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)

The aims of this study were to investigate if administration of oxytocin to ad libitum fed and food-restricted female rats affects weight gain, body fatness, the IGF-axis, and some vagally mediated gastrointestinal hormones, such as gastrin, cholecystokinin (CCK) and somatostatin. Ad libitum fed and food-restricted (receiving 70% of the food intake of the ad libitum fed group) female rats were injected subcutaneously, once a day, for 10 days, with saline (control) or oxytocin (1 mg kg-1 bodyweight). The animals were killed 5 days after the last injection. Oxytocin-treated food-restricted females had more body fat and lower plasma levels of IGF-I, IGFBP-1 and IGFBP-3 compared with saline-treated counterparts. Oxytocin-treated ad libitum fed rats also had lower plasma levels of IGFBP-1 but contained less body fat, compared with saline-treated counterparts. There was no effect of oxytocin treatment on body weight or weight gain in either of the feeding groups. Except for gastrin, which was lower, there was no effect of oxytocin on the gastrointestinal hormones studied. The results indicate that oxytocin treatment influences fat deposition and the IGF-axis in female rats, but that the results are dependent on the nutritional status of the animal.
 ...
PMID:Effects of oxytocin on the IGF-axis and some gastrointestinal hormones in ad libitum fed and food-restricted female rats. 1046 59

We have studied the action of GH on the production of hormones, growth factors, growth factor-binding protein and the occurrence of apoptosis in bovine ovarian granulosa cells, as well as the role of cAMP-stimulated protein kinase A (PKA) in the mediation of these effects. For this purpose we investigated the effects of exogenous bovine GH (0.001-10 microgram/ml), PKA blockers KT5720 (100 ng/ml) and adenosine-3',5'-monophosphothiodate (Rp-cAMPS) (1 micromol), alone and in combination, on IGF-I, IGF-binding protein (IGFBP)-3, oxytocin, progesterone and estradiol secretion, cAMP and PKA content and the occurrence of apoptosis. The secretion of hormones, IGF-I and IGFBP-3 into the culture medium was measured using RIA/IRMA. The presence of PKA was detected using immunocytochemistry and Western immunoblotting. The presence of cAMP in cells was demonstrated using immunocytochemistry, whilst the proportion of apoptotic cells was determined by the TUNEL method. It was found that the addition of GH to the culture medium strongly (P<0.05) stimulated IGF-I (at a concentration of 0.001-10 microgram GH/ml medium), IGFBP-3 (0.001-1 microgram GH/ml) and oxytocin (0.01-10 microgram GH/ml) secretion. Low concentrations (1-100 ng/ml) of GH stimulated, whilst a higher concentration (10 microgram/ml) inhibited estradiol output. GH slightly (P<0.05) inhibited progesterone (1-100 ng GH/ml) secretion and significantly (P<0.05) decreased the incidence of apoptosis (0.01-1 microgram GH/ml) in cultured cells. The addition of GH (100 ng/ml) caused a dramatic (P<0.05) increase in the proportion of cells possessing the immunoreactive catalytic subunit of PKA and a slight decrease in the proportion of cells containing the regulatory PKA subunit.PKA blockers KT5720 and Rp-cAMPS significantly (P<0.05) reduced the proportion of granulosa cells containing cAMP, and the catalytic and (in the case of KT5720) regulatory subunits of PKA. KT5720 given alone significantly (P<0.05) inhibited the secretion of IGFBP-3, but not that of IGF-I or progesterone. Rp-cAMPS decreased (P<0.05) the secretion of oxytocin but not that of estradiol output or the occurrence of apoptosis. KT5720 and Rp-cAMPS fully or partially prevented the GH effect on IGF-I, IGFBP-3, oxytocin, progesterone, estradiol and apoptosis. These observations suggest the involvement of GH and a cAMP/PKA-dependent intracellular cascade in the control of IGF-I, IGFBP-3, oxytocin, progesterone, estradiol, cAMP and apoptosis in bovine ovarian granulosa cells. The stimulation of PKA by GH and the prevention of GH-induced effects by PKA blockers suggest that the observed GH effects on bovine ovarian cells are probably mediated by the cAMP/PKA system.
 ...
PMID:GH regulates secretory activity and apoptosis in cultured bovine granulosa cells through the activation of the cAMP/protein kinase A system. 1055 82

The aim of our studies was to examine whether IGF-binding protein (IGFBP)-4 is involved in the control of the secretion of various ovarian substances and also the mediation of the effects of several hormones and growth factors on this secretion. For this purpose, we carried out the transfection of porcine granulosa cells with a cDNA sense construct, increasing IGFBP-4 synthesis. We then compared the release of IGFBP-3, progesterone, oxytocin and IGF-I by control and transfected cells cultured with and without porcine LH (100 ng/ml), porcine GH (100 ng/ml), IGF-I (10 ng/ml), oxytocin (10 ng/ml) and estradiol-17beta (100 ng/ml). The concentration of IGFBP-4 produced was assessed using ligand blotting, and the release of progesterone, oxytocin, IGF-I and IGFBP-3 was evaluated using RIA/IRMA techniques. It was observed that GH, IGF-I, estradiol, LH and oxytocin alter the progesterone, oxytocin, IGF-I and IGFBP-3 release by porcine ovarian granulosa cells. Transfection of these cells with an IBFBP-4 cDNA expression construct significantly increased the IGFBP-4 accumulation in cell-conditioned medium. Furthermore, this transfection significantly reduced progesterone, oxytocin and IGFBP-3 release, and increased IGF-I output in cells cultured in the absence or presence of GH, IGF-I, estradiol and LH. The addition of oxytocin, but not of other tested substances, fully or partially prevented the effects of IGFBP-4 overexpression on IGFBP-3, IGF-I, but not on progesterone release. The present results suggested that IGFBP-4, as well as GH, IGF-I, estradiol, LH and oxytocin, is a potent regulator of porcine ovarian steroid (progesterone), nonapeptide hormone (oxytocin), growth factor (IGF-I) and growth factor-binding protein (IGFBP-3) release. IGFBP-4 is an inhibitor of basal progesterone, oxytocin and IGFBP-3 release and a stimulator of IGF-I output by porcine ovarian cells. The action of IGFBP-4 on the ovary can be mediated by (1) inhibition of oxytocin release, (2) suppression of receptor/postreceptor events induced by other hormones and IGF-I and (3) stimulation of IGF-I release.
 ...
PMID:The transfection-induced overexpression of IGF-binding protein-4 affects the secretory activity of porcine ovarian granulosa cells and their response to hormones and IGF-I. 1135 60

The aim of our in vitro experiments was to examine if IGF binding protein (IGFBP)-3 is involved in control of bovine ovarian secretory activity. For this purpose we performed the transfection of bovine granulosa cells with cDNA sense and antisense constructs increasing or inhibiting IGFBP-3 synthesis. The release of IGFBP-3, progesterone, oxytocin, IGF-I and prostaglandins F (PGF) and E (PGE) by control and transfected cells was compared. The transfected ovarian cells were cultured with and without bLH (100 ng/ml), bGH (100 ng/ml), IGF-I (10 ng/ml), oxytocin (10 ng/ml) and oestradiol-17beta (100 ng/ml). The concentration of IGFBP-3 produced was assessed using ligand and western blotting and secretion of progesterone, oxytocin, IGF-I, PGF and PGE was evaluated using RIA/IRMA techniques. Transfection of cells with the sense IGFBP-3 cDNA construct resulted in the expected increase in IGFBP-3 release, whereas the antisense IGFBP-3 construct induced the expected reduction in IGFBP-3 output. The granulosa cells transfected to overexpress IGFBP-3 had an increase in IGF-I, PGF and PGE release, and a decrease in basal and hormone- or growth factor-induced accumulation of progesterone and oxytocin. The granulosa cells transfected to have reduced IGFBP-3 expression gave primarily significant opposite findings. The present results suggest the involvement of IGFBP-3 in control of bovine ovarian steroid, peptide hormone, growth factor and prostaglandin release. IGFBP-3 is a physiological stimulator of IGF-I and prostaglandin release and an inhibitor of steroid and peptide hormone output.
 ...
PMID:Secretory activity of bovine ovarian granulosa cells transfected with sense and antisense insulin-like growth factor (IGF) binding protein-3 and the response to IGF-I, GH, LH, oxytocin and oestradiol. 1171 85

The action of growth hormone (GH) on the production of hormones, growth factors, growth factor binding protein and the occurrence of apoptosis in porcine ovarian granulosa cells, as well as the role of cAMP-stimulated protein kinase A (PKA) in the mediation of these effects, were studied. For this purpose, the effects of exogenous pGH (1-10,000 ng/ml), PKA blockers KT5720 (100 ng/ml) and Rp-cAMPS (1micromol), alone and in combination, on insulin-like growth factor type I (IGF-I), insulin-like binding protein 3 (IGFBP-3), oxytocin (OT) and prostaglandin F alpha (PGF) secretion, PKA and cAMP response element binding transcription factor (CREB) content and the occurrence of apoptosis were investigated. It was found (using RIA/IRMA) that GH addition to culture medium significantly stimulated IGF-I and PGF release and inhibited IGFBP-3 and OT secretion. GH significantly decreased the incidence of apoptosis (TUNEL method) in cultured cells. Immunocytochemical study and Western immunoblotting showed, that addition of GH caused a dramatic increase in the accumulation of immunoreactive PKA within the cells, whilst Western blotting did not reveal marked influence of GH on content of CREB in cell lysates. PKA blockers, given alone, were able to decrease IGFBP-3 output (Rp-cAMPS, but not KT5720), reduce basal OT release (either Rp-cAMPS and KT5720) and increase PGF accumulation (KT5720, but not Rp-cAMPS). Furthermore, PKA blockers were able to prevent stimulatory effects of GH on IGF-I and PGF release, and inhibitory effect of GH on IGFBP-3, OT output and on apoptosis. These observations suggest the involvement of GH and a PKA-dependent intracellular mechanism in the control of IGF-I, IGFBP-3, OT, PGF, cAMP and apoptosis in porcine ovarian granulosa cells. Stimulation of PKA by GH and the prevention of GH-induced effects by PKA blockers suggest that both stimulatory and inhibitory effects of GH on porcine ovarian cells are probably mediated by the cAMP/PKA system.
 ...
PMID:Growth hormone can regulate functions of porcine ovarian granulosa cells through the cAMP/protein kinase A system. 1184 11