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Query: UNIPROT:P20366 (
substance P
)
21,176
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In this study, we have compared the effects of
Substance P
(SP) and an SP deprived of the N-terminal tripeptide, SP(4-11), on phosphoinositide metabolism by measuring phosphoinositide breakdown, inositol phosphate production and inositol incorporation into phosphoinositides. This work shows that SP and SP(4-11) have similar effects on phosphatidylinositol-4.5 bisphosphate (PIP2) metabolism. In fact, SP(4-11), like SP, induces a rapid PIP2 breakdown. On the contrary, SP and SP(4-11) have different effects on phosphatidylinositol (PI) metabolism since SP induces a decrease of radioactivity in PI, whereas SP(4-11) does not. Both peptides stimulate [3H]-inositol mono-, bis- and trisphosphate (respectively IP1, IP2, IP3) production in a time and dose-dependent manner. The kinetic of IP3 production is directly correlated with the one of PIP2 breakdown. The time course of IP1 production after SP(4-11) shows a time delay, while the one after SP does not. Since SP evokes an IP1 production without any delay and a large decrease of radioactivity in PI (which cannot account for the small amount measured in IP1 accumulation) we suggest that SP could activate a PI specific phospholipase C (leading to a PI breakdown) and a
phospholipase D
. These activations would require the complete structure of SP while the classical PIP2 specific phospholipase C activation (which induces PIP2 breakdown) would only require the carboxamide part of the peptide. So the complete structure of SP would be necessary to have a complete response (stimulation of PIP2 and PI metabolism).
...
PMID:Importance of the presence of the N-terminal tripeptide of substance P for the stimulation of phosphatidylinositol metabolism in rat parotid gland: a possible activation of phospholipases C and D. 246 32
Substance P
(SP) is a
tachykinin
involved in the regulation of inflammatory processes. Tachykinins bind to three subtypes of neurokinin (NK) receptors. However, recently we demonstrated that monocytes express a SP binding site that is not one of the known NK receptors. Activation of this SP receptor leads to the stimulation of MAP kinase in monocytes. In the present paper we show that this novel SP binding site is coupled to a GTP binding protein of the Gi alpha 1/2 subclass. Triggering of the SP receptor leads to a rapid rise in cytosolic calcium. In a more sustained way, SP stimulates
phospholipase D
(PLD) activity in human monocytes. The effects of SP on calcium, PLD, and MAP kinase activity can be blocked by pretreatment of the cells with pertussis toxin, which is in agreement with receptor coupling to Gi. At a functional level, stimulation of the non-NK SP receptor on monocytes results in the induction of IL-6 production. We show here that the order of potency for activation of monocytes by various ligands is directly related to the Ki for displacement of labeled SP by these ligands. Therefore, our data strongly suggest that the effects of SP are mediated via the novel SP receptor we recently described.
...
PMID:Activation of human monocytes via a non-neurokinin substance P receptor that is coupled to Gi protein, calcium, phospholipase D, MAP kinase, and IL-6 production. 793 May 88
Endothelins (ETs) were initially thought to be primarily involved in the control of cardiovascular activity, but the presence of ETs and their receptors in a wide variety of other tissues has suggested a much broader range of functions. Specific receptors for ETs are found in nonvascular tissues including neuronal, neuroendocrine, and endocrine cells. In addition, immunoreactive ETs are present in the brain, pituitary, and peripheral endocrine tissues. However, the ET levels in hypothalamo-hypophysial portal and peripheral blood are low, suggesting that the ET system participates in neuroendocrine regulation through paracrine and/or autocrine mechanisms. Both ETA and ETB receptors are expressed in the hypothalamus, adrenal, parathyroid glands, pancreas, ovary, uterus, placenta, and prostate, while only ETA receptors are expressed in GT1 neurons, anterior pituitary cells, alpha T3-1 immortalized gonadotropes, parathyroid-derived cells, thyrocytes, testicular Leydig and Sertoli cells, normal and neoplastic ovarian granulosa cells, chondrocytes, and other cell types. Activation of ET receptors elicits the sequence of cellular events typical of Ca(2+)-mobilizing receptors, with prominent increases in phosphoinositide hydrolysis and elevations of [Ca2+]i that occur in oscillatory and nonoscillatory modes depending on the cell type. ET-induced activation of the phosphoinositide/Ca(2+)- mobilizing pathway in neuronal and endocrine cells is associated with rapid stimulation of secretory responses, including release of gonadotropin-releasing hormone, oxytocin, vasopressin,
substance P
, atrial natriuretic peptides, gonadotropins, thyrotropin, growth hormone, parathyroid hormone, aldosterone, and catecholamines. On the other hand, ET has inhibitory actions on prolactin, progesterone, and renin release. In addition to stimulating phospholipase C-dependent pathways, ETs also activate
phospholipase D
-and MAP-kinase-dependent pathways in some of their target cells, as well as expression of early response genes and increased mitogenic activity. In many neuroendocrine cells, ET induces rapid and marked desensitization of its signaling system, in association with extensive internalization of ET receptors and reduced signaling and secretory responses. These findings raise the possibility that ETs participate in the control of secretory responses in the hypothalamo-pituitary system and peripheral endocrine cells, as well as in long-term aspects of regulation in certain neuroendocrine cells.
...
PMID:Expression and signal transduction pathways of endothelin receptors in neuroendocrine cells. 881 99
Secretoneurin (SN), a 33-amino acid neuropeptide, is derived from secretogranin II that is released from sensory afferent C-fibers by capsaicin. Described functions of secretoneurin include chemotaxis of monocytes and endothelial cells, and inhibition of endothelial cell proliferation. Inhibition of monocyte chemotaxis by staurosporine indicated involvement of specific signaling pathways. We have tested effects of SN,
substance P
(SP), and interleukin-8 (IL-8) on eosinophil migration in modified Boyden chambers including signaling mechanisms of neuropeptide and cytokine stimulation of human eosinophils. Experiments showed SN as eosinophil chemoattractant comparable in its potency to IL-8. Checkerboard analysis, usage of a specific anti-SN-antibody, and receptor desensitization experiments confirmed the chemotactic activity. Preincubation of the cells with effective concentrations of staurosporine or tyrphostin-23 showed no effect, whereas treatment with wortmannin (WTN) or 3-isobutyl-1-methylxantin (IBMX) completely blocked SN-induced migration. Additionally, experiments ruled out tyrphostin-23- and WTN-sensitive signaling pathways for SP-induced chemotaxis of eosinophils. We conclude that SN-stimulated human eosinophil chemotaxis is mediated via a unique and specific signal transduction pathway that involves activation of phosphodiesterases and WTN-sensitive enzymes, ie,
phospholipase D
and phosphatidylinositol-3-kinase. In contrast, we report that activation of the latter and tyrosine kinases is required for SP-induced chemotaxis of eosinophils.
...
PMID:Secretoneurin, a novel neuropeptide, is a potent chemoattractant for human eosinophils. 947 16
In [3H]myristic acid-prelabeled Chinese hamster ovary cells stably expressing the rat NK1
tachykinin
receptor, the selective NK1 agonist [Pro9]
substance P
([Pro9]SP) time and concentration dependently stimulated the formation of [3H]phosphatidylethanol in the presence of ethanol. This [Pro9]SP-induced activation of
phospholipase D
(PLD) was blocked by NK1 receptor antagonists and poorly or not mimicked by NK2 and NK3 agonists, respectively. In confirmation of previous observations, [Pro9]SP also stimulated the hydrolysis of phosphoinositides, the release of arachidonic acid, and the formation of cyclic AMP (cAMP). All these [Pro9]SP-evoked responses could be mimicked by aluminum fluoride, but they remained unaffected in cells pretreated with pertussis toxin, suggesting that a Gi/Go protein is not involved in these different signaling pathways. The activation of PLD by [Pro9]SP was sensitive to external calcium and required an active protein kinase C because the inhibition of this kinase (Ro 31-8220) or its down-regulation (long-term treatment with a phorbol ester) abolished the response. In contrast, a cAMP-dependent process was not involved in the activation of PLD because the [Pro9]SP-evoked response was neither affected by Rp-8-bromoadenosine 3',5'-cyclic monophosphorothioate nor mimicked by cAMP-generating compounds (cholera toxin or forskolin) or by 8-bromo-cyclic AMP. A functional coupling of NK1 receptors to PLD was also demonstrated in the human astrocytoma cell line U 373 MG stimulated by SP or [Pro9]SP. These results suggest that PLD activation could be an additional signaling pathway involved in the mechanism of action of SP in target cells expressing NK1 receptors.
...
PMID:Functional coupling of the NK1 tachykinin receptor to phospholipase D in chinese hamster ovary cells and astrocytoma cells. 957 95