31 entries found for : it-40
Kunimura K, Fukui Y (2021) The molecular basis for IL-31 production and IL-31-mediated itch transmission: from biology to drug development. Int Immunol 33(12):731-736. doi: 10.1093/intimm/dxab065Objective: To investigate the molecular mechanisms of how IL-31 is produced in helper T cells upon stimulation and transmits the itch sensation to the brain.
Summary: This review highlights recent findings that show the functional significance of endothelial PAS domain 1 (EPAS1) and neurokinin B (NKB) in the IL-31-induced itch sensation.
Usage: Neurons expressing the Nppb receptor were specifically ablated by intrathecal injection of Nppb-SAP. Treatment with Bombesin-SAP reduced IL-31-induced scratching.
Related Products: Bombesin-SAP (Cat. #IT-40), Nppb-SAP (Cat. #IT-69)
Chen ZF (2021) A neuropeptide code for itch. Nat Rev Neurosci 22(12):758-776. doi: 10.1038/s41583-021-00526-9 Related Products: Bombesin-SAP (Cat. #IT-40)
Liu X, Wang Y, Tao T, Zeng L, Wang D, Wen Y, Li Y, Zhao Z, Tao A (2021) GRPR/extracellular signal-regulated kinase and NPRA/extracellular signal-regulated kinase signaling pathways play a critical role in spinal transmission of chronic itch. J Invest Dermatol 141(4):863-873. doi: 10.1016/j.jid.2020.09.008Summary: This study investigates whether there are certain key signaling molecules downstream of the recently identified peptides mediating itch in the spinal cord. Bombesin-SAP completely abolished extracellular signal-regulated kinase (ERK) activation. ERK was the most highly activated by their agonists BNP (Nppb, brain-derived natriuretic peptide) and octreotide. Nppb-SAP only partially reduced pERK in cervical spinal cord.
Related Products: Bombesin-SAP (Cat. #IT-40), Nppb-SAP (Cat. #IT-69)
Central opioid receptors mediate morphine-induced itch and chronic itch via disinhibition
Wang Z, Jiang C, Yao H, Chen O, Rahman S, Gu Y, Zhao J, Huh Y, Ji RR (2021) Central opioid receptors mediate morphine-induced itch and chronic itch via disinhibition. Brain 144(2):665-681. doi: 10.1093/brain/awaa430Summary: Itch is a common side effect of opioids, particularly as a result of epidural or intrathecal administration. Notably, morphine-elicited itch was suppressed by intrathecal administration of NPY and abolished by spinal ablation of GRPR+ neurons with intrathecal injection of Bombesin-SAP.
Usage: For ablation of GRPR+ neurons, mice were given an intrathecal injection of 400 ng Bombesin-SAP or Blank-SAP (control) 10 days before behavioral testing.
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Spinal GRPR and NPRA contribute to chronic itch in a murine model of allergic contact dermatitis.
Liu X, Wang D, Wen Y, Zeng L, Li Y, Tao T, Zhao Z, Tao A (2020) Spinal GRPR and NPRA contribute to chronic itch in a murine model of allergic contact dermatitis. J Invest Dermatol 140(9):1856-1866.e7. doi: 10.1016/j.jid.2020.01.016Objective: The authors investigated the peripheral and spinal mechanisms responsible for prolonged itch in a mouse model of allergic contact dermatitis (ACD) induced by squaric acid dibutylester (SADBE).
Summary: Targeting gastrin-releasing peptide receptor (GRPR) and natriuretic peptide receptor A (NPRA) may provide effective treatments for ACD associated chronic pruritus.
Usage: A single dose of Bombesin-SAP (400 ng) and Blank-SAP (400 ng) or two doses of Nppb-SAP (BNP-SAP; 650 ng) and Blank-SAP (650 ng) were administered via intrathecal injection.
Related Products: Bombesin-SAP (Cat. #IT-40), Nppb-SAP (Cat. #IT-69), Blank-SAP (Cat. #IT-21)
Kiguchi N, Uta D, Ding H, Uchida H, Saika F, Matsuzaki S, Fukazawa Y, Abe M, Sakimura K, Ko MC, Kishioka S (2020) GRP receptor and AMPA receptor cooperatively regulate itch-responsive neurons in the spinal dorsal horn. Neuropharmacology 170:108025. doi: 10.1016/j.neuropharm.2020.108025Objective: To investigate the mechanisms for the activation of itch-responsive GRPR+ neurons in the spinal dorsal horn (SDH).
Summary: These findings demonstrate that GRP and glutamate cooperatively regulate GRPR+ AMPAR+ neurons in SDH, mediating itch sensation. GRP–GRPR and the glutamate–AMPAR system may play pivotal roles in the spinal transmission of itch in rodents and nonhuman primates.
Usage: Bombesin-SAP and Blank-SAP were administered i.t. (5 μg/5 μl).
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Barry DM, Liu XT, Liu B, Liu XY, Gao F, Zeng X, Liu J, Yang Q, Wilhelm S, Yin J, Tao A, Chen ZF (2020) Exploration of sensory and spinal neurons expressing gastrin-releasing peptide in itch and pain related behaviors. Nat Commun 11(1):1397. doi: 10.1038/s41467-020-15230-yObjective: To determine the role of GRP in sensory neurons.
Summary: GRP is a neuropeptide in sensory neurons for nonhistaminergic itch, and GRP sensory neurons are dedicated to itch transmission.
Usage: Bombesin-SAP (200 ng/5 μL, i.t.) was injected 2 weeks prior to optical stimulation.
Related Products: Bombesin-SAP (Cat. #IT-40)
More than scratching the surface: recent progress in brain mechanisms underlying itch and scratch.
Liu X, Miao XH, Liu T (2020) More than scratching the surface: recent progress in brain mechanisms underlying itch and scratch. Neurosci Bull 36(1):85-88. doi: 10.1007/s12264-019-00352-1Summary: The discovery of descending neural circuitry to drive the itch-scratching cycle may provide potential therapeutic targets in the central nervous system for the management of chronic itch.
Usage: To ablate the spinal GRPR+ neurons, mice were intrathecally injected with Bombesin-SAP or Blank-SAP (400 ng/5 mL).
Related Products: Bombesin-SAP (Cat. #IT-40)
Identification of a spinal circuit for mechanical and persistent spontaneous itch.
Pan H, Fatima M, Li A, Lee H, Cai W, Horwitz L, Hor CC, Zaher N, Cin M, Slade H, Huang T, Xu XZS, Duan B (2019) Identification of a spinal circuit for mechanical and persistent spontaneous itch. Neuron 103(6):1135-1149.e6. doi: 10.1016/j.neuron.2019.06.016
Objective: To identify a spinal circuit for mechanical and persistent spontaneous itch.
Summary: Findings indicate excitatory interneurons expressing Urocortin 3::Cre (Ucn3+) in the dorsal spinal cord as a valid cellular target for future therapeutic interventions against chronic itch, without affecting normal touch.
Usage: To ablate spinal GRPR+ neurons, mice were given a single intrathecal injection of either Bombesin-SAP or Blank-SAP (400 ng in 10 mL sterile saline). To ablate spinal Npra+ neurons, mice were given a single intrathecal injection of either Nppb-SAP or Blank-SAP (5 mg in 10 mL sterile saline).
Related Products: Bombesin-SAP (Cat. #IT-40), Nppb-SAP (Cat. #IT-69), Blank-SAP (Cat. #IT-21)
Selective role of neurokinin B in IL-31–induced itch response in mice.
Sakata D, Uruno T, Matsubara K, Andoh T, Yamamura K, Magoshi Y, Kunimura K, Kamikaseda Y, Furue M, Fukui Y (2019) Selective role of neurokinin B in IL-31–induced itch response in mice. J Allergy Clin Immunol 144(4):1130-1133. doi: 10.1016/j.jaci.2019.06.031
Objective: To examine the physiological significance of neurokinin B in IL-31–induced itch sensation.
Summary: IL-31–induced scratching was unaffected by intrathecal injection of Nppb-SAP. In contrast,treatment with Bombesin-SAP reduced IL-31–induced scratching. Neurokinin B acts upstream of GRP to transmit IL-31–induced itch sensation.
Usage: Intrathecal injection
Related Products: Bombesin-SAP (Cat. #IT-40), Nppb-SAP (Cat. #IT-69), Blank-SAP (Cat. #IT-21), NKB-SAP (Cat. #IT-63)
Acton D, Ren X, DiCostanzo S, Dalet A, Bourane S, Bertocchi I, Eva C, Goulding M (2019) Spinal neuropeptide Y1 receptor-expressing neurons form an essential excitatory pathway for mechanical itch. Cell Reports 28(3):625-639.e6 . doi: 10.1016/j.celrep.2019.06.033Objective: To determine the central pathway for mechanical itch.
Summary: NPY-Y1 signaling regulates the transmission of innocuous tactile information by establishing biologically relevant thresholds for touch discrimination and mechanical itch reflexes. Neither the evoked nor spontaneous scratching seen following activation of Y1Cre neurons was affected by ablation of the GRPR+ neurons. NK1R+ neuron ablation failed to modulate mechanically evoked itch.
Usage: P28 mice were given a single intrathecal (i.t.) injection of either Bombesin-SAP (400 ng in 5 mL 0.9% sterile saline) to ablate GRPR+ cells or SSP-SAP to ablate NK1r+ neurons (100 ng in 5 mL 0.9% sterile saline). Littermate controls received Blank-SAP (equal mass in 5 mL 0.9% sterile saline).
Related Products: Bombesin-SAP (Cat. #IT-40), SSP-SAP (Cat. #IT-11), Blank-SAP (Cat. #IT-21)
Gao ZR, Chen WZ, Liu MZ, Chen XJ, Wan L, Zhang XY, Yuan L, Lin JK, Wang M, Zhou L, Xu XH, Sun YG (2019) Tac1-expressing neurons in the periaqueductal gray facilitate the itch-scratching cycle via descending regulation. Neuron 101(1):45-59.e9. doi: 10.1016/j.neuron.2018.11.010Objective: To determine the neural mechanism promoting the itch-scratching cycle.
Summary: Ablation of Tac1+ but not SST+ neurons decreases itch-induced scratching behavior. l/vlPAG Tac1+ neurons Induce Scratching Behavior via a Descending Pathway.
Usage: To ablate the spinal GRPR+ neurons, mice were intrathecally injected with Bombesin-SAP or Control Blank-SAP (400 ng/5 mL).
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Circuit dissection of the role of somatostatin in itch and pain
Huang J, Polgár E, Solinski HJ, Mishra SK, Tseng PY, Iwagaki N, Boyle KA, Dickie AC, Kriegbaum MC, Wildner H, Zeilhofer HU, Watanabe M, Riddell JS, Todd AJ, Hoon MA (2018) Circuit dissection of the role of somatostatin in itch and pain. Nat Neurosci 21(5):707-716. doi: 10.1038/s41593-018-0119-zObjective: To determine the role of somatostatin in itch and pain.
Summary: Results define the neural circuit underlying somatostatin-induced itch and characterize a contrasting antinociceptive role for the peptide.
Usage: Ablation of Npr1- and GRPR-expressing spinal cord interneurons was accomplished by intrathecal (segment L3/4) injection of Nppb-SAP (4 μg/10 μL) and Bombesin-SAP (2.5 μg) respectively.
Related Products: Bombesin-SAP (Cat. #IT-40), Nppb-SAP (Cat. #IT-69)
Itch induces conditioned place aversion in mice
Mu D, Sun Y-G (2017) Itch induces conditioned place aversion in mice. Neuroscience Letters 658:91-96.. doi: 10.1016/j.neulet.2017.08.046
Summary: Consistently, ablation of itch‐specific neurons that express gastrin‐releasing peptide receptor in the spinal cord also abolished itch‐induced Conditioned Place Aversion (CPA), confirming that itch‐induced CPA is dependent on the spinal itch circuit.
Usage: Mice were given a single intrathecal injection (400 ng/5 μl each) of Bombesin-SAP (Cat. #IT-40) or Control Blank-SAP (Cat. #IT-21).
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Spinal mechanisms of itch transmission
Barry DM, Munanairi A, Chen Z-F (2018) Spinal mechanisms of itch transmission. Neurosci Bull 34:156-164. doi: 10.1007/s12264-017-0125-2 Related Products: Bombesin-SAP (Cat. #IT-40)
Molecular and neural basis of contagious itch behavior in mice
Yu Y-Q, Barry DM, Hao Y, Liu X-T, Chen Z-F (2017) Molecular and neural basis of contagious itch behavior in mice. Science 355:1072. doi: 10.1126/science.aak9748
Summary: The authors selectively ablated the SCN gastrin-releasing peptide receptor (GRPR) neurons using Bombesin-SAP (Cat. #IT-40), a peptide-conjugated toxin that kills GRPR neurons in the spinal cord. After bilateral injection of Bombesin-SAP into the SCN, immunohistochemistry showed that Bombesin-SAP injection resulted in ablation of SCN GRPR+ neurons.
Related Products: Bombesin-SAP (Cat. #IT-40)
The peptidergic control circuit for sighing.
Li P, Janczewski W, Yackle K, Kam K, Pagliardini S, Krasnow M, Feldman J (2016) The peptidergic control circuit for sighing. Nature 530:293-297. doi: 10.1038/nature16964
Summary: Sighs are often associated with relief or sadness, but rodents sigh spontaneously dozens of times per hour. There are physiological benefits to sighing, including enhancement of gas exchange and preservation of lung integrity. The authors identify a peptidergic sigh control circuit in the retrotrapezoid nucleus/parafacial respiratory group of the mouse brain that projects to the pre-Bötzinger complex. Mice received bilateral 6.2-ng injections of Bombesin-SAP (Cat. #IT-40) into the pre-Bötzinger complex. Blank-SAP (Cat. #IT-21) was used as control. Elimination of the bombesin receptor-expressing neurons or inhibition of neuromedin B receptor-expressing neurons suppressed sighing. Interfering with the activity of both receptors abolished sigh activity while leaving normal breathing intact. The data suggest that overlapping peptidergic pathways are the core of a sigh control circuit.
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Gate control of mechanical itch by a subpopulation of spinal cord interneurons.
Bourane S, Duan B, Koch S, Dalet A, Britz O, Garcia-Campmany L, Kim E, Cheng L, Ghosh A, Ma Q, Goulding M (2015) Gate control of mechanical itch by a subpopulation of spinal cord interneurons. Science 350:550-554. doi: 10.1126/science.aac8653
Summary: Light mechanical stimulation of the hairy skin can induce a form of itch known as mechanical itch. This itch sensation is normally suppressed by inputs from mechanoreceptors, however, in many forms of chronic itch, including alloknesis, this gating mechanism is lost. Scientists demonstrated that a population of spinal inhibitory interneurons (INs), that are defined by the expression of neuropeptide Y::Cre (NPY::Cre), act to gate mechanical itch. Mice in which dorsal NPY::Cre-derived neurons are selectively ablated or silenced develop mechanical itch without an increase in sensitivity to chemical itch or pain. This chronic itch state is histamine-independent and is transmitted independently of the GRP-GRPR signaling pathway. The scientists thereby revealed a dedicated spinal cord inhibitory pathway that gates the transmission of mechanical itch. Mice were given an intrathecal injection of 400 ng of Bombesin-SAP (Cat. #IT-40) in 10 ml of sterile saline to ablate GRPR-expressing neurons.
Related Products: Bombesin-SAP (Cat. #IT-40)
A central role for spinal dorsal horn neurons that express neurokinin-1 receptors in chronic itch.
Akiyama T, Nguyen T, Curtis E, Nishida K, Devireddy J, Delahanty J, Carstens M, Carstens E (2015) A central role for spinal dorsal horn neurons that express neurokinin-1 receptors in chronic itch. Pain 156:1240-1246. doi: 10.1097/j.pain.0000000000000172
Summary: Chronic itch is caused by increased sensitivity of itch-signaling pathways. It can be generated by normally itchy stimuli (hyperknesis) and by normally non-itchy light touch (alloknesis). The authors used an ovalbumin-induced atopic dermatitis model to study chronic itch in mice. The mice received 400-ng intrathecal injections of Bombesin-SAP (Cat. #IT-40), SSP-SAP (Cat. #IT-11), or the control Blank-SAP (Cat. #IT-21). While Bombesin-SAP significantly attenuated hyperknesis, it had no effect on spontaneous scratching or alloknesis. SSP-SAP reduced all behavioral signs of chronic itch.
Related Products: Bombesin-SAP (Cat. #IT-40), SSP-SAP (Cat. #IT-11), Blank-SAP (Cat. #IT-21)
Akiyama T, Tominaga M, Davoodi A, Nagamine M, Takamori K, Carstens MI, Carstens E (2014) Spinal antinociceptive effect of gastrin releasing peptide (GRP) via GABAergic inhibitory interneurons expressing the GRP receptor (GRPR). Neuroscience 2014 Abstracts 158.02. Society for Neuroscience, Washington, DC.
Summary: GRPR-expressing dorsal horn neurons signal itch. We investigated a role for such neurons in modulating the spinal neurotransmission of mechanical and heat pain in mice. In behavioral studies, we measured heat and mechanical paw withdrawal thresholds using Hargreaves and von Frey assays, respectively. Mice received intrathecal (it) administration of one of following (5 µL volume); bombesin (6.2 pmol), GRP (0.1 nmol), and GRPR antagonists RC-3095 (0.03 nmol) and BW2258U89 (1.5 nmol). It administration of bombesin or GRP significantly reduced both heat and mechanical withdrawal thresholds with a maximal effect 10 min post-administration. In contrast, it administration of RC-3095 and BW2258U89 significantly increased both heat and mechanical withdrawal thresholds with a maximal effect 10 min post-administration. Mice treated with it bombesin-saporin to ablate GRPR-expressing spinal neurons exhibited reduced heat and mechanical withdrawal thresholds. It GRP failed to elicit heat and mechanical hyperalgesia in these mice. In electrophysiological recordings from superficial lumbar dorsal horn neurons, either bombesin or RC-3095 was spinally applied during responses elicited by noxious mechanical or heat stimulation of the cutaneous receptive field on the hindpaw. Bombesin increased both noxious mechanical- and heat-evoked activity in bombesin-sensitive neurons, while RC-3095 decreased noxious heat-evoked activity. In bombesin-insensitive neurons, bombesin decreased both noxious mechanical- and heat-evoked activity, while RC-3095 increased both. We additionally employed a double-label strategy to investigate if GRPR-expressing dorsal horn neurons coexpressed GABA, a molecular marker of inhibitory interneurons. Approximately 10% of GRPR-positive neurons were immunopositive for GABA. These results indicate that a subset of GRPR-expressing neurons function as interneurons in a circuit that suppresses nociceptive transmission in the dorsal horn. Noxious mechanical and heat stimuli activate GRPR-expressing dorsal horn neurons. A GABAergic subset of these may serve as inhibitory interneurons that contribute to inhibition of spinal neurons signaling heat and mechanical pain. Alternatively, GRPR-expressing neurons may drive other subsets of inhibitory interneurons. The antinociceptive circuit described here can be activated by pruritogens. We propose that the relative activity in antinociceptive and antipruritic circuits within the dorsal horn modulates itch- and pain-signaling ascending neurons to result in the perception of itch or pain.
Related Products: Bombesin-SAP (Cat. #IT-40)
Role of spinal bombesin-responsive neurons in nonhistaminergic itch.
Akiyama T, Tominaga M, Takamori K, Carstens M, Carstens E (2014) Role of spinal bombesin-responsive neurons in nonhistaminergic itch. J Neurophysiol 112:2283-2289. doi: 10.1152/jn.00409.2014
Summary: Recent papers have demonstrated that pruritogen-evoked scratching behavior is reduced or eliminated by intrathecal injection of Bombesin-SAP (Cat. #IT-40). In this work the authors build on those data by investigating if spinal neurons that are responsive to pruritogens administered intradermally are also responsive to a spinal infusion of bombesin. Through the use of intradermal chloroquine injections, spinal superfusion of bombesin, and noxious pinch, the overlap of neurons processing itch and nociception was examined. The results demonstrate that chloroquine- and bombesin-sensitive neurons are involved in the transmission of itch, and that these are a separate neuronal population from those involved in nociception.
Related Products: Bombesin-SAP (Cat. #IT-40)
Cross-inhibition of NMBR and GRPR signaling maintains normal histaminergic itch transmission.
Zhao Z, Wan L, Liu X, Huo F, Li H, Barry D, Krieger S, Kim S, Liu Z, Xu J, Rogers B, Li Y, Chen Z (2014) Cross-inhibition of NMBR and GRPR signaling maintains normal histaminergic itch transmission. J Neurosci 34:12402-12414. doi: 10.1523/JNEUROSCI.1709-14.2014
Summary: After itch detection, the itch pathway moves through an array of G-protein coupled receptors and transient receptor potential channels in dorsal root ganglion neurons into dorsal horn neurons which integrate and transduce these signals, sending them to the somatosensory cortex. The purpose of this work is to clarify whether gastrin-releasing peptide (GRP) or B-type natriuretic peptide regulates histaminergic itch. Several strains of knockout mice received 200, 300, or 400 ng intrathecal injections of bombesin-SAP (Cat. #IT-40). Blank-SAP (Cat. #IT-21) was used as a control. The data further define the respective functions of the neuromedin B receptor and GRP receptor in itch, and reveals a working relationship between the different interneuron populations.
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Sasaki A, Adhikari S, Andoh T, Kuraishi Y (2013) BB2 bombesin receptor-expressing spinal neurons transmit herpes-associated itch by BB2 receptor-independent signaling. Neuroreport 24(12):652-656. doi: 10.1097/WNR.0b013e32836352d8
Summary: Using a skin rash model created by inoculating mice with human herpes virus, bombesin receptor-expressing spinal neurons were lesioned intrathecally with 400 ng of Bombesin-SAP (Cat. #IT-40). Lesioned animals displayed reduced scratching, but licking (due to pain) was not reduced.
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
The GRP peptide and the GRPR-positive interneurons control fear acquisition and extinction.
Zushida K, Light K, Uchida S, Hevi C, Shumyatsky GP (2012) The GRP peptide and the GRPR-positive interneurons control fear acquisition and extinction. Neuroscience 2012 Abstracts 496.03. Society for Neuroscience, New Orleans, LA.
Summary: The gastrin releasing peptide (GRP) is the marker of the neural circuits relaying fear-related conditioned stimulus (CS) information to the amygdala. The GRP is expressed by principal cells and the GRP-receptor (GRPR) is expressed by interneurons. The GRPR is expressed in the amygdala and hippocampus. To examine the role of the GRPR-positive interneurons in these two brain areas, we performed local injections of the bombesin-saporin (SAP)-toxin, which selectively eliminates the GRPR-expressing cells. The intra-BLA [lateral (LA) and basal nuclei (BA) of amygdala] injection of bombesin-SAP before fear conditioning significantly enhanced cued, but not contextual fear memory. We did not observe any significant effect of post-training intra-BLA injections of bombesin-SAP on fear memory recall. Also, there were no significant effects of bombesin-SAP on acquisition of contextual and cued fear memory in mice injected bombesin-SAP into LA, BA and central amygdala (CeA), respectively. Also, we examined cued fear memory in the GRP knockout mice and found significant enhancement in their cued fear memory. These results support the idea that GRPR-expressing interneurons play an inhibitory role in acquisition of fear memory and suggested inhibitory effect by the GRPR-expressing GABA interneurons on fear memory requires both LA and BA but not CeA.
Related Products: Bombesin-SAP (Cat. #IT-40)
A nociceptive signaling role for neuromedin B.
Mishra SK, Holzman S, Hoon MA (2012) A nociceptive signaling role for neuromedin B. J Neurosci 32(25):8686-8695. doi: 10.1523/JNEUROSCI.1533-12.2012
Summary: Previous work suggests that neuromedin B (NMB) is involved in nociception. Direct injection of the peptide causes nociceptive sensitization, while NMB antagonists attenuate sensitization in reponse to nerve stimulation with mustard oil. Specific subsets of dorsal horn interneurons were eliminated by administering either 10 μg of the custom conjugate neuromedin B-SAP, 0.13 μg of SSP-SAP (Cat. #IT-11), or 1.3 μg of bombesin-SAP (Cat. #IT-40). Blank-SAP (Cat. #IT-21) was used as a control. The data indicate that NMB may be involved in the perception of thermal sensation, but not mechanical or pruritic sensation.
Related Products: NMB-SAP (Cat. #IT-70), SSP-SAP (Cat. #IT-11), Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Han N, Zu JY, Chai J (2012) Spinal bombesin-recognized neurones mediate more nonhistaminergic than histaminergic sensation of itch in mice. Clin Exp Dermatol 37(3):290-295. doi: 10.1111/j.1365-2230.2011.04314.x
Summary: The authors administered 400 ng of Bombesin-SAP (Cat. #IT-40) to the lumbar spinal subarachnoid space of rats and evaluated the distribution of Fos-positive cells in the dorsal horn after stimulation. Saporin (Cat. #PR-01) was used as a control. The results demonstrate that the neurons eliminated by Bombesin-SAP are critical to both acute and chronic itch pathways, although they have more effect on nonhistaminergic sensation.
Related Products: Bombesin-SAP (Cat. #IT-40), Saporin (Cat. #PR-01)
Unidirectional cross-activation of GRPR by MOR1D uncouples itch and analgesia induced by opioids.
Liu XY, Liu ZC, Sun YG, Ross M, Kim S, Tsai FF, Li QF, Jeffry J, Kim JY, Loh HH, Chen ZF (2011) Unidirectional cross-activation of GRPR by MOR1D uncouples itch and analgesia induced by opioids. Cell 147(2):447-458. doi: 10.1016/j.cell.2011.08.043
Summary: Recent work has begun to define the different pathways used by itch and pain. This study was designed to investigate whether opioids cause the itch sensation by gastrin releasing peptide receptor activation. Mice received intrathecal injections of bombesin-SAP (Cat. #IT-40) in order to investigate the coexpression of various signaling molecules in the spinal cord. Blank-SAP (Cat. #IT-21) was used as a control. The data suggest that opioid-induced itch is independent of opioid analgesia, and is controlled through a mu-opioid receptor isoform.
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Itch signaling in the nervous system.
Jeffry J, Kim S, Chen ZF (2011) Itch signaling in the nervous system. Physiology (Bethesda) 26(4):286-92. doi: 10.1152/physiol.00007.2011
Summary: This review examines recent work done to elucidate the molecular mechanisms behind the sensation of itch. The progress of mouse genetics has allowed the field to move beyond clinical and physiological studies, toward a better understanding of the signaling involved in nonhistaminergic itch. One study discussed used bombesin-SAP (Cat. #IT-40) in mice to ablate GRPR-positive neurons in the dorsal horn. This lesion reduced scratching in response to pruritogens, but did not affect pain behavior‚ indicating that pain and itch use entirely different pathways.
Related Products: Bombesin-SAP (Cat. #IT-40)
Li C, Back S, Lee J, Baek SK, Na H (2010) Gastrin-releasing peptide receptor in the spinal cord mediates mechanical allodynia following nerve injury. Neuroscience 2010 Abstracts 176.2/OO4. Society for Neuroscience, San Diego, CA.
Summary: Gastrin-releasing peptide receptor (GRPR) has been suggested as an itch-specific gene in the spinal cord (Sun et al., Nature, 2009). They described that selective ablation of GRPR-expressing lamina I neurons led to deficits in itch-related scratching behaviors without any effects on pain behaviors including nerve injury-induced mechanical allodynia. It has been known that two types of mechanical allodynia, such as static and dynamic allodynia, can be detectable in neuropathic patients, and may be mediated by distinct mechanisms. In the present study, we investigated the role of spinal GRPR in each of static and dynamic allodynia using both rat- and mouse-tail models of neuropathic pain. Bombesin-saporin (bombesin-sap) was administered intrathecally to ablate spinal GRPR-expressing neurons. Scratching behaviors evoked by pruritogenic agents, such as serotonin and chloroquine, and physiological pain behaviors were analyzed before nerve injury. Static or dynamic allodynia was assessed by the application of von Frey filaments to the tail or brushing the tail with a filament, respectively. RC3095, a GRPR antagonist, was given intrathecally to see its effects on static and dynamic allodynia in neuropathic rats. Bombesin-sap treatment resulted in reduction of GRPR-immunoreactive cells in lamina I of spinal dorsal horn and scratching deficits. Physiological pain behaviors of these animals were not different from those of control animals. Following the partial injury of tail-innervating nerves, animals treated with bombesin-sap exhibited comparable dynamic allodynia to control one. However, they failed to manifest static allodynia during the entire experimental period. In addition, RC3095 relieved static, but not dynamic, allodynia. These findings suggest that spinal GRPR mediates nerve injury-induced static mechanical allodynia as well as itching sensation in normal state.
Related Products: Bombesin-SAP (Cat. #IT-40)
Chen ZF, Sun YG, Zhao ZQ, Meng XL, Yin J, Liu XY (2009) Featured Article: Ablation of GRPR+ neurons in the spinal cord by bombesin-saporin knocks out itch sensation in mice without affecting pain circuit. Targeting Trends 10(4)
Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)
Read the featured article in Targeting Trends.
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Cellular basis of itch sensation.
Sun YG, Zhao ZQ, Meng XL, Yin J, Liu XY, Chen ZF (2009) Cellular basis of itch sensation. Science 325:1531-1534. doi: 10.1126/science.1174868
Summary: Whether itch and pain use separate neuronal pathways has long been a subject of debate. The authors injected 400 ng of bombesin-SAP (Cat. #IT-40) into the intrathecal space of mice and examined itch and pain behavior. Lesioned mice had dramatic deficits in all itch behavior tested regardless of the histamine dependence of the itch. All pain behaviors, however, were left intact. These data indicate that the gastrin-releasing peptide receptor-expressing neurons are essential for itch transmission.
Related Products: Bombesin-SAP (Cat. #IT-40)