The pre-Bötzinger complex (pre-BötC) residing in the ventrolateral medulla oblongata, is thought to be the kernel of respiratory rhythmogenesis. Episodic hypoxia exerts respiratory long-term facilitation, being recognized as electrophysiological characteristic of respiratory motor neuroplasticity. Our previous study demonstrated up-regulated expression of phospho-protein kinase C θ (P-PKCθ) in the pre-BötC of rats receiving chronic intermittent hypoxic (CIH) challenge. The present study was aimed to examine subcellular distribution of P-PKC substrates (P-PKCsub) and explore PKC down-stream targeting proteins in the pre-BötC in normoxic and CIH rats. Using neurokinin-1 receptor (NK1R) as a marker of the pre-BötC, P-PKCsub immunoreactivity was revealed by immunofluorescence and immuno-electron microscopic double-labeling in the pre-BötC. Western blot was applied to analyze P-PKCsub proteins in ventrolateral medulla, containing the pre-BötC. The results showed that NK1R immunoreactivity (NK1R-ir) was expressed mainly along plasma membranes of somata and processes, outlining pre-BötC neurons under the light microscope. P-PKCsub immunoreactive (P-PKCsub-ir) fluorophores in dot-like appearance appeared in somata and processes. Some were in close apposition to plasma membranes. A majority of P-PKCsub-ir neurons was found with NK1R-ir. CIH challenge up-regulated the expression of P-PKCsub proteins in the ventrolateral medulla. Under the electron microscope, NK1R-ir product was found to distribute along the inner membrane surfaces of somata and dendrites. P-PKCsub-ir gold particles were located in somata and dendrites, and some were distributed along the inner membrane surfaces, as well as in the endoplasmic reticulum and postsynaptic dense body. These results suggest that CIH challenge up-regulates the expression of P-PKCsub proteins, probably including some receptor proteins in the postsynaptic membrane, which may contribute to respiratory neuroplasticity via activation of PKCθ in the pre-BötC.
Animals ; Hypoxia ; Medulla Oblongata/metabolism* ; Neurons/metabolism* ; Rats ; Rats, Sprague-Dawley ; Receptors, Neurokinin-1/metabolism*

OBJECTIVETo explore the relationship between neuropeptide substance P (SP) and wound healing in scalded rats.

METHODS(1) Scalded rats with different degrees of scald injury were employed as the experimental model and were sacrificed at 24 post scald hour (PSH), and on 3, 7 and 14 post scald days (PSD). The SP content in the wound was detected with radioimmunoassay method. (2) The murine granulation tissue fibroblasts (GTF) were cultured with different culture media, and divided into control, SP and Spantide (SP receptor antagonism) groups. The effects of SP and Spantide on the cellular activity and apoptotic rate of murine GTF were assessed in vitro.

RESULTSThere was significant difference of the SP content among the superficial (145 +/- 78) ng/g, partial (94 +/- 48 ng/g) and full thickness (53 +/- 27 ng/g) scald wounds at 24 PSH (P < 0.01), while the SP content in partial thickness burn wound on 3 and 7 PSD obviously increased; and that in deep partial thickness burn wound obviously increased on 7 and 14 PSD. But the SP content remained unchanged in full thickness scald wound. (2) SP could promote the activity of GTF and inhibit its apoptosis (The GTF activity in control, SP groups were 0.21 +/- 0.05, 0.36 +/- 0.07, respectively, P < 0.01). Spantide could inhibit the interaction between SP and GTF.

CONCLUSIONSP can promote GTF proliferation, and the SP content in wound is closely associated with the depth of the injury and wound healing capacity.

Animals ; Burns ; metabolism ; pathology ; Cell Proliferation ; Disease Models, Animal ; Female ; Fibroblasts ; cytology ; Male ; Rats ; Rats, Wistar ; Receptors, Neurokinin-1 ; metabolism ; Substance P ; analogs & derivatives ; pharmacology ; Wound Healing

OBJECTIVETo investigate the preventive and therapeutic effects of Xiaobanxia Fuling Decoction (XBFD) on cisplatin-induced pica rats and to study its mechanism.

METHODSForty-two male Sprague-Dawley rats were randomly divided into the following 7 groups, i.e., the blank control group, the model group, the high-, middle-, and low-dose XBFD groups (at the daily dose of 30, 15, and 7. 5 g/kg, respectively), the aprepitant (at the daily dose of 13 mg/kg), and pure Chinese medicine group (at the daily dose of XBFD 15 g/kg), 6 in each group. On the 3rd day of this study, 3 mg/kg cisplatin was intraperitoneally injected to rats except the blank control group and the model group to establish the pica rat model. The consumptions of kaolin, food, and the general situation of rats were observed. The protein and mRNA expressions of neurokinin 1 receptor (NK1R) in both the medulla oblongata and the gastric antrum were measured by immunohistochemical assay and Real-time fluorescent quantitative PCR respectively on the sixth day of this study.

RESULTSOn the third, fourth, and fifth day of this study, the consumption of kaolin of rats significantly increased when compared with the blank control group (P<0.01). Compared with the model group, the consumption of kaolin significantly decreased in the high-, middle-, and low-dose XBFD groups on the third, fourth, and fifth day of this study (P<0.05). The food intake of rats in the high-dose XBFD groups significantly increased when compared with the model group on the third day of this study (P<0.05). The protein and mRNA expressions of NK, R in the medulla oblongata and the gastric antrum significantly decreased in the high- and middle-dose XBFD groups when compared with the model group (P<0.05).

CONCLUSIONSXBFD could prevent and treat cisplatin-induced pica in rats. Its effect might be correlated with decreasing expressions of NK, R in the medulla oblongata and the gastric antrum.

Animals ; Cisplatin ; adverse effects ; Drugs, Chinese Herbal ; therapeutic use ; Male ; Pica ; chemically induced ; drug therapy ; prevention & control ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Receptors, Neurokinin-1 ; metabolism

ObjectiveTo investigate the expressions of substance P (SP) and neurokinin-1 receptor (NK-1R) in the posterior horn of the L5－S2 spinal cord in the rat model of chronic nonbacterial prostatitis (CNP) at different time points of modeling.

METHODSForty adult male SD rats were randomly divided into four groups of equal number, control, 45 d model, 60 d model, and 90 d model, and proteins were obtained from the prostatic tissue of another 30 rats. The CNP model was made by intraperitoneal injection of 0.5 ml DPT vaccineand intradermal injection of mixed solution of 1 ml prostatein extract and complete adjuvant at a 1∶1 ratio, while the control rats were injected with the same volume of normal saline. At 45, 60, and 90 days after modeling, we measured the paw withdrawal threshold (PWT) of the rats, determined the levels of TNF-α, IL-1β, IL-2, and IL-10 in the prostate tissue by ELISA, observed the histomorphological changes in the prostate by transmission electron and light microscopy, and detected the expressions of SP and NK1-R in the L5－S2 spinal cord by immunohistochemistry.

RESULTSThe model rats showed significantly increased sensitivity to pain, with remarkably lowered PWT at 45, 60, and 90 days after modeling. The levels of TNF-α, IL-1β, IL-2, and IL-10 in the prostate tissue were markedly elevated in the CNP models as compared with those in the controls (all P<0.05), most significantly at 90 days (all P<0.05). Immunohistochemistry showed that the expressions of SP and NK-1R were remarkably higher in the CNP model groups than in the control (all P<0.05), the highest at 90 days. Light microscopy revealed no inflammatory cell infiltration in the prostate tissue of the control rats, and obvious edema and increased lymphocytes were observed with the prolonged time of modeling.Transmission electron microscopy showed inflammatory changes in the prostate tissue of the model rats and that peritubular interstitial edema was most obvious at 90 days, with widened intervals between peritubular cells and the epithelial base and increased numbers of fibroblasts and collagen fibrils.

CONCLUSIONSThe synthesis of SP and the level of NK-1R were increased in the posterior horn of the L5－S2 spinal cord in the rat model of CNP.

Animals ; Interleukin-10 ; metabolism ; Interleukin-1beta ; metabolism ; Interleukin-2 ; metabolism ; Male ; Pain ; Prostatitis ; metabolism ; physiopathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Neurokinin-1 ; metabolism ; Spinal Cord ; metabolism ; Substance P ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo observe the expressions of the substance P (SP) mRNA and neurokinin-1 receptor (NK-1R) in the posterior horn of the L5 - S2 spinal cord in the rat model of chronic prostatitis pain, and to investigate the changes in the activation of astrocytes and influence of SP on this activation in rat spinal cord astrocytes cultured in vitro.

METHODSThe rat model of chronic prostatitis pain was established by injection of complete Freund's adjuvant (CFA) and assessed by the tail flick threshold test, the control rats injected with sodium chloride and all observed at 0, 14 and 28 days. Changes in the expressions of SP mRNA, NK-1R, glial fibrillary acidic protein (GFAP), tumor necrosis factor-alpha (TNF-alpha) and inducible nitric oxide synthase (iNOS) in the posterior horn of the L5 - S2 spinal cord were detected by RT-PCR and Western blot. Rat spinal cord astrocytes were cultured in vitro and divided into a control group, cultured with ITS cell culture fluid, and two experiment groups, with Group 1 stimulated with SP at the concentration of 10(-9) - 10(-6) mol/L for 12 hours followed by determination of the expressions of TNF-alpha, IL-1beta, NO and NOS by ELISA and nitrate reductase and colorimetric methods, and Group 2 at 10(-7) mol/L for 0, 24, 48 and 72 hours followed by detection of the GFAP expression by Western blot.

RESULTSThe expressions of SP mRNA, NK-1 R, GFAP, TNF-alpha and iNOS in the posterior horn of the L5 - S2 spinal cord were obviously higher in the rat prostatitis pain models than in the controls, successively higher at 28 than at 14 and 0 d (P < 0.01), and so was the expression of GFAP at 28 than at 14 d in the experiment groups (P < 0.05). SP induced a gradual increase at 10(-7) mol/L in the expression of GFAP in the spinal cord astrocytes at 0 -72 h, significantly different from that of the control group (P < 0.01), and it promoted the excretion of TNF-alpha and IL-1beta and the activity of NO and NOS at 10(-9) - 10(-6) mol/L at 12 h in a concentration-dependent manner, with marked differences between the experiment and control groups (P < 0.01, P < 0.05). But a decreased excretion of IL-1 beta was observed in the 10(-6) mol/L group, though with no significant difference from the control (P > 0.05).

CONCLUSIONChronic prostatitis pain could upregulate the expressions of the excitatory transmitter SP and receptor in the L5 - S2 spinal cord, and result in the activation of astrocytes and increased excretion of proinflammatory cytokines, which may be associated with the persistence and generalization of prostatitis pain.

Animals ; Astrocytes ; metabolism ; Chronic Disease ; Male ; Nitric Oxide Synthase Type II ; metabolism ; Pain ; metabolism ; Prostatitis ; metabolism ; Rats ; Receptors, Neurokinin-1 ; metabolism ; Spinal Cord ; cytology ; metabolism ; pathology ; Substance P ; metabolism

OBJECTIVE: To discuss the treatment of H3R agonist, IMETIT, on the allergic rhinitis(AR) ,and the influence to mRNA of Substance P(SP) and Substance P Receptor (SP-R) in AR model of guinea pigs. METHOD: The severity of AR was assessed by allergic symptoms (sneezing, nasal rubbing and nose blocking). The changes in the nasal mucosa were studied by pathological methods. The expression of SP positive cell was detected by immunohistochemistry, and the expression of SP-R mRNA was detected by reverse transcriptive polymerase chain reaction (RT-PCR). RESULT: Histamine H3R agonists, IMETIT can effectively improve the AR symptoms, sneezing, nasal itching, nasal congestion, reduce the pathological changes in the nasal mucosa, cut down the SP secretion and SP-R mRNA expression. CONCLUSION Histamine H3R agonist, IMETIT can effectively relieve the symptoms of AR in guinea pigs, which is related to reducing SP secretion and SP-R mRNA expression.
Animals ; Female ; Guinea Pigs ; Imidazoles ; therapeutic use ; Male ; Receptors, Histamine H3 ; drug effects ; Receptors, Neurokinin-1 ; genetics ; metabolism ; Rhinitis, Allergic, Perennial ; drug therapy ; metabolism ; Substance P ; metabolism ; Thiourea ; analogs & derivatives ; therapeutic use

To investigate the effect of cetirizine hydrochloride on the expression of neurokinin 1 receptor (NK-1R) and cytokines production induced by substance P (SP) in HaCaT cells (a human epidermal keratinocyte cell line) and dermal fibroblasts. The effect of cetirizine on the expression of NK-1R protein was detected by flow cytometry and Western blotting analysis. The modulation of cetirizine on the production of interferon (IFN)-gamma, interleukin (IL)-1beta, IL-6 and IL-8 in HaCaT cells and fibroblasts was measured by ELISA. The results showed that cetirizine significantly inhibited the expression of NK-1R in HaCaT cells and fibroblasts. SP induced the production of IFN-gamma, IL-1beta and IL-8 in both cell types. Cetirizine 1-100 micromol x L(-1) inhibited SP-induced IL-1beta and IL-8 production in HaCaT cells and fibroblasts, while had no effect on the production of IFN-gamma in both cells. Both SP and cetirizine had no effect on the secretion of IL-6 in HaCaT cells and fibroblasts. These findings suggest that cetirizine may be involved in the treatment of SP-induced skin inflammation by inhibiting the expression of substance P receptor and regulation the production of IL-1beta and IL-8 in epidermal keratinocyte and dermal fibroblasts.
Anti-Allergic Agents ; pharmacology ; Cell Line ; Cetirizine ; pharmacology ; Fibroblasts ; cytology ; metabolism ; Histamine H1 Antagonists, Non-Sedating ; pharmacology ; Humans ; Interferon-gamma ; metabolism ; Interleukin-1beta ; metabolism ; Interleukin-8 ; metabolism ; Keratinocytes ; cytology ; metabolism ; Receptors, Neurokinin-1 ; metabolism ; Substance P ; pharmacology

The aim of this study was to, from the point of neurogenic inflammation, explore the pathogenesis of colitis and to provide direct evidence for the neurogenic colitis hypothesis. Male Sprague-Dawley rats (180-220 g) anesthetized with chloral hydrate were intrathecally (ith) implanted with polyethylene-10 (PE-10) catheter to reach the spinal cord T₁₂-L₅ level. Substance P (SP) was ith injected once a day for 14 d. The disease active index (DAI) score was calculated by rat body weight and stool. The macroscopic and HE staining-microscopic pathologies of colon/spinal tissue were evaluated. By immunofluorescence staining, the protein expression of a pro-inflammatory cytokine, migration inhibitory factor (MIF), in colon tissue was detected and was semi-quantitatively analyzed. The results showed that in the colon tissue, inflammation was dose-dependently aggravated by ith SP 10 μ and 20 μ, whereas in the spinal tissue, only slight edema and congestion were seen in SP 20 μ group. The MIF protein of colon tissue was increased in ith SP 10 μ and 20 μ groups (P<0.05, P<0.01 as compared to normal saline group respectively), but in the spinal tissue, there was no obvious MIF protein expression either in SP groups or in normal saline group. Pretreatment with neurokinin-1 (NK₁) receptor antagonist ([D-Pro2, D-Trp7, 9] -SP, 22.4 μ, ith, 10 min before ith SP) prolonged the latency of DAI rising and reduced the DAI amplitude, as well as prevented the high MIF expression induced by ith SP. These results suggest that rat colitis can be induced by direct SP stimulation in lumbar spine via activating central NK₁ receptor; and that colonic MIF is possibly one of the inflammatory factors involved in this pathogenesis. These data provide a reasonable support to the hypothesis of colitis being a neurogenic inflammation. In addition, a potential clinical significance for the finding that higher concentration of spinal SP can induce colitis via NK₁ receptor is discussed.
Animals ; Colitis ; chemically induced ; Colon ; pathology ; Disease Models, Animal ; Inflammation ; pathology ; Injections, Spinal ; Intramolecular Oxidoreductases ; metabolism ; Macrophage Migration-Inhibitory Factors ; metabolism ; Male ; Neurokinin-1 Receptor Antagonists ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, Neurokinin-1 ; metabolism ; Spinal Cord ; pathology ; Substance P ; adverse effects

BACKGROUNDGingerol is the generic term for pungent constituents in ginger, which has been reported to be effective for inhibiting vomiting. We attempted to investigate the antiemetic effect of gingerol and its effective mechanism on substance P and NK(1) receptors in minks.

METHODSThe antiemetic effect of gingerol was investigated during a 6-hour observation on a vomiting model in minks induced by cisplatin, (7.5 mg/kg, intraperitoneal). The distribution of substance P and NK(1) receptors in the area postrema and ileum were measured by immunohistochemistry, and the expression of NK(1) receptor in the area postrema and ileum were measured by Western blotting.

RESULTSThe frequency of cisplatin induced retching and vomiting was significantly reduced by pretreatment with gingerol in a dose-dependent manner (P < 0.05). Substance P-immunoreactive was mainly situated in the mucosa and submucosa of the ileum as well as in the neurons of the area postrema. The immunoreactive production of NK(1) receptor was mainly situated in the muscular and submucosa of ileum and the neurons of area postrema, gingerol markedly suppressed the increased immunoreactivity of substance P and NK(1)1 receptor induced by cisplatin in a dose-dependent manner (P < 0.05), and exhibited effective inhibition on the increased expression levels of NK(1) receptor in both the ileum and area postrema dose-dependently (P < 0.05).

CONCLUSIONSGingerol has good activity against cisplatin-induced emesis in minks possibly by inhibiting central or peripheral increase of substance P and NK(1) receptors.

Animals ; Area Postrema ; metabolism ; Blotting, Western ; Catechols ; therapeutic use ; Disease Models, Animal ; Fatty Alcohols ; therapeutic use ; Ileum ; metabolism ; Immunohistochemistry ; Male ; Mink ; Receptors, Neurokinin-1 ; metabolism ; Substance P ; metabolism ; Vomiting ; chemically induced ; drug therapy

OBJECTIVETo investigate the effect of montelukast on the expression of sensory neuropeptide (neurokinin-1) receptor (NK1R) in young asthmatic rats with airway remodeling.

METHODSTwenty-four Sprague-Dawley rats were randomly divided into control group (n=8), asthma (n=8), and montelukast groups (n=8). A rat model of asthma was induced by ovalbumin (OVA) inhalation. Normal saline was used instead of sensitizing solution and 1% OVA in the control group. Each rat in the montelukast group was given montelukast (15 mg/kg) by gavage 2 h before OVA inhalation. All rats received their respective treatments for 8 weeks. Immunohistochemistry, real-time PCR and Western blot were used to measure the mRNA and protein expression levels of NK1R in asthmatic airway remolding and to evaluate the effect of montelukast on NK1R expression.

RESULTSThe asthma group showed significantly higher mRNA and protein expression levels of NK1R than the control group (P<0.01). The mRNA and protein expression levels of NK1R in the montelukast group were significantly lower than in the asthma group (P<0.05), but significantly higher than in the control group (P<0.01).

CONCLUSIONSRats with induced asthma have upregulated NK1R expression in the airway, and montelukast can downregulate NK1R expression during airway remodeling.

Acetates ; pharmacology ; Airway Remodeling ; drug effects ; Animals ; Anti-Asthmatic Agents ; pharmacology ; Asthma ; drug therapy ; metabolism ; Female ; Leukotriene Antagonists ; pharmacology ; Quinolines ; pharmacology ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptors, Neurokinin-1 ; analysis ; genetics