Somatostatin inhibits the mitogenic effect of thyroliberin.

The effect of somatostatin and of thyroliberin on the mitotic incidence in the organ-cultured anterior pituitary lobe of the rat was investigated, using the colchicine metaphase-arrest technique. It was found that somatostatin added to the culture medium, together with thyroliberin, blocked the mitogenic effect of the latter.     

Efficacy of ethanol as a discriminative stimulus in ethanol-preferring and ethanol-nonpreferring rats

Rats which exhibited a preference for drinking a 6% w/v solution of ethanol in a free choice situation did not differ in their sensitivity to ethanol from animals exhibiting an aversion for ethanol, as measured by leaning rates in a T-maze task in which ethanol served as a discriminative stimulus.     

Metabolic studies of Hg-203 on Chlamydomonas reinhardi

Sterile cultures of Chlamydomonas reinhardi, WT+, were treated with Hg-203 at 25 degrees C to identify probably formed volatile mercury compounds. Experiments were performed with living and dead cells under aerobic or anaerobic conditions, respectively, and the mercury concentration was measured in the system algae/nutrient medium. We found a timerelated decrease of mercury concentration in the cell suspension and the cell-free nutrient medium due to a reduction of Hg++ to Hg0, probably caused by extracellular enzymes; monomethyl or dimethyl mercury could not be detected.     

Aneuploidy as a consequence of senescence and ovariectomy in the golden hamster (Mesocricetus auratus)

The hypothesis of the preferred X-chromosome loss in elder human females was reevaluated in the golden hamster: early castration of females proved that the increase of aneuploid cells is correlated with the loss of the ovaries. But here, and in old females, aneuploidy consisted of random loss of excess of chromosomes, in no case an X-chromosome.     

A species comparison of 2,4-dinitrotoluene metabolism in vitro.

Postmitochondrial supernatants prepared from livers of mice, rats, rabbits, dogs, and monkeys metabolized 2,4-dinitrotulene. The pattern of metabolites was characterized in both sexes of the species examined. In addition, the pattern of metabolites was altered by varying incubation conditions and pretreating male rats with phenobarbital or SKF 525-A.