripheral lymphoid tissues.

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The activity and the histochemical localization of gamma-GTP in the liver of chronic alcoholics were investigated. Mean serum gamma-GTP activity in alcoholics was 542.5 +/- 337.9 milliunits/ml, and that of patients with nonalcoholic liver disease was 34.3 +/- 22.6 milliunits/ml. Hepatic gamma-GTP activity in alcoholics was significantly increased compared to that in control patients (15.62 +/- 9.29 versus 4.04 +/- 2.67 units/g of liver; p less than 0.001). A significant correlation was observed between hepatic and serum gamma-GTP activity. Light microscopically, a marked gamma-GTP activity was found in the bile canaliculi and a diffuse activity in the cytoplasm in alcoholic livers. By contrast, in the livers of nonalcoholic patients, only slight activity was observed in the bile canaliculi. The electron micrographs showed the enzyme was localized in the microvilli of both the bile canalicular and plasma membranes and the endoplasmic reticulum near the mitochondria in alcoholics. But a very low activity was demonstrated in the plasma membranes in the livers of nonalcoholic patients.

Nonselect Wistar rats and high-and stable-avoidance and low-variability (HA) rats were exposed to 100 ppm toluene vapor or air seven hours a day from the 13th day of gestation to 48 days of age. After termination of toluene exposure, the rats were examined by the Sidman avoidance test for 10 days. There was no difference between the toluene-exposed group and the control in the appearance of developmental signs in either the nonselect Wistar rats of HA rats. In the exposed HA males, learning acquisition was slow, and the individual variation in avoidance rates was as large as that of the nonselect rats. In the control HA males, avoidance learning was acquired rapidly and stabilized. A significant difference in avoidance was indicated between the exposed and the control HA rats. In HA females, learning acquisition and speed and magnitude of individual variation in avoidance rates in the exposed rats did not differ greatly from those of the controls. Slow learning acquisition and a large magnitude of individual variation in avoidance rates were displayed in the male and female nonselect Wistar rats. But in both the male and female controls of the nonselect rats, learning acquisition and individual variation did not differ from those of the exposed nonselect rats. No difference in avoidance was indicated between the exposed rats and the controls in either males or females.