Histochemical studies on phosphorylase activity in the tissues of the albino rat under normal and experimental conditions

Summary Various substrate mixtures have been tested for the histochemical demonstration of phosphorylase in tissue blocks. These studies indicate that phosphorylase activity, cytological detail and localization of the reaction product are optimally demonstrated when tissue blocks are incubated for one hour or longer in a medium containing high concentrations of G-1-P, ATP and PVP.Abbreviations AMP adenosine-5-monophosphate - ATP adenosine-5-triphosphate - EDTA ethylenediamine-tetraacetic acid - G-1-P glucose-1-phosphate - PPa active phosphorylase - PPb inactive phosphorylase - PVP polyvinyl pyrrolidone     

Turkey liver xanthine dehydrogenase. Relation between nicotinamide-adenine dinucleotide oxidoreductase activity and the content of functional enzyme.

The turkey liver xanthine dehydrogenase-catalysed oxidation of NADH by Methylene Blue, by ferricyanide or by O2 is not dependent on the integrity of the active-centre persulphide groups. By contrast, the NADH-dichlorophenol-indophenol oxidoreductase and NADH-trinitrobenzenesulphonate oxidoreductase activities are directly proportional to the content of functional enzyme. These findings help to identify the sites of egress of electrons to oxidizing substrates.     

Histochemical detection of hemp trichomes and their correlation with the THC content

Authors investigated some fiber and some hashish hemp sorts concerning their trichomes on the leaves. Histochemical reactions were developed using the Fast Blue Salt (FBB) reagent applied so far only thin layer chromatography. Glandular hairs were found giving positive reactions due to cannabinoids contained by the cells. The electron microscopic features were studied and the cannabinoid content was measured with GC. A correlation was found between the number of typical glandular hairs and cannabinoid content.     

Histochemical changes in the testes of lead induced experimental rats

The experiments were performed on mature male rats divided in five groups, one control and four experimental in which the animals received 1 mg, 2 mg, 4 mg and 6 mg/kg body weight lead acetate intraperitoneally respectively, over a period of 30 days. ALA-D and lead was estimated in the blood by the use of atomic absorption spectrophotometer and ATP-ase, AMP-ase, Alk-ase were histochemically localized. Significant increase in blood and testis of lead levels along with decrease of ALA-D levels were observed. Changes in the testicular tissue were encountered. Other details concerned with the damage of the testicular tissue are discussed.     

Histochemical demonstration of succinic dehydrogenase activity during sequential molar development in the Swiss albino mouse

Summary Applying the ditetrazolium salt (Nitro-BT) method for succinic dehydrogenase, murine molar teeth were studied sequentially from the cap stage of development through the appositional stages of odontogenesis. Reaction-distribution and intensity varied relative to the developmental stage as well as the zone of maturation within a given stage. The peripheral cells of the parent dental lamina exhibited some activity, as did the outer enamel epithelium of the bell stage. During the period of matrix apposition, components of the stratum intermedium, ameloblastic zone and odontoblastic layer region of the dental papilla demonstrated intense enzymatic activity. Cells actively engaged in enamel matrix production demonstrated activity in the basal and distal cell segments. High activity continued in the papillary layer of the enamel organ, as well as in the cells of the dental sac during the postamelogenic period.Supported by PHS Grant No. 2800-02, National Institute of Dental Research, National Institutes of Health.