Calmodulin dependency of calcitonin action on glucose-6-phosphatase and phosphorylase a activites in the liver of rats

1983 ◽  
Vol 104 (4) ◽  
pp. 490-494 ◽  
Author(s):  
Masayoshi Yamaguchi ◽  
Kaoru Momose
Keyword(s):  
Body Weight ◽  
Enzyme Activity ◽  
Phosphatase Activity ◽  
Calcium Ion ◽  
Calcium Content ◽  
Hepatic Glycogen ◽  
Maximal Effect ◽  
Hepatic Microsomes ◽  
Glycogen Particles ◽  
Intact Rats

Abstract. The calmodulin dependency of calcitonin (CT) action on glucose-6-phosphatase and phosphyrylase a activities in the liver of rats was investigated. A single sc administration of CT (synthetic [A1,7] eel CT; 80 MRC mU/100 g body weight) produced significant increases in calcium content and glucose-6-phosphatase activity in the hepatic microsomes of intact and thyroparathyroidectomized rats. These increases in enzyme activity were significantly inhibited by W-7 (100 μm), with a concentration which showed maximal effect. However, this inhibition was less than 50% of the enzyme activity increased by CT administration. Meanwhile, CT produced significant increases in calcium content and phosphorylase a activity in the hepatic glycogen particles from intact rats. However, this increase in enzyme activity was not influenced significantly by W-7 (100 μm), suggesting that the calcium ion may directly activate the enzyme. These results suggest that the increase in microsomal glucose-6-phosphatase activity of rat liver mediated by cellular calcium following CT administration may partly depend on calmodulin.

Calcitonin increases calcium content and glucose-6-phosphatase activity in hepatic microsomes of rats

1983 ◽  
Vol 102 (4) ◽  
pp. 572-576 ◽  
Author(s):  
Masayoshi Yamaguchi ◽  
Kaoru Momose
Keyword(s):  
Body Weight ◽  
Phosphatase Activity ◽  
Calcium Ion ◽  
Marked Reduction ◽  
Calcium Content ◽  
The Other ◽  
Appreciable Effect ◽  
Other Hand ◽  
Hepatic Microsomes

Abstract. The effect of calcitonin (CT) on calcium content and glucose-6-phosphatase activity in the hepatic microsomes of rats was investigated. A single sc administration of CT (80 MRC mU/100 g body weight) produced a significant increase in microsomal calcium content and a corresponding elevation of microsomal glucose-6-phosphatase activity. An appreciable effect of CT was observed at a dose of 20 MRC mU/100 g body weight. On the other hand, the removal of calcium by 10 mM EGTA washing of the microsomes caused a marked reduction of glucose-6-phosphatase activity raised by CT administration. The addition of calcium ion at the amount of 10−2– 103 nmoles Ca2+ per mg protein in the microsomes produced a significant increase in glucose-6-phosphatase activity. The present results suggest that microsomal calcium increased by CT administration activates glucose-6-phosphatase in the hepatic microsomes of rats.

l-THYROXINE, CORTISOL AND DIET AFFECT THE LEVEL OF AMYLASE IN THE PAROTID GLAND OF DEVELOPING RATS

1980 ◽  
Vol 87 (1) ◽  
pp. 65-71 ◽  
Author(s):  
MASAYOSHI KUMEGAWA ◽  
NORIHIKO MAEDA ◽  
TOSHIHIKO YAJIMA ◽  
TAISHIN TAKUMA ◽  
EIKO IKEDA ◽  
...  
Keyword(s):  
Body Weight ◽  
Enzyme Activity ◽  
Parotid Gland ◽  
Amylase Activity ◽  
Synergistic Effects ◽  
Dietary Factors ◽  
Adult Rats ◽  
Early Increase ◽  
Adrenalectomized Rats ◽  
Intact Rats

The effects of cortisol (10 μg/g body weight) and l-thyroxine (T4; 0·2 μg/g body weight) on the activity of parotid gland amylase in young rats were investigated. Administration of cortisol or T4 for 5 consecutive days from day 5 after birth caused the precocious appearance of amylase, T4 having almost twice the effect of cortisol. Cortisol and T4 did not have synergistic effects. In thyroidectomized-adrenalectomized rats, T4 increased amylase activity but cortisol did not. The increase in enzyme activity after day 20 was much less in rats thyroidectomized on day 10 than in rats adrenalectomized on day 10. These results suggest that T4 has a direct effect on the early increase of amylase activity (days 15–25) and that the action of glucocorticoid requires the presence of endogenous thyroid hormones. The hormone-induced level of amylase in intact rats was less than that of normal adult rats. Forced weaning of intact rats resulted in a further increase in amylase activity, suggesting that further amylase accumulation (after day 25) may be due to dietary factors.

scholarly journals Increase in alkaline phosphatase activity in calvaria cells cultured with diphosphonates

1979 ◽  
Vol 183 (1) ◽  
pp. 73-81 ◽  
Author(s):  
R Felix ◽  
H Fleisch
Keyword(s):  
Alkaline Phosphatase ◽  
Protein Synthesis ◽  
Enzyme Activity ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Heat Inactivation ◽  
High Concentration ◽  
Control Value ◽  
Km Value ◽  
Inhibitor Of Protein Synthesis

1. Dichloromethanediphosphonate and to a lesser degree 1-hydroxyethane-1,1-diphosphonate, two compounds characterized by a P-C-P bond, increased the alkaline phosphatase activity of cultured rat calvaria cells up to 30 times in a dose-dependent fashion. 2. Both diphosphonates also slightly inhibited the protein synthesis in these cells. 3. Thymidine, an inhibitor of cell division, did not inhibit the induction of the enzyme, indicating that the increase in enzyme activity was not due to the formation of a specific population of cells with high alkaline phosphatase activity. 4. The effect on alkaline phosphatase was suppressed by the addition of cycloheximide, an inhibitor of protein synthesis. 5. After subculturing the stimulated cells in medium without diphosphonates, the enzyme activity fell almost to the control value. 6. Bovine parathyrin diminished the enzyme activity of the control cells and the cells treated with dichloromethanediphosphonate; however, at high concentration the effect of parathyrin was greater on the diphosphonate-treated cells than on the control cells. 7. The electrophoretic behaviour, heat inactivation, inhibition by bromotetramisole or by phenylalanine, and the Km value of the induced enzyme were identical with that of the control enzyme.

scholarly journals Properties of cytosolic components activating rat hepatic 5-deiodination in the presence of NADPH

1986 ◽  
Vol 234 (2) ◽  
pp. 391-398 ◽  
Author(s):  
K Sawada ◽  
B C W Hummel ◽  
P G Walfish
Keyword(s):  
Enzyme Activity ◽  
Glutathione Reductase ◽  
Rat Liver ◽  
Column Chromatography ◽  
Reduced Glutathione ◽  
Hydrogen Acceptor ◽  
Simultaneous Addition ◽  
Heat Stable ◽  
Hepatic Microsomes ◽  
Normal Rat

The effects of cytosol, NADPH and reduced glutathione (GSH) on the activity of 5′-deiodinase were studied by using washed hepatic microsomes from normal fed rats. Cytosol alone had little stimulatory effect on the activation of microsomal 5′-deiodinase. NADPH had no stimulatory effect on the microsomal 5′-deiodinase unless cytosol was added. 5′-deiodinase activity was greatly enhanced by the simultaneous addition of NADPH and cytosol (P less than 0.001); this was significantly higher than that with either NADPH or cytosol alone (P less than 0.001). GSH was active in stimulating the enzyme activity in the absence of cytosol, but the activity of 5′-deiodinase with 62 microM-NADPH in the presence of cytosol was significantly higher than that with 250 microM-GSH in the presence of the same concentration of cytosol (P less than 0.001). The properties of the cytosolic components essential for the NADPH-dependent activation of microsomal 5′-deiodinase independent of a glutathione/glutathione reductase system were further assessed using Sephadex G-50 column chromatography to yield three cytosolic fractions (A, B and C), wherein A represents pooled fractions near the void volume, B pooled fractions of intermediate Mr (approx. 13 000), and C of low Mr (approx. 300) containing glutathione. In the presence of NADPH (1 mM), the 5′-deiodination rate by hepatic washed microsomes is greatly increased if both A and B are added and is a function of the concentrations of A, B, washed microsomes and NADPH. A is heat-labile, whereas B is heat-stable and non-dialysable. These observations provide the first evidence of an NADPH-dependent cytosolic reductase system not involving glutathione which stimulates microsomal 5′-deiodinase of normal rat liver. The present data are consistent with a deiodination mechanism involving mediation by a reductase (other than glutathione reductase) in fraction A of an NADPH-dependent reduction of a hydrogen acceptor in fraction B, followed by reduction of oxidized microsomal deiodinase by the reduced acceptor (component in fraction B).

Role of the Splanchnic Nerve and the Adrenal Medulla in the Genesis of ‘Preoptic Pulmonary Edema’

1956 ◽  
Vol 184 (2) ◽  
pp. 351-355 ◽  
Author(s):  
Frederick W. Maire ◽  
Harry D. Patton
Keyword(s):  
Body Weight ◽  
Protective Effect ◽  
Pulmonary Edema ◽  
Adrenal Medulla ◽  
Adrenal Glands ◽  
Splanchnic Nerve ◽  
Lung Edema ◽  
Splanchnic Nerves ◽  
Intact Rats

The pulmonary edema which follows preoptic lesions in rats is prevented by antecedent bilateral section of the splanchnic nerves. Intravenous epinephrine in doses exceeding 0.0125 mg/100 gm body weight causes fatal lung edema in rats comparable to that produced by preoptic lesions. Moreover, extracted pressor amines from rat adrenal glands cause lung edema, often fatal, when injected into the donor or into intact rats. However, adrenal demedullation does not prevent lung edema following preoptic lesions. Hence the protective effect of splanchnectomy against preoptic lesions is not wholly due to adrenal denervation. It is tentatively suggested that preoptic lung edema results from overloading of the pulmonary circuit owing to splanchnic mediated constriction of visceral venous reservoirs. Liver and spleen weights of animals dying from preoptic lung edema were significantly less than normal.

Acid phosphatase, alkaline phosphatase, and nitrate reductase activity of selected ectomycorrhizal fungi

1989 ◽  
Vol 67 (3) ◽  
pp. 750-753 ◽  
Author(s):  
Iwan Ho
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Nitrate Reductase ◽  
Phosphatase Activity ◽  
Ectomycorrhizal Fungi ◽  
Acid Phosphatase Activity ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Phosphatase Alkaline

Seventeen isolates, encompassing five genera and eight species of ectomycorrhizal fungi, were compared for acid phosphatase, alkaline phosphatase, and nitrate reductase activity. Isolates within species differed in enzyme activity and isozyme patterns by host specificity and site (as exemplified by the genus Suillus). Host and site may have affected phosphatase enzyme activity. Generally, the Douglas-fir associates, which dominate in mesic sites, have higher acid phosphatase activity than pine associates, which mostly occupy xeric sites; however, pine associates from mesic sites also have higher acid phosphatase activity (e.g., S. tomentosus). In four isolates of Amanita muscaria, the effect of site was also apparent. Two of them, which have significantly higher acid phosphatase activity than the others, were isolated from mesic sites. The isozyme pattern of the genus Suillus appeared to be separated by host groups. Other isolates with only one species also differed more or less by host groups. They shared at least one band within host groups, except for the two isolates of Paxillus involutus from different hosts. The P. involutus S-403 isolated from an orchard showed much higher nitrate reductase activity than all other isolates. No apparent differences in nitrate reductase activity were found between the other isolates.

scholarly journals Digestible methionine+cystine levels for white-egg layers aged one to six weeks

2020 ◽  
Vol 9 (8) ◽  
pp. e74985242
Author(s):  
Jalceyr Pessoa Figueiredo Junior ◽  
Fernando Guilherme Perazzo Costa ◽  
Ricardo Romão Guerra ◽  
Marcelo Helder Medeiros Santana ◽  
Matheus Ramalho de Lima ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Weight Gain ◽  
Liver Weight ◽  
Experimental Unit ◽  
Nutritional Requirements ◽  
Hepatic Glycogen ◽  
Gamma Glutamyl Transferase ◽  
Feed Conversion ◽  
Histological Data ◽  
Glutamyl Transferase

The aim of this study was was to determine the nutritional requirements of digestible methionine+cystine (M+C) for white-egg layers aged one to six weeks. A completely randomized design with five methionine+cystine levels, six replicates, and 30 birds per experimental unit was adopted. Dietary treatments consisted of five diets supplemented with DL-Methionine with resulted in five levels of digestible methionine + cystine, 80% (0.516%), 90% (0.578%), 100% (0.640%), 110% (0.702%), and 120% (0.764%), based on Brazilian tables of nutritional requirements. Performance, serological blood, and histological data were evaluated. Feed intake, feed conversion, hepatic glycogen deposition, enzymatic activity of alanine aminotransferase and gamma-glutamyl transferase, and serum creatinine and albumin levels had showed a quadratic response to the levels of digestible M+C, with the respective requirements: 89.78% (0.575%), 114.33% (0.732%), 86.50% (0.554%), 100% (0.640%), 100.40% (0.643%), 104.30% (0.668%), and 111.88% (0.716%). Increasing levels of methionine+cystine elevated the relative liver weight and the deposition of hepatic glycogen, in addition to promote higher growth in pullets, with better body weight and body weight gain and feed conversion ratio. Our findings suggest that 0.732% digestible methionine+cystine is recommended, which corresponds to an intake of 151.20 mg/bird/d and a Met+Cys:Lys  ratio 83%, for light pullets from one to six weeks.

scholarly journals Oleuropein alleviates gestational diabetes mellitus by activating AMPK signaling

2020 ◽  
Author(s):  
Zhiwei Zhang ◽  
Hui Zhao ◽  
Aixia Wang
Keyword(s):  
Oxidative Stress ◽  
Diabetes Mellitus ◽  
Body Weight ◽  
Blood Glucose ◽  
Gestational Diabetes ◽  
Gestational Diabetes Mellitus ◽  
Signaling Pathway ◽  
Hepatic Glycogen ◽  
Ampk Signaling ◽  
Tnf Α

Background: Gestational diabetes mellitus (GDM) has a high incidence rate among pregnant women. The objective of the study was to assess the effect of plant-derived oleuropein in attenuating inflammatory and oxidative stress of GDM. Methods: Oleuropein was administered to GDM mice at the doses of 5 or 10 mg/kg/day. Body weight, blood glucose, insulin and hepatic glycogen levels were recorded. To evaluate the effect of oleuropein in reducing oxidative stress, enzyme-linked immunosorbent assay (ELISA) was used to measure the hepatic oxidative stress markers. The inflammation levels of GDM mice were evaluated by measuring serum levels of IL-6 and TNF-α by ELISA, and mRNA levels of IL-1β, TNF-α and IL-6 by real-time PCR (RT-PCR). The AMP-activated protein kinase (AMPK) signaling pathway was assessed by Western blot. Gestational outcome was analyzed through comparing litter size and birth weight. Results: Oleuropein attenuated the elevated body weight of GDM mice, and efficiently reduced blood glucose, insulin and hepatic glycogen levels. Oxidative stress and inflammation were alleviated by oleuropein treatment. The AMPK signaling was activated by oleuropein in GDM mice. Gestational outcome was markedly improved by oleuropein treatment. Conclusions: Our study suggests that oleuropein is effective in alleviating symptoms of GDM and improving gestational outcome in the mouse model. This effect is achieved by attenuating oxidative stress and inflammation, which is mediated by the activation of the AMPK signaling pathway.

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