Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.9 (glucose-6-phosphatase)
 3,081 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A concomitant increase in the activity of LH-senstive adenylate cyclase and in the number of LH/hCG binding sites was induced in ovaries of immature rats upon administration of pregnant mare serum gonadotropin (PMSG), a hormone preparation known to have predominantly follicle stimulation (FSH-like) activity. When an optimal dose of PMSG (15 i.u./rat) was administered to 25-day-old rats, specific activity of LH-dependent adenylate cyclase and the number of binding sites for LH/hCG per mg protein remained unchanged during the first 24h, but 48h after injection a 2-to 4-fold increase in both parameters was observed. By contrast, there was no change in basal adenylate cyclase activity or in the response of the enzyme to the stimulatory action of guanosine-5'-(beta gamma-imino) triphosphate (Gpp (NH)p), GTP, or NaF. Specific activity of succinate cytochrome c reductase, glucose-6-phosphatase and 5'-nucleotidase were found to be unaffected by the hormonal pretreatment, although total protein determined in these homogenates increased 3-fold in the course of this treatment. It is inferred that during follicular maturation, FSH enhances the responsiveness of ovarian adenylate cyclase to LH by stimulating the insertion of LH/hCG-receptors into the cell membrane.
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PMID:Synchronous generation of ovarian hCG binding sites and LH-sensitive adenylate cyclase in immature rats following treatment with pregnant mare serum gonadotropin. 19 42

Glucose-6-phosphatase is generally accepted as a functional component of rough endoplasmic reticulum and has been histochemically examined in many organs. The aim of this study is to know the ultracytochemical localization of glucose-6-phosphatase in each type of hormone-producing cell constituting the anterior pituitary gland in the rat. Pituitaries of male Sprague-Dawley rats were perfused with 1.5% glutaraldehyde from the left ventricles. After buffer washing 40 microns sections were incubated in the medium of Hugon et al. for 60 min at 37 degrees C. The sections were then postfixed with 1% osmium tetroxide, embedded in epoxy resin and observed under an electron microscope. The reaction product for glucose-6-phosphatase was observed in the lumen of rough endoplasmic reticulum and nuclear envelope of all anterior pituitary cells. The enzyme activities in thyroid-stimulating hormone-producing cells and luteinizing hormone/follicle-stimulating hormone-producing cells (LH/FSH cells) were stronger than those in growth hormone-producing cells and prolactin-producing cells; adrenocorticotropic hormone-producing cells and folliculo-stellate cells presented intermediate activity. In LH/FSH cells, the activity in dilated cisternae of endoplasmic reticulum had weaker density than that in flattened cisternae. In addition, substantial reaction product was also frequently observed in the cis saccules of the Golgi apparatus. These findings suggest that glucose-6-phosphatase may play different functional roles in hormone synthesis within different types of anterior pituitary cells.
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PMID:Ultracytochemical localization of glucose-6-phosphatase in the rat anterior pituitary cells. 980 Mar 74