PubMed Health⌕ Search

Biomedical subjects

G S Gupta

Publications and source records attributed to G S Gupta.

At least 109 records · Page 6Linked to original sources
PubMed1975

Radiation effects on alkaline phosphatase and glucose-6-phosphatase in anatomically different regions of mouse intestine.

The effect of gamma irradiation on alkaline phosphatase and glucose-6-phosphate has been studied in three anatomically different regions of the small intestine at a surface dose of 400 R. Both the enzymatic activities were shown to be enhanced in duodenum, jejunum and ileum 24 hours after irradiation. The activity of alkaline phosphatase on day 3 tendeed to be low as compared to day 1 post irradiation, but glucose-6-phosphatase continued to rise even after day 3. Maximum rise of glucose-6-phosphatase was observed in the jejunum. On day 9, alkaline phosphatase was diminished below the controls in the whole of intestine, but appeared to be normal on day 10. Glucose-6-phosphatase in duodenum and jejunum on the other hand was comparable to that of control mice; but in ileum, the activity of this enzyme was below the normal values. Physiological significances of these enzymes in intestine has been discussed.

Alkaline Phosphatase↗
PubMed1975

Radiation effects on rat testes. VIII. Kinetic properties of hydrolases following partial body gamma irradiation of rats.

Kinetic properties such as Michaelis constant (Km), maximum velocity (Vmax), temperature coefficient (Q10) and energy of activation (Ea) for hydrolysis of adenosine-5'-phosphate at pH 9.5 and sodium pyrophosphate at pH 8.35 by normal and radiated testes supernatants have been described. Kinetic parameters are related to respective phosphohydrolases (phosphatases). (1) Km values for 5'nucleotidase and inorganic pyrophosphatase of normal testis were determined as 1.25 X 10(-3)M and 0.81 X 10(-3)M respectively; (II) Vmax correspond to 318 mug P/15 min and 430 mug P/15 min for 100 mg tissue respectively; (III) Q10 for 5 nucleotidase is 1.7 and for inorganic pyrophosphatase is 4.2 at a temperature 10-30degreesC; (IV) Ea for hydrolysis of AMP and sodium pyrophosphate were calculated by Arrhenius plots as 17000 and 9000 cal/mol. (V) Km values for irradiated enzymes are similar to the control values suggesting that the binding capacities of these enzymes with their substrates remain unaffected after radiation; (VI) Vmax for radiated enzymes correspond to a value of 500 mug P/100 mg tissue/15 min for 5'nucleotidase and 118 mug P/100 mug tissue/15 min for inorganic pyrophosphatase; (VII) 110 for 5'nucleotidase is 2.2 and inorganic pyrophosphatase 1.16 at 10-30degreesC; (VIII) Ea for irradiated 5'nucleotidase is comparable to those of normal rats whereas for inorganic pyrophosphatase Ea is moderately declined. The observed changes have been related to the different types of metabolic activity in germinal and nongerminal cells of testes.

Adenosine Monophosphate↗
PubMed1975

Radiation effects on rat testes. IX. Studies on oxidative enzymes after partial body gamma irradiation.

Oxidative enzymes in the rat testes have been studied after gamma irradiation. The role of these enzymes in relation to spermatogenesis and steroidogenesis after radiation injury to testis has been discussed. Loss of succinic dehydrogenase and sorbitol dehydrogenase reflects the losts of germ cell population. Malic enzyme and malic dehydrogenase seem to the related to the deficiency of steroid hormones, whereas increase in glucose-6-phosphate dehydrogenase and NADP isocitric dehydrogenase is due to secondary stimulation of pituitary.

Animals↗