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991.
The cloned capsaicin receptor, also known as vanilloid receptor subtype 1 (VR1) receptor, has been demonstrated to be an integral membrane protein with homology to a family of putative store-operated calcium channels. The VR1 receptor is activated not only by capsaicin but also by noxious heat and protons, and therefore it is suggested as a molecular integrator of chemical and physical stimuli that elicit pain. In the present study, indirect immunofluorescence detected a small number of neurons that are VR1 receptor immunoreactive (ir) (171 versus 1038 or 16% of all neuronal cell bodies) in the human trigeminal ganglion (TG). In addition, RT-PCR confirmed the presence of VR1 mRNA in the human TG. It has been hypothesized that TG neuronal cell bodies are the source of capsaicin-stimulated release of calcitonin gene-related peptide (CGRP), and hence co-localization experiments were performed. Around 10% of the VR1 receptor-ir is expressed on neurons that contain CGRP-ir (ten among 74) in the human TG, indicating that capsaicin may act through the VR1 receptor to modulate the release of CGRP and in turn to modulate pain. We observed that 8% of the VR1 receptor-ir neuronal cell bodies contain substance P-ir and 5% nitric oxide synthase. Capsaicin can release nitric oxide, CGRP and substance P from sensory nerves and contribute to central sensitization. 相似文献
992.
Peptide accumulations in proximal endbulbs of transected axons 总被引:2,自引:0,他引:2
Axons proximal to a transection develop into enlarged, but presumed 'passive' endbulb structures. In previous studies, we observed that proximal stumps of transected sciatic nerves accumulate discrete and striking deposits of calcitonin gene-related peptide (CGRP) that have apparent direct and local actions on nearby microvessels. In this work, we provide evidence that CGRP, in the company of several additional peptides, are deposited through 'arrested' anterograde transport into axon endbulbs that develop after transection. In proximal stump tips of rat sciatic nerves transected 48 h earlier, CGRP accumulation colocalized with a label for neurofilament that was accentuated at axon tips, but was prevented by a concurrent more proximal sciatic section. Similarly, interruption of CGRP deposition eliminated its apparent actions on local microvessels following injury. CGRP accumulation was also observed in sural nerve proximal stump tips, indicating its presence in sensory axons despite the known declines in the sensory neuronal synthesis of CGRP that occur following axotomy. Peptide accumulation was not unique to CGRP, with a similar pattern of anterograde accumulation observed for substance P (SP), neuropeptide Y (NPY) and galanin. Deposited peptides and perhaps other axonal constituents in the milieu of a peripheral nerve injury may be associated with important local physiological actions in the regenerative microenvironment. 相似文献
993.
高氧液对病毒性脑炎患儿脑脊液内皮素和降钙素基因相关肽的影响 总被引:10,自引:0,他引:10
目的 探讨高氧液对病毒性脑炎患儿脑组织保护作用的机制。
方法 以2004年1~12月武汉市儿童医院收治的40例病毒性脑炎患儿为研究对象,随机分为常规治疗组和高氧液治疗组(常规治疗+高氧液),治疗前后观察临床症状及脑影像学改善情况,并采用放射免疫法监测脑脊液内皮素(ET)和降钙素基因相关肽(CGRP)质量浓度变化。
结果 与常规组比较,高氧液组临床症状和脑影像学改变的消失时间以及住院时间明显缩短(P<0.05,P<0.01);ET、ET/CGRP比值降低和CGRP升高更为显著(P<0.05,P<0.01)。
结论 ①ET/CGRP比值失衡是导致病毒性脑炎发生、发展的重要因素;②高氧液通过改善脑组织供氧、恢复ET/CGRP动态平衡,从而发挥其保护作用。 相似文献
994.
995.
Summary Various doses of sodium fluoride (NaF), salmon calcitonin (CT) and NaF combined with CT were given intravenously to rats (236±2
g). Blood plasma samples were collected at various times up to 24 hours and measured for total calcium (adjusted for variation
in plasma albumin), inorganic phosphate, ionic fluoride, urea, and creatinine. Following injection of NaF alone, significant
hypocalcemia and hyperphosphatemia was observed. In contrast, CT injections resulted in hypocalcemia and hypophosphatemia.
NaF and CT given in combination generally resulted in the hypocalcemia being equal to or greater than that calculated from
the simple addition of their individual effects. Significant increases in both plasma creatinine and plasma urea were observed
following treatment with NaF alone or with CT and NaF together, whereas CT alone had negligible effect. These results suggest
that NaF does not mimic the effects of CT; rather that NaF and CT interact to modify their individual effects. The influence
of NaF probably occurs via an effect on kidney function. 相似文献
996.
可溶性细胞间黏附分子-1、降钙素原在新生儿败血症诊断中的价值 总被引:11,自引:0,他引:11
目的 了解可溶性细胞间黏附分子 1(sICAM 1)、降钙素原 (PCT)在新生儿败血症诊断中的价值。方法 通过检测 5 0例败血症的新生儿及 35例健康新生儿血sICAM 1、PCT、CRP浓度及WBC计数 ,比较各炎症指标对诊断败血症的灵敏度、特异度、阳性预测值、阴性预测值和准确性、约登指数 ,评价它们对诊断该病的价值。结果 (1)以sICAM 1≥ 30 0ng/ml、CRP≥ 8mg/l、PCT≥ 2ng/ml为阳性标准 ,三指标对诊断败血症的灵敏度分别为 85 %、87 5 %、86 % ,P >0 0 5 ,差异无显著意义 ,但均高于WBC计数 (仅 30 % ,P <0 0 5 ) ,其中PCT的特异度 94 3%、阳性预测值 95 6 %、阴性预测值82 5 %、准确性 89 4 %、约登指数 80 3% ;(2 )sICAM 1浓度在治疗前后差异无显著意义 ,P >0 0 5 ;CRP浓度在两组差异有显著意义 ,P <0 0 5 ;PCT在恢复期全部转阴 ;(3)sICAM 1与CRP呈正相关 ,r =0 339,P <0 0 1;PCT与sICAM 1、CRP浓度的等级相关系数分别为 0 5 6 9、0 4 82 (P <0 0 1)。结论 sICAM 1≥ 30 0ng/ml对于诊断新生儿败血症是一个具有较高灵敏度 (85 % )、中度特异度 (5 4 3% )的指标 ;所有检测指标中PCT特异度、阳性预测值、阴性预测值、准确性、约登指数最高 相似文献
997.
Nishiki K Tsuruoka S Wakaumi M Yamamoto H Koyama A Fujimura A 《European journal of pharmacology》2003,460(2-3):171-175
Dosing time-dependent variation in the hypocalcemic effect of salmon calcitonin was examined in rats under a 12-h light–dark cycle. In both a single-dosing study with normal rats and a repeated-dosing study with hypercalcemic rats (induced by chronic vitamin-D dosing), we consistently observed that the hypocalcemic effect of calcitonin was greater when the drug was given at 14 h after lights on than that at 2 h after lights on. The reduction in urinary deoxypyridinoline excretion, a marker of bone resorption, was also greater when calcitonin was given at 14 h after lights on. Urinary excretion of Ca was not affected by the drug. Pharmacokinetic profiles of calcitonin after a single dosing did not differ between the two trials. These results indicate that the hypocalcemic effect of calcitonin is greater after dosing in the early dark phase (14 h after lights on) than after dosing in the early light phase (2 h after lights on). A time-dependent variation in the sensitivity to the drug of osteoclasts, but not renal tissues, may be involved in the mechanism of this event. 相似文献
998.
Involvement of calcitonin gene-related peptide in the depressor effects of losartan and perindopril in rats 总被引:12,自引:0,他引:12
Previous investigations have indicated that calcitonin gene-related peptide (CGRP) plays an important role in the regulation of cardiovascular function, and that the development of hypertension may be related to the reduction of sensory vasodilator nerve actions. In the present study, we examined the effect of perindopril, an angiotensin-converting enzyme inhibitor, and losartan, an angiotensin II receptor antagonist, on the plasma level and synthesis of CGRP in 2 kidneys, 1-clip hypertensive rats (2K1C, Goldblatt). In the hypertension group, systolic blood pressure and mean artery pressure were raised, and the level of CGRP in plasma was slightly raised compared with control groups. Chronic treatment with losartan or perindopril significantly increased the plasma concentration of CGRP and the expression of CGRP mRNA in dorsal root ganglia in the 2K1C, Goldblatt hypertensive rats. These results suggest that the 2K1C, Goldblatt hypertensive model has a compensatory increase of sensory nerve actions, and that the depressor effects of perindopril or losartan may be related to stimulation of the synthesis and release of CGRP in the 2K1C, Goldblatt hypertensive rats. 相似文献
999.
目的 分析慢性肺心病 (CCP)急性加重期不同心功能血浆内皮素 1(ET 1)、一氧化氮 (NO)和降钙素基因相关肽 (CGRP)的含量。方法 分别测定CCP患者急性加重期心功能Ⅲ~Ⅳ级 (A组 ) 2 8例、Ⅱ级(B组 ) 16例和健康对照组 (C组 ) 30例的ET 1、NO和CGRP的血浆含量。结果 ET 1血浆含量A组、B组和C组分别是 6 1 87± 2 3 33ng/L、5 3 84± 2 0 83ng/L和 39 0 4± 2 0 36ng/L ,A组与C组和B组与C组比较 ,差异有非常显著意义和显著意义 ,而A组与B组比较 ,差异无显著意义 (P >0 0 5 ) ;NO血浆含量A组、B组和C组分别是 75 6 8± 2 2 17μmol/L、6 0 89± 4 2 74 μmol/L和 5 0 2 6± 18 2 5 μmol/L ,A组与C组比较 ,差异有非常显著意义 ,而A组与B组和B组与C组比较 ,差异均无显著意义 (P均 >0 0 5 ) ;CGRP血浆含量A组、B组和C组分别是 71 38± 2 7 70ng/L、6 0 30± 38 5 8ng/L和 39 5 7± 15 75ng/L ,A组与C组和B组与C组比较 ,差异有非常显著意义和显著意义 ,而A组与B组比较 ,差异无显著意义 (P >0 0 5 )。结论 CCP急性加重期心功能Ⅲ~Ⅳ级时、血浆ET 1、NO和CGRP含量均增高 ,Ⅱ级时ET 1和CGRP增高 ;心功能Ⅲ~Ⅳ级和Ⅱ级之间 ,ET 1和CGRP的增高无不同 相似文献
1000.