Effect of low doses of the hydra peptide morphogen on protein biosynthesis in the intact and regenerating rat liver

The dependence of ornithine decarboxylase (ODC) activity on hydra peptide morphogen doses has been established. The parameters of protein synthesis were determined in normal and regenerating rat liver, using the peptide in a dose of 20 micrograms/kg body weight, initiating maximum enzyme activity. It was established that intraperitoneal injection of the peptide in partially hepatectomized animals stimulated ODS activity in dose-dependent manner and was dome-shaped. The peptide injection in intact animals does not affect the intensity of 3H-leucine inclusion into the liver protein and the protein content in rat liver. However, the peptide injection in partially hepatectomized animals increased the level of 3H-leucine inclusion into the protein of regenerating liver and stimulated protein accumulation in this type of tissue.     

Specific binding of a synthetic antioxidant from a series of spatially screened phenols, H3-phenozan, with isolated rat enterocytes

Specific binding of gamma-(4 hydroxy-3,5-ditret. butyl-phenol) propionate (phenozan), a synthetic water-soluble screened phenol with antioxidant activity, with isolated rat enterocytes has been demonstrated. The Scatchard analysis of binding isotherms revealed two types of 3H-phenozan binding sites. It is concluded that the effect of synthetic screened phenol antioxidants on cellular activity is the result of two mechanisms of action--alteration of physicochemical properties of membrane lipids caused by the inhibitors of free-radical reactions and specific binding of these compounds to cell plasma membranes.     

Development of magnocellular neurosecretory neurons in embryonic hypothalamic tissue transplanted into the cavity of the 3d cerebral ventricle of adult rats

Magnocellular neurosecretory cell (MSC) ontogenesis was comparatively assessed in normal rat hypothalamus and in fetal hypothalamic tissue transplanted into the third ventricle of the adult rat brain. 3H-thymidine uptake has shown that the time of origin of NSC in grafted tissue and supraoptic nucleus of normal rat fetuses was similar. NSC pericarions in grafts were well developed and contained neurosecretory material (NSM). Nuclear and nucleolar volumes did not differ from those in adult animals. Water deprivation was followed by a significant increase in nuclear and nucleolar volumes and NSM content in pericarions of grafted tissue, which suggests that raised synthetic activity was not accompanied by an increased NSM release. It is concluded that proliferation and specific differentiation of NSC precursor cells are invariably determined by genetic factors. The origin of neurosecretory nuclei and their specific connections is considerably influenced by conditions of tissue surroundings.