Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P20366 (substance P)
21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The beta-arrestins, a small family of G protein-coupled receptor (GPCR)-binding proteins involved in receptor desensitization, have been shown to bind extracellular signal-regulated kinases 1 and 2 (ERK1/2) and function as scaffolds for GPCR-stimulated ERK1/2 activation. To better understand the mechanism of beta-arrestin-mediated ERK1/2 activation, we compared ERK1/2 activation by the wild-type neurokinin 1 (NK1) receptor with a chimeric NK1 receptor having beta-arrestin1 fused to the receptor C terminus (NK1-betaArr1). The NK1 receptor couples to both G(s) and G(q/11), resides on the plasma membrane, and mediates rapid ERK1/2 activation and nuclear translocation in response to neurokinin A. In contrast, NK1-betaArr1 is a G protein-uncoupled "constitutively desensitized" receptor that resides almost entirely in an intracellular endosomal compartment. Despite its inability to respond to neurokinin A, we found that NK1-betaArr1 expression caused robust constitutive activation of cytosolic ERK1/2 and that endogenous Raf, MEK1/2, and ERK1/2 coprecipitated in a complex with NK1-betaArr1. While agonist-dependent ERK1/2 activation by the NK1 receptor was independent of protein kinase A (PKA) or PKC activity, NK1-betaArr1-mediated ERK1/2 activation was completely inhibited when basal PKA and PKC activity were blocked. In addition, the rate of ERK1/2 dephosphorylation was slowed in NK1-betaArr1-expressing cells, suggesting that beta-arrestin-bound ERK1/2 is protected from mitogen-activated protein kinase phosphatase activity. These data suggest that beta-arrestin binding to GPCRs nucleates the formation of a stable "signalsome" that functions as a passive scaffold for the ERK1/2 cascade while confining ERK1/2 activity to an extranuclear compartment.
...
PMID:Constitutive ERK1/2 activation by a chimeric neurokinin 1 receptor-beta-arrestin1 fusion protein. Probing the composition and function of the G protein-coupled receptor "signalsome". 1667 94

Specific functions of interstitial cells of Cajal (ICC) have been linked to distinct classes that differ by morphology and distribution. In the small intestine, slow wave-generating ICC are located in the myenteric region (ICC-MY), whereas ICC that mediate neuromuscular neurotransmission occur either throughout the circular muscle layer (intramuscular ICC, ICC-IM) or in association with the deep muscular plexus (ICC-DMP). Selective isolation of ICC to characterize specific properties has been difficult. Recently, neurokinin-1 receptors have been detected in murine ICC-DMP and neurons but not in ICC-MY. Here we identified and isolated ICC-DMP/IM by receptor-mediated internalization of fluorescent substance P and Kit immunofluorescence. Specificity of labeling was verified by confocal microscopy. Mouse and human ICC-DMP/IM were detected in suspension by fluorescent microscopy and harvested for RT-PCR with micropipettes. The isolated cells expressed Kit but not markers for neurons, smooth muscle, or antigen-presenting cells. ICC-DMP expressed neurokinin-1 receptor, M(2) and M(3) muscarinic receptors, P2Y(1) and P2Y(4) purinergic receptors, VIP receptor 2, soluble guanylate cyclase-1 subunits, and protein kinase G. L- or T-type Ca(2+) channels were not detected in these cells. ICC-MY and ICC-DMP were simultaneously detected and enumerated by flow cytometry and sorted to purity by fluorescence-activated cell sorting. In summary, functional classes of ICC have distinct molecular identities that can be used to selectively identify and harvest these cells with, for example, receptor-mediated uptake of substance P and Kit immunofluorescence. ICC-DMP express neurotransmitter receptors and signaling intermediate molecules that are consistent with their role in neuromuscular neurotransmission.
...
PMID:Selective labeling and isolation of functional classes of interstitial cells of Cajal of human and murine small intestine. 1694 45

Variability is increasingly recognized as a characteristic feature of cellular, synaptic, and network properties. While studies have traditionally focused on mean values, significant effects can result from changes in variance. This study has examined cellular and synaptic variability in the lamprey spinal cord and its modulation by the neuropeptide substance P. Cellular and synaptic variability differed in different types of cell and synapse. Substance P reduced the variability of subthreshold locomotor-related depolarizations and spiking in motor neurons during network activity. These effects were associated with a reduction in the variability of spiking in glutamatergic excitatory network interneurons and with a reduction in the variance of excitatory interneuron-evoked excitatory postsynaptic potentials (EPSPs). Substance P also reduced the variance of postsynpatic potentials (PSPs) from crossing inhibitory and excitatory interneurons, but it increased the variance of inhibitory postsynpatic potentials (IPSPs) from ipsilateral inhibitory interneurons. The effects on the variance of different PSPs could occur with or without changes in the PSP amplitude. The reduction in the variance of excitatory interneuron-evoked EPSPs was protein kinase A, calcium, and N-methyl-d-aspartate (NMDA) dependent. The NMDA dependence suggested that substance P was acting postsynaptically. This was supported by the reduced variability of postsynaptic responses to glutamate by substance P. However, ultrastructural analyses suggested that there may also be a presynaptic component to the modulation, because substance P reduced the variability of synaptic vesicle diameters in putative glutamatergic terminals. These results suggest that cellular and synaptic variability can be targeted for modulation, making it an additional source of spinal cord plasticity.
...
PMID:Modulation of cellular and synaptic variability in the lamprey spinal cord. 1702 Oct 27

The respiratory tract is innervated by irritant-responsive sensory nerves, which, on stimulation, release tachykinin neuropeptides in the lung. Tachykinins modulate inflammatory responses to injury by binding to tachykinin (neurokinin) receptors present on various pulmonary cell types. In the present study, the activation of the proinflammatory transcription factor NF-kappaB in lung epithelial cells was investigated as a mechanism by which tachykinins stimulate inflammatory processes. In A549 human lung epithelial cells transfected with the tachykinin-1 receptor (Tacr1), treatment with the Tacr1 ligand substance P (SP) resulted in NF-kappaB activation, as judged by transcription of an NF-kappaB-luciferase reporter gene and production of interleukin-8, a chemokine whose expression is upregulated by NF-kappaB. SP caused a dose-dependent activation of NF-kappaB that was inhibited by the selective Tacr1 antagonist RP67580. Tacr1 is a G protein-coupled receptor capable of activating both the G(q) and G(s) families of G proteins. Expression of inhibitory peptides and constitutively active G protein mutants revealed that G(q) signaling was both necessary for Tacr1-induced NF-kappaB activation and sufficient for NF-kappaB activation in the absence of any other treatment. Treatment with pharmacological inhibitors to investigate events downstream of G(q) revealed that Tacr1-induced NF-kappaB activation proceeded through an intracellular signaling pathway that was dependent on phospholipase C, calcium, Ras, Raf-1, MEK, Erk, and proteasome function. These results identify intracellular signaling mechanisms that underlie the proinflammatory effects of tachykinins, which previously have been implicated in lung injury and disease.
...
PMID:Tachykinin-1 receptor stimulates proinflammatory gene expression in lung epithelial cells through activation of NF-kappaB via a G(q)-dependent pathway. 1704 Oct 11

The neuropeptide substance P (SP) is expressed in unmyelinated primary sensory neurons and represents the best known "pain" neurotransmitter. It is generally believed that SP regulates pain transmission and sensitization by acting on neurokinin-1 receptor (NK-1), which is expressed in postsynaptic dorsal horn neurons. However, the expression and role of NK-1 in primary sensory neurons are not clearly characterized. Our data showed that NK-1 was expressed in both intact and dissociated dorsal root ganglion (DRG) neurons. In particular, NK-1 was mainly coexpressed with the capsaicin receptor TRPV1 (transient receptor potential vanilloid subtype 1), a critical receptor for the generation of heat hyperalgesia. NK-1 agonist [Sar(9), Met(O2)(11)]-substance P (Sar-SP) significantly potentiated capsaicin-induced currents and increase of [Ca2+]i in dissociated DRG neurons. NK-1 antagonist blocked not only the potentiation of TRPV1 currents but also heat hyperalgesia induced by intraplantar Sar-SP. NK-1 antagonist also inhibited capsaicin-induced spontaneous pain, and this inhibition was enhanced after inflammation. To analyze intracellular cross talking of NK-1 and TRPV1, we examined downstream signal pathways of G-protein-coupled NK-1 activation. Sar-SP-induced potentiation of TRPV1 was blocked by inhibition of G-protein, PLCbeta (phospholipase C-beta), or PKC but not by inhibition of PKA (protein kinase A). In particular, PKCepsilon inhibitor completely blocked both Sar-SP-induced TRPV1 potentiation and heat hyperalgesia. Sar-SP also induced membrane translocation of PKCepsilon in a portion of small DRG neurons. These results reveal a novel mechanism of NK-1 in primary sensory neurons via a possible autocrine and paracrine action of SP. Activation of NK-1 in these neurons induces heat hyperalgesia via PKCepsilon-mediated potentiation of TRPV1.
...
PMID:Neurokinin-1 receptor enhances TRPV1 activity in primary sensory neurons via PKCepsilon: a novel pathway for heat hyperalgesia. 1797 48

Desensitization is induced by the repeated administration of high doses of substance P (SP) or hemokinin-1 (HK-1). However, little information is available about the mechanisms involved in the induction of desensitization by these peptides. Thus, to characterize this desensitization, we examined the dose-dependent effect of these peptides, the effect of pretreatment with neurokinin 1(NK1) receptor antagonists, and the effect of pretreatment with inhibitors of protein kinases such as protein kinase A (PKA), protein kinase C (PKC), calcium/calmodulin kinase II (CaMKII) and mitogen-activated protein kinase kinase (MEK). The number of scratchings induced by 10(-3)M SP or HK-1 decreased following pretreatment with 10(-11)-10(-3)M SP or HK-1 with a marked reduction at 10(-3) and 10(-6)M SP or HK-1. The effect of NK1 receptor antagonists on desensitization induced by pretreatment with 10(-6)M SP was marked, whereas there was little effect of pretreatment with these antagonists on 10(-6)M HK-1-induced desensitization. Additionally, 10(-6)M SP- and HK-1-induced desensitization was attenuated by pretreatment with PKA, PKC and MEK inhibitors, except a CaMKII inhibitor that inhibited SP-induced desensitization. These results indicate that the receptor and kinases involved in HK-1-induced desensitization are partially different from those of SP.
...
PMID:Pharmacological characterization of desensitization in scratching behavior induced by intrathecal administration of hemokinin-1 in the rat. 1805 10

In animal models of Parkinson's disease, a supersensitive response to dopamine (DA) is associated with a switch in the coupling of striatal DA D1 receptors from a cyclic AMP/protein kinase A signaling pathway to one involving extracellular signal-regulated kinase/mitogen-associated protein kinase. In this study, we found that generation of organotypic striatal cultures, with concomitant loss of DA innervation, led to a downregulation in preprotachykinin-A gene expression, which was reinstated by D1 receptor activation in an extracellular signal-regulated kinase/mitogen-associated protein kinase-dependent manner. These data demonstrate that acute organotypic slice cultures recapitulate important changes in D1 receptor-mediated signal transduction seen in DA-denervated animals, providing a valuable model system to study denervation effects on DA signaling and striatal gene expression.
...
PMID:D1 receptor regulation of preprotachykinin-A gene by extracellular signal-regulated kinase pathway in striatal cultures. 1818 6

Substance P, acting via its neurokinin 1 receptor (NK1 R), plays an important role in mediating a variety of inflammatory processes. Its interaction with chemokines is known to play a crucial role in the pathogenesis of acute pancreatitis. In pancreatic acinar cells, substance P stimulates the release of NFkappaB-driven chemokines. However, the signal transduction pathways by which substance P-NK1 R interaction induces chemokine production are still unclear. To that end, we went on to examine the participation of mitogen-activated protein kinases (MAPKs) in substance P-induced synthesis of pro-inflammatory chemokines, monocyte chemoanractant protein-1 (MCP-I), macrophage inflammatory protein-lalpha (MIP-lalpha) and macrophage inflammatory protein-2 (MIP-2), in pancreatic acini. In this study, we observed a time-dependent activation of ERK1/2, c-Jun N-terminal kinase (JNK), NFkappaB and activator protein-1 (AP-1) when pancreatic acini were stimulated with substance P. Moreover, substance P-induced ERK 1/2, JNK, NFkappaB and AP-1 activation as well as chemokine synthesis were blocked by pre-treatment with either extracellular signal-regulated protein kinase kinase 1 (MEK1) inhibitor or JNK inhibitor. In addition, substance P-induced activation of ERK 112, JNK, NFkappaB and AP-1-driven chemokine production were attenuated by CP96345, a selective NK1 R antagonist, in pancreatic acinar cells. Taken together, these results suggest that substance P-NK1 R induced chemokine production depends on the activation of MAPKs-mediated NFkappaB and AP-1 signalling pathways in mouse pancreatic acini.
...
PMID:Effect of mitogen-activated protein kinases on chemokine synthesis induced by substance P in mouse pancreatic acinar cells. 1820 3

We examined proopiomelanocortin (POMC) mRNA and beta-endorphin expression in the hypothalamus of mice after various nociceptive stimuli. The time-course study (10 min, 30 min, 1 h, 2 h, and 10 h) showed that the POMC mRNA level significantly increases from 1 h after s.c. formalin injection and returns to the control level at 10 h. Intrathecal (i.t.) substance P (SP) injection also increases the hypothalamic POMC mRNA level from 1 h to 10 h. However, i.t. glutamate injection did not affect the hypothalamic POMC gene expression at all time points. We found that the POMC mRNA after s.c. formalin injection was located in the arcuate nucleus of the hypothalamus. In the same manner, beta-endorphin immunoreactivity was also increased in the hypothalamic arcuate nucleus. The expression of phosphorylated extracellular signal-regulated protein kinase 1/2 (pERK1/2), phosphorylated calcium/calmodulin-dependent protein kinase-IIalpha (pCaMK-IIalpha) protein and phosphorylated IkappaB (pIkappaB) protein was increased by s.c. formalin injection at various time points. We also found that increased pERK1/2, pCaMKIIalpha and pIkappaB protein after s.c. formalin injection was mainly located in the arcuate nucleus of hypothalamus in which cells containing beta-endorphin after s.c. formalin injection also express pERK1/2, pCaMK-IIalpha and pIkappaB immunoreactivity. In addition, formalin-induced POMC mRNA expression was significantly reduced by 10 min, pretreatment with i.c.v. PD98059 (mitogen-activated protein kinase (MAPK) pathways inhibitor; 6.6 mug) and KN93 (pCaMK-II inhibitor; 20 mug). In conclusion, POMC mRNA expression in the arcuate nucleus of the hypothalamus was increased by inflammatory pain stimuli, in which pERK1/2, pCaMK-IIalpha and NFkappaB may play an important role in the expression of the hypothalamic POMC gene and beta-endorphin expression.
...
PMID:Characterization of the hypothalamic proopiomelanocortin gene and beta-endorphin expression in the hypothalamic arcuate nucleus of mice elicited by inflammatory pain. 1832 77

The present study was designed to characterize the urinary bladder-derived relaxant factor that was demonstrated by acetylcholine-induced relaxation response in a coaxial bioassay system consisting of rat bladder as the donor organ and rat anococcygeus muscle as the assay tissue. The concentration-dependent relaxation to acetylcholine (10 nM-1 mM) was inhibited by atropine but was not altered by the antagonists of calcitonin gene-related peptide (CGRP 8-37), vasoactive intestinal peptide (VIP 6-28), tachykinin NK1 (L-732138), tachykinin NK2 (MEN-10376), tachykinin NK3 (SB-218795), purinergic P2 (PPADS) and adenosine (CGS 15943) receptors as well as alpha-chymotrypsin. Adenylate cyclase inhibitor SQ-22536 and protein kinase A inhibitor KT-5720 significantly inhibited the acetylcholine response while guanylate cyclase inhibitor ODQ, and protein kinase C inhibitor H-7 did not have any effect. The P2X agonist alpha,beta-methylene ATP (10 nM-0.1 mM) also produced concentration-dependent relaxation response that was inhibited by PPADS, SQ-22536 and KT-5720 in the coaxial bioassay system. In bladder strips, acetylcholine and alpha,beta-methylene ATP elicited concentration-dependent contractions that were not altered in the presence of SQ-22536 and KT-5720. In conclusion, the urinary bladder-derived relaxant factor that was recognized by the coaxial bioassay system is neither a peptide of the bladder neurons nor a purinergic mediator but adenylate cyclase and protein kinase A are involved in its release and/or relaxant effect. Furthermore, activation of purinergic P2X receptors besides the muscarinic receptors leads to the release of this factor.
...
PMID:Rat urinary bladder-derived relaxant factor: studies on its nature and release by coaxial bioassay system. 1862 Oct 43


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>