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1.
Abstract Nitric oxide (NO) plays an important physiological role in regulating gastrointestinal motility. Involvement of endogenous NO was evaluated in the response to non-adrenergic, non-cholinergic (NANC) nerve stimulation of the dog sphincter muscle of Oddi. Transmural electrical stimulation (TES), nicotine (10?5M) and K+ (10 mM) produced only a relaxation in the sphincter muscle strips contracted with substance P, which was not potentiated by atropine. The TES-induced relaxation was abolished by tetrodotoxin (3 times 10?7 M) and oxyhaemoglobin (1.6 times 10?5 M), but not affected by atropine (10?7 M), propranolol (10?7 M), phentolamine (10?7 M), indomethacin (10?6 M), chole-cystokinin (CCK, 10?8 M) and vasoactive intestinal polypeptide (VIP, 10?8 M). The relaxation was also abolished by treatment with NG-nitro-L-arginine (L-NA, 10?5 M), an NO synthase inhibitor. Nicotine produced a transient relaxation, which was abolished by tetrodotoxin, hexamethonium (10?5 M) and L-NA, but not affected by atropine and NG-nitro-D-arginine (D-NA, 10?5 M). The addition of K+ elicited a transient relaxation, which was abolished by tetrodotoxin and L-NA. The inhibitory effects of L-NA were antagonized by L-arginine (10?3 M). The presence of neurons containing nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase was histochemically demonstrated in the sphincter of Oddi. These findings may indicate that TES, nicotine and K+ liberate NO from NANC inhibitory nerve which is involved in the relaxation of the dog sphincter of Oddi. The muscular tone does not seem to be regulated by cholinergic nerves under the experimental conditions used. 相似文献
2.
Isao Hamamoto Shunichi Takaya Satoru Todo Oscar Bronsther Shiro Fujita Thomas M. Van Gulik Kenjiro Nakamura William Irish Thomas E. Starzl 《Transplant international》1994,7(2):89-95
Sixty-eight primary liver grafts were analyzed to see whether adenine nucleotides (AN: ATP, ADP, and AMP) or purine catabolites (PC: adenosine, inosine, hypoxanthine, and xanthine) of tissue or effluent can predict primary graft nonfunction. AN, PC, and nicotinamide adenine dinucleotide, oxidized form (NAD+) of the tissue before (pretransplant) and after graft reperfusion (post-transplant) and of the effluent were analyzed. The graft outcome was classified into two groups (group A: successful, n=64; group B: primary nonfunctioning, n=4). No significant differences were observed in pretransplant measurements between groups A and B, whereas ATP, ADP, total AN, total AN+total PC (T) and NAD+, in post-transplant tissues, were significantly higher in group A. Xanthine in the effluent was significantly higher in group B than in group A. ATP, ADP, total AN, T, and NAD+ in post-transplant tissue were significantly associated with primary graft nonfunction by logistic regression analysis. 相似文献
3.
W. Birkmayer G. J. D. Birkmayer K. Vrecko W. Mlekusch B. Paletta E. Ott 《Journal of neural transmission (Vienna, Austria : 1996)》1989,1(4):297-302
Summary The coenzyme nicotinamide adenine dinucleotide (NADH) has been used in an open label trial as novel medication in 34 patients with Parkinson's disease, using an intravenous administration technique. In all patients a beneficial clinical effect was observed. 21 patients (61.7%) showed a very good (better than 30%) improvement of disability, 13 patients (38.3%) a moderate (up to 30%) improvement. Concomitant with the improvement of the disability the urine level of homovanillic acid (HVA) increased significantly in all patients (in some patients by more than a 100%). The daily on phases of the patients could be increased from 2 up to 9 hours in the individual patients by NADH administration. 相似文献
4.
The action of continuous low-frequency vibration on rats for 1 month caused no changes in the total adenine nucleotides of the brain but led to a marked decrease in the ATP content and total adenine nucleotides in the limb muscles. After exposure to vibration for 3 months considerable exhaustion of the total adenine nucleotides of both muscles and brain was found. In the case of interrupted exposure to vibration the state of the adenine-nucleotide system depended on the duration of the pauses between periods of continuous exposure to vibration. During vibration with the shortest pauses (4 min) between successive periods of 30 min of vibration no changes were observed in the energy metabolism of the muscles and brain. Vibration with pauses of 8 and 15 min was found to be unfavorable for the adenine nucleotides of the muscles and vibration with a pause of 8 min for the brain.Kiev Institute of Work Hygiene and Occupational Diseases, (Presented by Academician of the Academy of Medical Sciences of the USSR L. I. Medved'.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 7, pp. 35–38, July, 1978. 相似文献
5.
6.
Ken Dewitte Marc Claeys Emeline Van Craenenbroeck Koen Monsieurs Hein Heidbuchel Vicky Hoymans Tibor Stoop 《Pathophysiology》2019,26(1):53-59
Aims
We explored the effect of remote ischaemic conditioning (RIC) on endothelial function and on circulating mediators.Methods and results
In 20 healthy male volunteers (mean age 31?±?10 years), flow-mediated dilation (FMD) was measured before and after 20?min of arm ischaemia, followed by reperfusion. Remote ischaemic conditioning (RIC) was performed by applying 3 cycles of 5?min of ischaemia of the leg at the onset of index arm ischaemia. Each volunteer underwent the IR-induced vascular injury protocol with and without RIC in a crossover study design.In the control group, IR significantly reduced FMD (5.9?±?2.9% before IR vs. 2.2?±?3.7% after IR; p?<?0.001). This effect was significantly attenuated by performing RIC (FMD of 5.5?±?3.1% before IR vs. 4.0?±?3.4% % after IR; p for interaction?=?0.01). Serum levels of SOD and ADMA increased significantly whereas MCP-1 and VEGF levels decreased significantly.Only changes in SOD levels were significantly related to the degree of RIC induced protection (r²?=?0.34; p?=?0.018).Conclusion
RIC has protective effects against endothelial IR injury. Our biomarker study suggests that anti-oxidative stress mediators, such as SOD, seem to be more involved in the pathogenesis of RIC-induced protection in humans than angiogenesis factors or chemo-attractant cytokines. 相似文献7.
Calretinin- and parvalbumin-immunoreactive neurons in the rat main olfactory bulb do not express NADPH-diaphorase activity 总被引:2,自引:0,他引:2
J. G. Brin J. R. Alonso E. García-Ojeda C. Crespo R. Arvalo J. Aijn 《Journal of chemical neuroanatomy》1997,13(4):253-264
The presence of nitric oxide synthase (NOS) in neuronal elements expressing the calcium-binding proteins calretinin (CR) and parvalbumin (PV) was studied in the rat main olfactory bulb. CR and PV were detected by using immunocytochemistry and the nitric oxide (NO) -synthesizing cells were identified by means of the reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase) direct histochemical method. The possible coexistence of NADPH-diaphorase and each calcium-binding protein marker was determined by sequential histochemical-immunohistochemical double-labeling of the same sections. Specific neuronal populations were positive for these three markers. A subpopulation of olfactory fibers and olfactory glomeruli were positive for either NADPH-diaphorase or CR. In the most superficial layers, groups of juxtaglomerular cells, superficial short-axon cells and Van Gehuchten cells demonstrated staining for all three markers. In the deep regions, abundant granule cells were NADPH-diaphorase- and CR-positive and a few were PV-immunoreactive. Scarce deep short-axon cells demonstrated either CR-, PV-, or NADPH-diaphorase staining. Among all these labeled elements, no neuron expressing CR or PV colocalized NADPH-diaphorase staining. The present data contribute to a more detailed classification of the chemically- and morphologically-defined neuronal types in the rodent olfactory bulb. The neurochemical differences support the existence of physiologically distinct groups within morphologically homogeneous populations. Each of these groups would be involved in different modulatory mechanisms of the olfactory information. In addition, the absence of CR and PV in neuronal groups displaying NADPH-diaphorase, which moreover are calmodulin-negative, indicate that the regulation of NOS activity in calmodulin-negative neurons of the rat olfactory bulb is not mediated by CR or PV. 相似文献
8.
目的 :研究S型与RS型二羟丙腺苷 (DHPA)与高压氧联用对人工感染小白鼠体内日本乙型脑炎 (乙脑 )病毒的抑制作用。方法 :整个实验用两株不同乙脑病毒分两次进行。每次一株 ,乙脑病毒接种小白鼠后将其分组 ,接种后 4~ 6h开始治疗 ,连续 5d ,于开始治疗后第二周末结束实验 ,计算每组小鼠死亡与存活数。结果 :对照组与 (S) DHPA/高压氧联合治疗组及 (RS) DHPA/高压氧联合治疗组效果差异有高度显著性 (P分别 <0 .0 2 5及 <0 .0 1) ,对照组与其他组治疗效果差异无显著性 (P均 >0 .0 5 )。结果 :(S) DHPA或 /及 (RS) DHPA与高压氧联合治疗可抑制人工感染小鼠体内日本乙型脑炎病毒的致病作用。 相似文献
9.
目的制备NAD亲和胶,用于分离纯化2,5-二酮基-D-葡萄糖酸还原酶。方法将NAD通过丁二酸二酰肼与溴化氰活化的Sepharose6MB胶联结,制得NAD亲和胶。从棒杆菌细胞中提取的2,5-二酮基-D-葡萄糖酸还原酶粗酶液用NAD亲和胶进行亲和层析纯化。结果NAD的结合率为71.67%;亲和层析回收率为77.27%;酶的比活提高了1.1倍。结论以NAD为配基的亲和胶用于纯化以NADPH为辅酶的2,5-DKG还原酶行之有效。 相似文献
10.
烟酰胺腺嘌呤二核苷酸磷酸氧化酶是心血管系统中活性氧(reactive oxygen species,ROS)的主要来源,它包
括7种亚型并分别表达在不同的心血管细胞及其细胞器中,参与调节细胞增殖、迁移、分化、凋亡、衰老和炎症反应
等多种活动,其衍生的ROS参与高血压、动脉粥样硬化、糖尿病血管病变、心肌梗死后心室重构等多种心血管疾病
的病理过程。 相似文献