Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lutropin (LH) receptors in rat granulosa cells are expressed by activation of cAMP-dependent protein kinase in response to follitropin (FSH). In the present study, 12-O-tetradecanoylphorbol 13-acetate (TPA) could cause a dose-dependent expression of LH receptors in the presence of insulin, but not in the absence of insulin, as measured by binding of 125I-deglycosylated human choriogonadotropin (DGhCG). The synergistic action of TPA with insulin was achieved at 1 nM and 10 mIU/ml, respectively. The receptor expression induced by this synergistic action was accompanied by cAMP accumulation which was detected after a lag time of 6 h following exposure to TPA. However, a synthetic diacylglycerol and non-protein kinase C activating phorbol derivatives did not mimic the effect of TPA on the receptor expression. In addition, insulin modulated the inhibitory effect of TPA in FSH-induced LH receptor expression, indicating a peculiar action of insulin in the receptor expression. Indomethacin treatment led to a dose-dependent inhibition in the receptor expression in the cells treated with TPA plus insulin more than that in the cells with FSH plus insulin, suggesting that the synergistic action was dependent upon cyclooxygenase and/or phospholipase A2 activity. It was shown by Scatchard analysis of LH receptors and kinetic studies of hCG-stimulated cAMP formation that the synergistic action of TPA with insulin led to expression of functional LH receptors coupled with the adenylate cyclase system in cultured granulosa cells.
Mol Cell Endocrinol 1991 Oct
PMID:Tumor-promoting phorbol ester acts synergistically with insulin to induce lutropin receptor expression in rat granulosa cells. 166 32

We examined bradykinin-induced 45Ca2+ efflux and prostaglandin synthesis in guinea pig tracheal smooth muscle cells maintained in tissue culture. We also studied the effects of a B1 receptor agonist and antagonist, a B2 receptor antagonist, and the cyclooxygenase inhibitor indomethacin. In cultured smooth muscle cells, bradykinin (0.1 nM to 10 microM) stimulated efflux of 45Ca2+ and induced the synthesis of prostaglandin E2 and the prostacyclin metabolite 6-keto-prostaglandin F1 alpha. DesArg9-bradykinin, a B1 receptor agonist, had no effect on 45Ca2+ efflux or prostaglandin synthesis, and no responses to bradykinin were unaffected by the B1 receptor antagonist desArg9-[Leu8]-bradykinin. Indomethacin (1 microM) abolished bradykinin-induced prostaglandin synthesis but was without effect on 45Ca2+ efflux. NPC 567 (DArg[Hyp3,DPhe7]-bradykinin), a B2 receptor antagonist, had no effect on bradykinin-induced 45Ca2+ efflux, but abolished prostaglandin synthesis. Unlike in membranes prepared freshly from guinea pig tracheal smooth muscle, the B2 receptor antagonist inhibited completely (Ki, 12 nM) binding of [3H]-bradykinin to membranes prepared from cultured tracheal smooth cells. These data suggest that tracheal smooth muscle cells, maintained in culture, express B2 receptors that mediate bradykinin-induced prostaglandin synthesis. The observation that bradykinin-induced efflux of calcium ions was unaffected by B1 or B2 antagonists provides further evidence that airway smooth muscle may contain a novel B3 receptor.
Am J Respir Cell Mol Biol 1991 Mar
PMID:Evidence that cultured airway smooth muscle cells contain bradykinin B2 and B3 receptors. 184 87

Isolated rat pancreatic islets prelabeled with myo-[3H]inositol respond to glucose and carbamylcholine with increased [3H] inositol phosphate (InsP) production. Prostaglandin E2 (PGE2) inhibits the effects of glucose and carbamylcholine on [3H]InsP production. Ionomycin reversed the effect of PGE2 on glucose-stimulated [3H]InsP production. The cyclooxygenase inhibitors indomethacin, ibuprofen, and eicosatetraynoic acid potentiated [3H]InsP production in response to 5 and 10 mM glucose but not to 17 mM glucose. Indomethacin did not affect the carbamylcholine response. Unsaturated fatty acids, including arachidonic acid, linolenic acid, eicosapentaenoic acid, oleic acid, and eicosatetraynoic acid, increased [3H]InsP production. Arachidonic acid potentiated [3H]InsP accumulation in response to low concentrations of glucose. Indomethacin potentiated the response to arachidonic acid. delta 9-Tetrahydrocannabinol, which mobilizes endogenous fatty acids, also potentiated glucose-stimulated [3H]InsP production. The lipoxygenase inhibitors BW755C and nordihydroguaiaretic acid inhibited [3H]InsP production in response to glucose, carbamylcholine, and fatty acids. Thus, PGE2 and endogenous cyclooxygenase products antagonize InsP production in islets, whereas fatty acids promote InsP accumulation.
Mol Pharmacol 1990 Jun
PMID:Fatty acids and cyclooxygenase and lipoxygenase pathway inhibitors modulate inositol phosphate formation in pancreatic islets. 211 5

Leishmania donovani is an obligate intracellular protozoan which resides in macrophages and impairs a number of macrophage functions. We have undertaken to study this host cell-parasite interaction by examining the ability of L. donovani to impair the transmission of information from the cell surface to the nucleus and thus influence normal gene expression. We demonstrate that, in response to lipopolysaccharide, expression of both the c-fos and tumor necrosis factor genes was impaired in L. donovani-infected macrophages. Indomethacin reversed the parasite-mediated downregulation of the tumor necrosis factor gene but not the c-fos gene, suggesting that the impaired expression of these two genes occurred through different mechanisms. Direct stimulation of protein kinase C with oleoyl-2-acetoyl-3-glycerol did not abrogate inhibition of c-fos gene expression by L. donovani; however, L929 cell-conditioned medium induced a similar level of c-fos gene expression in both infected and noninfected macrophages. Impairment of c-fos gene expression by L. donovani thus appeared to be selective, depending on the external stimuli used to induce its expression. These data argue that L. donovani was capable of impairing macrophage gene expression in a selective rather than a general manner.
Mol Cell Biol 1989 Nov
PMID:c-fos and tumor necrosis factor gene expression in Leishmania donovani-infected macrophages. 251 83

Phospholipase A2 (PLA2) produced slow dose dependent relaxation in intact and endothelium-deprived precontracted rabbit aortic strips. In endothelium-deprived preparations, relaxation induced by PLA2 is inhibited by hemoglobin, methylene blue and parabromophenacylbromide (PBPB), and is potentiated by superoxide dismutase (SOD). Indomethacin has no effect. Relaxation is accompanied by a rise in c-GMP. Phospholipase C causes a significant increase in tension, while Phospholipase D has no effects. In intact aortic strips PLA2 causes a biphasic response with no elevation in c-GMP. The results indicate several common features of the PLA2 released factor with endothelium-derived relaxing factor (EDRF). However, PLA2 induced relaxation is not dependent on endothelial cells. Apparently in addition to nitric oxide which may be the endothelium-derived relaxing factor, a second smooth muscle relaxing factor exists which is initiated by PLA2 and is independent of endothelium. The production of the PLA2 produced relaxation is dependent on its specific hydrolytic activity. We call this relaxing factor the phospholipid-derived relaxing factor (PDRF).
Mol Cell Biochem 1987 Nov
PMID:A relaxing factor released by phospholipase A2 in the absence of endothelium. 284 57

Experiments with primary cultures of isolated porcine thyroid follicles were performed in serum-free well-defined medium to investigate different pathways that may be involved in the regulation of thyroid cell growth. The incorporation of [3H]thymidine into DNA within 72 h was about 25-fold with fetal calf serum (FCS, 1%), 20-fold with epidermal growth factor (EGF, 1 ng/ml) and 3.5-fold with insulin (10 micrograms/ml) as compared to controls. Bovine TSH significantly reduced the basal and insulin-induced growth rate at concentrations of 10(-6) to 10(-4) U/ml and 10(-4) U/ml, respectively. Forskolin stimulated cyclic AMP accumulation in thyroid cells and significantly reduced FCS-, EGF- or insulin-induced growth. In contrast, a 2- to 7-fold increase in FCS-, insulin- or EGF-induced growth rate was found, when cyclic AMP formation was inhibited by 2',5'-dideoxyadenosine (DDA). Iodide was stimulatory at low concentrations (1 microM) and inhibitory at higher concentrations (40-80 microM) on FCS-induced growth rate. The inhibitory effect of iodide was blocked by propylthiouracil (PTU), indicating that an iodinated compound is responsible for this effect. Indomethacin, a cyclooxygenase inhibitor, did not inhibit EGF- and insulin-induced growth up to a concentration of 100 microM. However, nordihydroguaiaretic acid (NDGA) and BW-755C, which are lipoxygenase inhibitors, strongly inhibited the growth of thyroid cells at micromolar concentrations. These data clearly show that (1) bovine TSH is not a growth factor for isolated thyroid cells in vitro, (2) thyroid cell proliferation, induced by FCS, EGF and insulin is under negative control of cyclic AMP. (3) Iodide controls dose-dependently thyroid cell growth by iodinated metabolites, probably modulating 2 different pathways: (a) at low iodide concentrations, an iodinated compound enhances the growth rate by inhibition of cyclic AMP formation, and (b) at high concentrations, iodide diminishes the growth rate by inhibiting the response to growth factors. (4) Metabolite(s) of lipoxygenase appear to be involved in intracellular signal transduction evoked by growth factors in thyroid cells.
Mol Cell Endocrinol 1985 Sep
PMID:Involvement of cyclic AMP, iodide and metabolites of arachidonic acid in the regulation of cell proliferation of isolated porcine thyroid follicles. 299 5

The effects of agents that cause vasodilatation and hypotension, such as endogenously produced bradykinin (BK) or the drug nitroprusside (NP), appear to result from effects on cyclic nucleotides (cGMP, cAMP) and arachidonate metabolism. Cultured human fibroblasts, which possess B2 BK receptors and respond to NP with an increase in cGMP, were used to study the interaction of these agents at the molecular level. Addition of BK or NP to cultured human fibroblasts caused a rapid increase in cGMP. The effect of NP was usually maximal within 30 sec, after which cGMP content declined. The increase in cGMP produced by BK reached a maximum at approximately 1 min and then fell; the rise with NP was more than 10 times that with BK. At 30 sec, cGMP content with NP plus BK was less than with NP alone. At later times, however, effects of BK and NP were slightly more than additive and maximal cGMP levels were reached at 90 sec. BK increased prostaglandin production by the fibroblasts; it is believed that the kinin-induced elevation in cAMP content is secondary to increased prostaglandin formation. NP caused a small, early increase in cAMP without significant effect on prostaglandin I2 (PGI2); after 2.5 min, effects on PGI2 and cAMP were greater with BK and NP than with BK alone. To study further the roles of arachidonate metabolites in the fibroblast response to BK and NP, the cyclooxygenase inhibitor, indomethacin, and the combined lipoxygenase and cyclooxygenase inhibitor, 5,8,11,14-eicosatetraynoic acid (ETYA), were added to fibroblasts prior to BK or NP. Increases in cAMP or PGI2 with BK or BK plus NP were blocked by indomethacin or ETYA. These effects of BK or BK plus NP on cAMP thus appear to be mediated through cyclooxygenase products of arachidonate metabolism. Indomethacin and ETYA did not affect cGMP in the presence of BK plus NP but enhanced NP-stimulated cGMP accumulation by 40-50%; effects of NP on cGMP may be independent of or perhaps inhibited by cyclooxygenase derivatives. Cellular responses to BK plus NP differed quantitatively and temporally from the sum of effects of BK and NP alone. Through interactions of this type, in vivo responses to drugs like NP may be influenced by levels of BK or similar endogenous mediators.
Mol Pharmacol 1986 Sep
PMID:Effects of nitroprusside on the bradykinin responsiveness of human fibroblasts. 301 83

Human granulosa-luteal cell production of cyclic adenosine 3', 5'-monophosphate (cAMP) and progesterone (P) were studied in response to 12-O-tetradecanoyl-phorbol-13-acetate (TPA). TPA specifically increased cAMP synthesis in a dose-dependent manner. A 7-fold increase occurred at a TPA concentration of 1 ng/ml. Time-course studies indicated that the increase in accumulation of cAMP into culture media became detectable at 4 h and continued up to 72 h. TPA also enhanced P synthesis, but the increase was statistically significant only at 72 h. Indomethacin prevented TPA-stimulated cAMP and P production. The results suggest that TPA stimulates granulosa-luteal cell cAMP and P production, and that the action of TPA is mediated by the increase in prostaglandin synthesis.
Mol Cell Endocrinol 1987 Jun
PMID:Phorbol ester stimulates human granulosa-luteal cell cyclic adenosine 3', 5'-monophosphate and progesterone production. 303 28

We have investigated the involvement of arachidonic acid release and metabolism in the mitogenic response, i.e., [3H]thymidine incorporation, to epidermal growth factor (EGF) in BALB/c 3T3 cells. EGF induces release of arachidonate and prostaglandin (PG) formation after its addition to BALB/c 3T3 cells at the same concentrations that stimulate mitogenesis. Further, EGF-stimulated mitogenesis is blocked by inhibitors of arachidonate metabolism including indomethacin, eicosatetraynoic acid, and dexamethasone, whereas the addition of major arachidonate products in BALB/c 3T3 cells, PGE2, PGF2 alpha, and their intermediates PGG2 and PGH2, stimulate mitogenesis in synergism with EGF. The addition of PGs to BALB/c 3T3 cells also overcame indomethacin- and eicosatetraynoic acid-inhibited responses to EGF. Indomethacin must be added with EGF in order to block arachidonate metabolism and subsequent mitogenesis. These results suggest that the release of arachidonic acid and its subsequent metabolism is an apparent early requirement for the initiation of cell cycle traversal by EGF.
Mol Pharmacol 1988 Jun
PMID:Role of arachidonic acid metabolism in the mitogenic response of BALB/c 3T3 fibroblasts to epidermal growth factor. 313 9

In androgenized-hypophysectomized rats, ovine prolactin stimulated the activity of the ornithine decarboxylase (ODC) of the lateral lobes, but not the ventral and dorsal lobes of the prostate glands in a time- and dose-dependent fashion. High degrees of enzyme stimulation were associated with significant elevations in the endogenous levels of its product, putrescine. The relative response to prolactin over basal activities was relatively unaffected by indomethacin but decreased with cycloheximide, suggesting that prostaglandins do not mediate the effects of the hormone, but that a high rate of protein synthesis is a prerequisite for its expression. Indomethacin alone significantly increased the basal activity of the enzyme above control levels, suggesting that prostaglandins may normally exert a degree of inhibition on the ODC. The selective activation of the lateral lobe ODC supports previous reports of a differential response of the various prostatic lobes to prolactin, and also provides a convenient biochemical response for examining details of prolactin action on this organ.
Mol Cell Endocrinol 1987 Mar
PMID:Prolactin selectively stimulates ornithine decarboxylase in the lateral lobe of the rat prostate. 358 28


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