Mammotrope heterogeneity in the pituitary gland of European ferret, M ustela putorius Juro: An immunoelectron-microscopic study.

Employing the superimposition technique of electron-microscopic immunocytochemistry ultrastructural heterogeneity of the mammοtropes in the pituitary gland of the European ferret, Mustela putorius furo, was studied. On the basis of the size of their secretory granules, the mammotropes were classified into three subtypes, type-I, type-II and type-Ill, which may correspond to different developmental or physiological states of a single cell type. Simultaneous study of mammotropes and somatotropes in several pairs of serial semithin sections demonstrated the occasional occurrence of bihormonal somatomammotropes/ mammosomatotropes which may represent a transitional stage of the progenitor stem-somatotrope during its differentiation into mammotrope; alternatively it may be a functional intermediate during the cross-transformation of somatotrope into mammotrope or vice versa.

Studies on the biological effects of nitrogen oxides and photochemical oxidants.

The animal studies in mice resulted as follows. Long-term exposure to NO2 at or above 0.5 ppm affected primarily the respiratory organs. The pulmonary effect of NO was slighter than NO2. Nitrosylhemoglobin formation in vivo was much smaller than in vitro strong affinity of NO with hemoglobin. The components other than O3 contained in the photochemically formed oxidant mixtures enhanced the effect of O3 alone. Symptoms of the patients seriously injured by photochemical smog in Japan suggested the different type in quality from the Los Angeles-type smog.