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排序方式: 共有412条查询结果,搜索用时 15 毫秒
1.
淫羊藿苷对家兔阴茎海绵体的舒张作用及机制   总被引:1,自引:0,他引:1  
目的 观察淫羊藿苷 (ICA)对家兔阴茎海绵体平滑肌的舒张效应及机制。方法 采用离体平滑肌张力记录法。结果 ①淫羊藿苷、西地那非 (sildenafil,Sil)、罂粟碱 (Pap)及氨力农 (amrinone ,Amr)均可浓度依赖性地引起舒张效应 ,EC50 分别为 0 2 ,11 2 ,31 6和 5 0 1μmol/L。②NO合酶抑制剂N 硝基左旋精氨酸甲酯 (L NAME ) 5μmol/L可将ICA引起的最大舒张效应由 6 0 %降低到 9% ,而NO前体左旋精氨酸 (L Arginine) 2 0 μmol/L ,可部分恢复ICA的最大舒张效应到 4 0 % (P <0 0 5 )。③ICA (1,10 μmol/L)增强Ach引起的舒张效应 ,最大效应由 6 0 %分别升高到 6 7%和 80 % (P <0 0 5 )。④ICA (3,10 μmol/L)能使高K (2 0~ 12 0mmol/L)去极化引起的最大收缩反应分别降低到 88%和 81% (P <0 0 5 )。⑤在经 1μmol/L阿托品和 5 μmol/L胍乙啶预先处理的标本上 ,电场刺激可以引起海绵体平滑肌频率依赖性的舒张效应。ICA (1、 10 μmol/L)能增强电场刺激引起的舒张效应 ,最大效应由对照水平的4 1%分别升高到 5 9%和 6 3% (P <0 0 5 )。结论 ICA可以直接舒张阴茎海绵体平滑肌 ,其壮阳作用机制与影响NO cGMP信号通路有关。  相似文献   
2.
The relaxant effects of electrical field stimulation (EFS) and exogenously applied acetylcholine (ACh) or acidified NaNO2 (a-NaNO2) were investigated in the isolated mouse corpus cavernosum precontracted with phenylephrine hydrochloride (PE). Tetrodotoxin (TTX) blocked the relaxant effects of EFS completely, whereas it had no effect on the responses to ACh or a-NaNO2. Guanethidine and indomethacin failed to affect the electrically or ACh-induced relaxations. Atropine completely blocked the effect of ACh; however, it caused a slight reduction in the relaxation evoked by EFS.N G- Nitro-l-arginine (l-NOARG) reduced the effects of EFS and ACh significantly, but it was ineffective on the relaxations induced by a-NaNO2. The inhibitory action ofl-NOARG was partly restored byl-arginine, but not byd-arginine. Methylene blue (MB) and hydroxocobalamin (HC) exhibited significant inhibition on the relaxations evoked by EFS, ACh and a-NaNO2. Hydroquinone (HQ) reduced relaxation due to a-NaNO2, but did not affect that of EFS and ACh. Our findings suggest that EFS-induced relaxations of mouse cavernosal tissue are mediated by a transmitter which probably resembles an organic nitrate.  相似文献   
3.
The distribution of immunoreactivity (IR) for the neuropeptide vasoactive intestinal polypeptide (VIP) and neuronal nitric oxide synthase (nNOS) in the bovine retractor penis muscle (RP) and penile artery (PA) was studied by using two different methods. The distribution of these immunoreactivities was also compared with that of the immunoreactivity for cyclic guanosine monophosphate (cGMP). In both tissues the nerve fibers and terminals immunoreactive for VIP had a distribution that was completely different from that of the nerve fibers and terminals immunoreactive for nNOS. This contrasts with the previous observations in penile smooth muscle of other species. In the RP, as well as in the PA, many of the VIP-IR fibers were also immunoreactive for neurofilaments (NF), whereas the nNOS-IR fibers were consistently devoid of NF-IR. Stimulation with sodium nitroprusside, a nitric oxide donor, considerably increased cGMP-IR in the smooth muscle cells in both RP and PA, and in several nerve fibers in PA. Many of these cGMP-IR nerve fibers exhibited nNOS-IR, whereas none of them was immunoreactive for VIP. Our results suggest that the degree of coexistence of VIP-IR and nNOS-IR in the nerve fibers and terminals innervating penile smooth muscle show wide species differences. They also suggest that the mechanisms by which VIP could be involved in neurogenic penile erection may vary between species.  相似文献   
4.
The possible involvement of nitric oxide in the prevention by morphine of apomorphine- and oxytocin-induced penile erection and yawning was investigated by measuring the concentration of NO2- and NO3- in the dialysate obtained with a vertical microdialysis probe implanted in the paraventricular nucleus of the hypothalamus of male rats. Either apomorphine (80 μg/kgs.c.) or oxytocin (30 ng i.c.v.) increased significantly basal NO2- and NO3- concentration in the paraventricular dialysate, penile erection and yawning. Morphine (1, 5 and 10mg/kg i.p.) prevented dose-dependently either apomorphine or oxytocin responses when given 15min before apomorphine or oxytocin. Prevention by morphine of apomorphine and oxytocin responses was abolished by naloxone (3mg/kg i.p.) given 15min before morphine. Morphine prevented apomorphine and oxytocin responses also when given in the lateral ventricles or directly in the paraventricular nucleus. In contrast, the selective agonist of the kappa opioid receptor subtype U-69,593 was found to be ineffective. The present results confirm previous findings showing that morphine acts through μ receptors in the paraventricular nucleus to prevent apomorphine and oxytocin-induced penile erection and yawning and suggest that this morphine effect is mediated by a decreased activity of nitric oxide in the paraventricular nucleus of the hypothalamus. Received: 30 September 1996 / Accepted: 24 January 1997  相似文献   
5.
The aim of this paper was to establish if duplex ultrasound parameters obtained for assessment of the patency of cavernosal arteries in the penile flaccid state can give sufficient clinical information without the use of intracavernosal injection of vasodilatory drugs. We assessed mean cavernosal peak systolic velocity (PSV) in the penile flaccid state (basal PSV), and after PGE1 injection (dynamic PSV) in 339 unselected patients with erectile dysfunction. In 55 of these patients the waveform acceleration in the flaccid state was also assessed. The results of the study can be summarized as follows: (1) a significant relationship was found between basal and dynamic PSV in the 339 patients (r=0.477; p < 0.0001); (2) a basal PSV >12.5 cm/sec was predictive of a dynamic PSV >/=30 cm/sec in 129/139 (92.8%) of the patients, whereas in patients with a basal PSV or <30 cm/sec could be found; and (3) an acceleration >1 m/sec2 in the flaccid state was coupled to a dynamic PSV >30 cm/sec in 43/46 (93.5%) of the patients independent of the basal PSV. In conclusion, these results suggest that the combined duplex ultrasound assessment of PSV and waveform acceleration in the penile flaccid state can predict arterial dynamic inflow in the majority (51/55; 92.7%) of patients with erectile dysfunction, with less time and expense and less discomfort for the patient.  相似文献   
6.
Factors predicting recovery of erections after radical prostatectomy   总被引:19,自引:0,他引:19  
PURPOSE: Because preservation of functioning penile erections is a major concern for many patients considering treatment for localized prostate cancer, we analyzed various factors determined before and after radical retropubic prostatectomy to identify those significantly associated with recovery of erectile function. MATERIALS AND METHODS: Our prospective database of patients undergoing pelvic lymphadenectomy and radical retropubic prostatectomy was used to determine factors predictive of erection recovery after radical prostatectomy. The study included 314 consecutive men with prostate cancer treated with radical retropubic prostatectomy between November 1993 and December 1996. Preoperative potency satisfactory for intercourse and degree of neurovascular bundle preservation during the operation were documented. RESULTS: Patient age, preoperative potency status and extent of neurovascular bundle preservation but not pathological stage were predictive of potency recovery after radical prostatectomy. At 3 years after the operation 76% of men younger than age 60 years with full erections preoperatively who had bilateral neurovascular bundle preservation would be expected to regain erections sufficient for intercourse. Compared to the younger men, those 60 to 65 years old were only 56% (95% confidence interval [CI] 37 to 84) and those older than 65 years were 47% (95% CI 30 to 73) as likely to recover potency. Patients with recently diminished erections were only 63% (95% CI 38 to 100) as likely to recover potency as men with full erections preoperatively, and those with partial erections were only 47% (95% CI 23 to 96) as likely to recover potency. Resection of 1 neurovascular bundle reduced the chance of recovery to 25% (95% CI 10 to 61) compared to preserving both nerves. CONCLUSIONS: Knowledge of preoperative erectile function and patient age before the operation and the degree of neurovascular bundle preservation afterward may aid in patient counseling regarding potency recovery after radical prostatectomy.  相似文献   
7.
老年人勃起功能障碍的药物治疗进展   总被引:3,自引:0,他引:3  
阴茎勃起功能障碍(ED)的药物治疗主要有三类:①阴茎海绵体注射;②尿道局部给药;③口服药物。以西地那非为代表的磷酸二酯酶抑制剂因口服疗效好、不良事件少、使用方便、耐受性好而被广为使用,已成为一线治疗药物。伐地那非作用更强,他达那非持续作用更长。  相似文献   
8.
目的 对壮阳药效评价方法进行优化,以探求更为有效的候选药物筛选方法.方法 模型组大鼠均灌胃给予西地那非10 mg/kg,对照组大鼠给予相同容量的生理盐水灌胃,每天1次,连续灌胃给药14 d.每次给药后连续记录2h内大鼠阴茎勃起、阴部理毛、爬背次数和参与动物数,并计算PEI值.采用改良的壮阳药效评价方法,整个过程采用摄像头观察并在不同时间段给予雌鼠诱导.结果 在雌鼠诱导组中,模型组大鼠给药后2 h PEI值较对照组明显升高(P<0.05).在模型组中,与人为观察组相比,摄像头观察组大鼠给药后2 h PEI值明显升高(P<0.05);与非雌鼠诱导组相比,雌鼠诱导组大鼠给药后2 h PEI值明显升高(P<0.05);与持续诱导组相比,间断诱导组2h PEI值无明显差异,但60 ~ 120 min时间段PEI值明显升高(P<0.05).结论优化后的壮阳药效评价方法能更为有效的评价候选药物的壮阳药效.  相似文献   
9.
目的:评价每日小剂量他达拉非治疗骨盆骨折尿道断裂(PFUD)后勃起功能障碍(ED)的疗效。方法:2008年1月至2011年12月共有46例骨盆骨折尿道断裂后ED患者纳入观察。患者年龄25~51(33.9±7.2)岁,受伤时间3~72(19.6±12.7)个月。所有患者自诉受伤前的性功能正常。患者在未服用5型磷酸二酯酶抑制剂的情况下进行夜间勃起周径和硬度测量(NPTR)。根据NPTR检测结果将患者分为有夜间勃起异常组和无夜间勃起组。对所有患者给予每晚他达拉非10 mg治疗3个月,采用IIEF-5评分、性生活日记问题2和问题3评价治疗效果。结果:38例(82.6%)患者完成检查和治疗,8例失访。NPTR检测证实夜间勃起异常26例(68.4%),无夜间勃起12例(31.6%)。他达拉非治疗3个月后,夜间勃起异常组患者IIEF-5改善明显高于无夜间勃起组(P<0.05),夜间勃起异常组患者对SEP2和SEP3回答"是"的比例明显高于无夜间勃起组(76.9%vs41.7%,65.4%vs 25.0%,P<0.05)。结论:每日小剂量他达拉非可有效改善PFUD后ED患者的勃起功能,有夜间勃起的患者治疗效果更明显。  相似文献   
10.
背景 术中阴茎勃起是泌尿外科手术中发生率较低的一种并发症,一旦发生可使手术操作困难.虽然至今对于术中阴茎勃起的机制仍然不完全清楚,但是已有的研究表明麻醉方法和麻醉药可影响术中阴茎勃起的发生和发展. 目的 旨在增加临床医生关于麻醉对术中阴茎勃起影响的认识. 内容 系统阐述了术中阴茎勃起的机制,麻醉方法和麻醉药对术中阴茎勃起的可能影响. 趋向 使用恰当的麻醉方法和麻醉药可有效阻止术中阴茎勃起的发生和发展.  相似文献   
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