Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Luliberin, a luteinizing hormone-releasing hormone, was shown to inhibit the respiratory enzymes of rat liver mitochondria and submitochondrial particles prepared from beef heart mitochondria. At the hormone concentration of 8.10(-6) M the NADH-oxidase activity of the submitochondrial particles was inhibited by 50%. The fragments of the hormone and its analogs and pyroglutamic acid, oxytocin and bradikinin possessed practically no inhibiting effects. In the case of submitochondrial particles the inhibition was only observed in the presence of Ca2+ and was significantly decreased after addition of bovine serum albumin and phospholipase inhibitors -- butacaine and dicaine. It is assumed that the effect of luliberin on the respiratory chain is mediated through mitochondrial phospholipase.
 ...
PMID:[Effect of luliberin on the activities of mitochondrial respiratory enzymes]. 38 96

Sheep corpus luteum homogenates were fractionated by centrifugation on continuous sucrose density gradients, with or without digitonin, and gradient fractions were assayed for progesterone, and for a range of intracellular organelle and plasma-membrane markers. Digitonin had little effect on the density distributions of mitochondrial, rough endoplasmic reticulum (RER) and Golgi-endoplasmic reticulum-lysosomal (GERL) membranes. However, digitonin did disrupt lysosomal membranes, leading to release of acid hydrolases, and induced a decrease in buoyant density of NADH-cytochrome c reductase, a putative smooth endoplasmic reticulum (SER) marker. Oxytocin-containing granules were clearly resolved from other organelles accumulating in a sharp peak (density, 1.20 g/cm3). Luteal cell-surface membrane marker activities equilibrated at similar buoyant densities in control gradients, and pretreatment with digitonin induced a marked increase in their buoyant densities. The majority of the progesterone of the sheep corpus luteum equilibrated at a buoyant density of 1.10 g/cm3 in control gradients, and was highly perturbed by digitonin. These fractions also accumulated [3H]progesterone. The buoyant density profile of progesterone in both control and digitonin-treated gradients most closely resembled that of sheep luteal lactogenic receptor, a putative plasma-membrane marker.
 ...
PMID:Subcellular fractionation of the ovine corpus luteum: association of progesterone with ovine luteal membranes? 319 18

In the present study the fine structure of rat Leydig cells was examined by electron microscopy. Oxytocin and dexamethasone induced changes in the activities of 3beta hydroxysteroid dehydrogenase, NADH2 cytochrome-C-reductase and glucose-6-phosphate dehydrogenase in these cells were studied in an in vivo experiment. Two groups of male Wistar rats were used to test the effects of oxytocin--rats from group I received a single injection of oxytocin; rats from group II were given a 10-day course of oxytocin. Pregnant female rats were injected with dexamethasone on day 17 and 18 post conception. The testes of 19 and 20-day old embryos were removed. It was established that both short and long term courses of oxytocin increased the activities of the above-mentioned enzymes. On the contrary, prenatal administration of dexamethasone decreased enzymatic activity in Leydig cells. Electron microscopy revealed clusters of fetal Leydig cells. Our results indicated the role of oxytocin in the local regulation of steroidogenesis and the importance of glucocorticoids in the differentiation and activity of Leydig cells.
 ...
PMID:Dexamethasone and oxytocin effects on rat Leydig cells--morphological and enzyme-histochemical characteristics. 1258 May 30