Study on expression and change of CRLR, CGRP-RCP in venous blood of New Zealand rabbit with allergic rhinitis / 重庆医学

Objective To observe the expressions and change of calcitonin receptor-like receptor(CRLR) and calcitonin generelated peptide receptor component protein(CGRP-RCP)in venous blood of New Zealand rabbit with allergic rhinitis and to analyze its effective mechanism.Methods Twenty-four New Zealand rabbits were divided into the normal control group(A) and allergic rhinitis group(B).Ovalbumin was used to immunize New Zealand rabbits and conduct the nasal cavity stimulation for preparing allergic rhinitis model.The rabbit behavior change was observed in the two groups.The turbinate and nasal septum mucosa were taken for preparing HE sections.The pathologic change of nasal mucosa was observed.The venous blood was collected for detecting CRLR and CGRP-RCP levels change by ELISA.Results The behavior scores showed that the behavior score on 1-5 d after nasal cavity stimulation had statistical difference between the two groups(P＜0.05).The HE staining displayed that the nasal cavity mucosa and mesenchyma had slightly edema with blood vessels mild hyperplasia and congestion,the inflammatory cells infiltration was unobvious,and had little nasal secretions.The group B had obvious interstitial edema,vascular hyperplasia,congestion and a large number of eosinophils and other inflammatory cells infiltration.The CRLR and CGRP-RCP levels in the group B were significantly increased compared with the group A(t=5.143,10.595,P＜0.05).Conclusion CRLR and CGRP-RCP may play an important effect in pathogenesis of allergic rhinitis.

Study on expression and change of CRLR, CGRP-RCP in venous blood of New Zealand rabbit with allergic rhinitis / 重庆医学

Objective To observe the expressions and change of calcitonin receptor-like receptor(CRLR) and calcitonin generelated peptide receptor component protein(CGRP-RCP)in venous blood of New Zealand rabbit with allergic rhinitis and to analyze its effective mechanism.Methods Twenty-four New Zealand rabbits were divided into the normal control group(A) and allergic rhinitis group(B).Ovalbumin was used to immunize New Zealand rabbits and conduct the nasal cavity stimulation for preparing allergic rhinitis model.The rabbit behavior change was observed in the two groups.The turbinate and nasal septum mucosa were taken for preparing HE sections.The pathologic change of nasal mucosa was observed.The venous blood was collected for detecting CRLR and CGRP-RCP levels change by ELISA.Results The behavior scores showed that the behavior score on 1-5 d after nasal cavity stimulation had statistical difference between the two groups(P＜0.05).The HE staining displayed that the nasal cavity mucosa and mesenchyma had slightly edema with blood vessels mild hyperplasia and congestion,the inflammatory cells infiltration was unobvious,and had little nasal secretions.The group B had obvious interstitial edema,vascular hyperplasia,congestion and a large number of eosinophils and other inflammatory cells infiltration.The CRLR and CGRP-RCP levels in the group B were significantly increased compared with the group A(t=5.143,10.595,P＜0.05).Conclusion CRLR and CGRP-RCP may play an important effect in pathogenesis of allergic rhinitis.

Association of the single nucleotide polymorphisms in the calcitonin receptor-like receptor gene with primary angle closure in a Han Chinese population / 国际眼科杂志(Guoji Yanke Zazhi)

?AIM: To study the association of the single nucleotide polymorphism ( SNP) rs1157699 in the calcitonin receptor-like receptor ( CRLR ) gene with primary angle closure ( PAC) in a Han Chinese population.?METHODS: All samples, involved 232 PAC cases and 306 controls, were obtained from an epidemiologic survey conducted in Funing, Jiangsu Province, China. Genotyping were carried out by TaqMan-MGB probe using the real time quantitative polymerase chain reaction system to study the relationship between SNP of rs1157699 in CRLR gene and PAC.?RESULTS: The prevalence of CRLRrs1157699 genotype was 67.4%, 30.0%, 2.6% for CC, CT, TT in cases, and 71.3%, 27.0%, 1.7% in controls respectively.There was no difference between the two groups in the distribution of genotype and allele frequencies of rs1157699 (P>0.05).?CONCLUSION:Our results do not support a significant role for rs1157699 in CRLR with PAC.

Pharmacological characterization of the relaxant effect induced by adrenomedullin in rat cavernosal smooth muscle

The aim of the present study was to determine the mechanisms underlying the relaxant effect of adrenomedullin (AM) in rat cavernosal smooth muscle (CSM) and the expression of AM system components in this tissue. Functional assays using standard muscle bath procedures were performed in CSM isolated from male Wistar rats. Protein and mRNA levels of pre-pro-AM, calcitonin receptor-like receptor (CRLR), and Subtypes 1, 2 and 3 of the receptor activity-modifying protein (RAMP) family were assessed by Western immunoblotting and quantitative real-time polymerase chain reaction, respectively. Nitrate and 6-keto-prostaglandin F1α (6-keto-PGF1α; a stable product of prostacyclin) levels were determined using commercially available kits. Protein and mRNA of AM, CRLR, and RAMP 1, -2, and -3 were detected in rat CSM. Immunohistochemical assays demonstrated that AM and CRLR were expressed in rat CSM. AM relaxed CSM strips in a concentration-dependent manner. AM22-52, a selective antagonist for AM receptors, reduced the relaxation induced by AM. Conversely, CGRP8-37, a selective antagonist for calcitonin gene-related peptide receptors, did not affect AM-induced relaxation. Preincubation of CSM strips with NG-nitro-L-arginine-methyl-ester (L-NAME, nitric oxide synthase inhibitor), 1H-(1,2,4)oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, quanylyl cyclase inhibitor), Rp-8-Br-PET-cGMPS (cGMP-dependent protein kinase inhibitor), SC560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethyl pyrazole, selective cyclooxygenase-1 inhibitor], and 4-aminopyridine (voltage-dependent K+ channel blocker) reduced AM-induced relaxation. On the other hand, 7-nitroindazole (selective neuronal nitric oxide synthase inhibitor), wortmannin (phosphatidylinositol 3-kinase inhibitor), H89 (protein kinase A inhibitor), SQ22536 [9-(tetrahydro-2-furanyl)-9H-purin-6-amine, adenylate cyclase inhibitor], glibenclamide (selective blocker of ATP-sensitive K+ channels), and apamin (Ca2+-activated channel blocker) did not affect AM-induced relaxation. AM increased nitrate levels and 6-keto-PGF1α in rat CSM. The major new contribution of this research is that it demonstrated expression of AM and its receptor in rat CSM. Moreover, we provided evidence that AM-induced relaxation in this tissue is mediated by AM receptors by a mechanism that involves the nitric oxide-cGMP pathway, a vasodilator prostanoid, and the opening of voltage-dependent K+ channels.

Research progress of the pathophysiological role of receptor activity modifying proteins / 国际生物医学工程杂志

Receptor activity modifying proteins (RAMPs) is a kind protein with transmembrane functionality.RAMPs can interact with TypeⅡ G protein coupled receptors (GPCRs) such as calcitonin gene-related peptide receptor (CGRPR),calcitonin receptor (CTR) and calcitonin receptor-like receptor (CRLR),to form a stable heterodimer expression on the cell membrane.Different RAMPs can combine with CRLR or CTR to produce different receptor phenotypes with ligand-specific affinity and thus can decide biological effect of the receptors.In addition,RAMPs can also interact with other GPCRs,which promise broader application in function regulation of G-proteincoupled receptor of RAMPs'.RAMPs' regulation of GPCRs depends on its molecular basis.Our studies of RAMPs provides a new perspective to further researches on GPCRs functionality and CGRP signal transduction.

Effects of continuous intermedin infusion on blood pressure and hemodynamic function in spontaneously hypertensive rats / 老年心脏病学杂志（英文版）

Objective To examine the effects of exogenously administered intermedin (IMD,adrenomedullin-2) on arterial blood pressure,cardiac function and the cardiovascular IMD receptor system in spontaneously hypertensive rats (SHRs) as well as to investigate the associated mechanisms.Methods Thirteen week-old male rats were divided in Wistar Kyoto (WKY) group (n =12),SHR group (n =12),IMD group (SHRs infused with IMD 1-47 500 ng/kg per hour,n =12),and ADM group (SHRs infused with adrenomedullin 500 ng/kg per hour,n =12).Results A two-week continuous administration of low dose IMD 1-47 via mini-osmotic pumps markedly reduced blood pressure,the maximal rates of increase and decrease of left-ventricle pressure development (LV ± dp/dtmax),left ventricular systolic pressure and heart rate in SHRs.Furthermore,IMD also inhibited protein over-expression of cardiovascular IMD receptors,myocardial Receptor Activity-Modifying Proteins (RAMP1 and RAMP2),aortic RAMP1,RAMP2,RAMP3,and calcitonin receptor-like receptor (CRLR);suppressed up-regulation of aortic RAMP1,RAMP2,RAMP3 and CRLR gene expression; and markedly elevated the mRNA abundance of myocardial atrial natriuretic peptide (ANP) and myocardial brain natriuretic peptide (BNP).Additionally,IMD 1-47 administration in SHRs increased aortic cAMP concentration and reduced myocardial cAMP concentration.Conclusion These findings support the speculation that IMD,as a cardiovascular active peptide,is involved in blood pressure reduction and cardiac function amelioration during hypertension.The mechanism underlying this effect may involve IMD binding of a receptor complex formed by RAMPs and CRLR,and consequential regulation of cAMP levels and other cardiovascular active factors,such as ANP and BNP.

Protect effect of Intermedin_(1-53) on isoproterenol-induced ischemic injury in rats heart / 中国药理学通报

Aim Observe the effects of IMD_ 1-53 on acute myocardial injury induced by isoproterenol (ISO). Methods Myocardial ischemia injury in rats was induced by subcutaneous injection with ISO(50 mg?kg -1?d -1, 2days ), and the therapeutic effect of IMD_ 1-53 was observed. Cardiac function was measured. Myocardial cAMP content was determined by radioimmunoassay (RIA). The gene expression of calcitonin receptor-like receptor (CL) and receptor-activity-modifying protein (RAMP1), RAMP2 and RAMP3 in ventricular was determined by semi-quantitative RT-PCR analysis. IMD receptors in cardiac sarcolemmal membrane fractions were assayed [ 125I]-IMD binding studies. Results ISO-treated rats showed lower maximal rate of increase and decrease of left-ventricle pressure development (?LVdp/dt_ max) and higher left-ventricle end-diastolic pressure (LVEDP; all P