阴茎包埋对海绵体内勃起通路的影响

目的 观察阴茎包埋对海绵体内勃起通路的影响.方法 通过建立大鼠隐匿阴茎模型获得实验标本,分2、4、6个月组进行观测.各阶段中包括包埋组、假手术组和正常组.采用紫外分光光度计检测海绵体内一氧化氮合酶(NOS)的活性,免疫组织化学法显示雄激素受体(AR)在海绵体内的表达水平.结果 3个时间段内包埋组NOS活性分别为1.79、1.67、1.24 U/mg·prot,与正常组和对照组比较,酶活性降低随包埋时间延长逐渐显著(2个月组P>0.05,4个月组P<0.05,6个月组P<0.01),但包埋对各阶段大鼠阴茎海绵体内AR表达水平无影响.结论 阴茎包埋可直接影响勃起通路中最重要的神经递质一氧化氮合成的关键酶-NOS的活性来影响勃起通路,且这种影响与阴茎包埋时间正相关.     

阴茎包埋对海绵体形态结构的影响

目的:探讨阴茎包埋对大鼠阴茎海绵体形态结构的影响。方法:通过建立隐匿阴茎大鼠模型获得实验标本,分2月组、4月组进行观测,每组25只大鼠。各阶段又分包埋组(15只)、正常组(10只),光镜和电镜下观察海绵体形态结构的改变。结果:阴茎包埋2月组海绵体形态结构无明显变化,4月组病理改变较为明显,光镜下见大鼠阴茎海绵体平滑肌细胞,内皮细胞分布杂乱,细胞间大量间质组织增生,海绵窦狭窄;电镜下见阴茎海绵体平滑肌细胞及内皮细胞萎缩、线粒体退变、内质网扩张,致密体及收缩纤维减少,脂滴增加,空泡形成。包埋组与正常组阴茎海绵体在外观和重量上无明显差异(P>0.05)。结论:阴茎包埋对海绵体外观和重量无明显影响,但随着包埋时间的延长,海绵体组织发生超微结构上的病理改变。     

慢性肾功能衰竭性勃起功能障碍大鼠阴茎海绵体有效成分的测定

目的:探讨慢性肾功能衰竭(CRF)性勃起功能障碍(ED)的发病机制。方法:应用SD雄性大鼠分两期行5/6肾脏切除术,建立CRF动物模型。将假手术组(NCRF组,n=30)、CRF模型大鼠(CRF组,n=45)分别随机均分为Ⅰ(2周)、Ⅱ(4周)、Ⅲ(6周)3组,并分别于2、4、6周注射阿朴吗啡(APO,80μg/kg)后观察大鼠阴茎勃起情况,筛选CRF性ED模型大鼠;测定阴茎海绵体组织一氧化氮合酶(NOS)的活性,及其组织的M asson染色图像分析。结果:CRF性ED大鼠阴茎海绵体组织NOS活性及平滑肌面积显著降低(P<0.01或P<0.05),胶原纤维略有增加,且上述变化与CRF病程密切相关。海绵窦血管腔无明显变化。结论:CRF严重影响阴茎勃起功能,阴茎海绵体组织NOS活性降低及阴茎海绵体平滑肌面积的减少可能是其重要的发病机制。     

FK506对大鼠阴茎海绵体神经再生影响的研究

目的:探讨FK506对大鼠阴茎海绵体神经损伤后再生的影响,并讨论其作用的可能机制。　方法:54只 SD雄性大鼠随机分成3组,即假手术对照组(简称对照组,n=24)、单侧阴茎海绵体神经切断组(简称单切组,n= 24)、单侧阴茎海绵体神经切断+FK506组(简称FK506组,n=6)。术后1、3个月电刺激阴茎海绵体神经并连续监 测阴茎海绵体内压变化及阴茎勃起情况,同时取阴茎海绵体组织采用NADPH d法观察一氧化氮合酶(nNOS)阳性 神经纤维的再生情况。　结果:术后1个月单切组nNOS阳性神经纤维数量明显减少,与对照组相比差异有极显 著性(P<0.01),术后3个月在电刺激未切断侧阴茎海绵体神经时,FK506组比单切组产生更大的最大海绵体内压 (P<0.01),且单切组阴茎海绵体组织中nNOS阳性神经纤维比术后1个月无明显增加(P>0.05),而FK506组 nNOS阳性神经纤维显著增加(P<0.01)。　结论:FK506皮下注射能促进大鼠损伤的阴茎海绵体神经再生,促进 勃起功能恢复。     

甲状腺素对大鼠阴茎海绵体内NOS及CO含量影响的研究

目的:建立甲状腺功能亢进及甲状腺功能减退Wistar大鼠动物模型,检测其阴茎海绵体内NOS及内源性一氧化碳(CO)的含量,探讨甲状腺素对大鼠勃起功能的影响及内源性CO在阴茎海绵体勃起过程中的作用,进一步讨论甲状腺素对人类勃起功能的影响。方法:将50只3月龄雄性Wistar大鼠随机均分为甲亢组、甲亢治疗组、甲减组、甲减治疗组及正常对照组。用紫外分光光度计分别测定阴茎海绵体内NOS及CO的含量。结果:无论甲状腺素增多及减少都会使大鼠阴茎海绵体NOS含量降低(P<0.01),并且甲减组阴茎海绵体内NOS活性低于甲亢组(P<0.01)。无论甲状腺素增多还是减少都会使大鼠阴茎海绵体内CO含量降低(P<0.01),并且甲亢组阴茎海绵体内CO活性低于甲减组(P<0.01)。在对甲减组及甲亢组进行治疗后其CO及NOS的含量得到提高,与正常对照组无显著差异(P>0.05)。结论:甲状腺功能紊乱情况下阴茎海绵体中NOS和CO的浓度均减低;甲状腺功能紊乱被及时纠正后阴茎海绵体中CO及NOS的含量可恢复到正常水平。在相同条件下甲状腺功能低下对性功能的损害强于甲状腺功能亢进对勃起功能的损害。     

阴茎包埋对海绵体结构和发育的影响

目的探讨阴茎包埋对海绵体结构和发育的影响。方法通过建立隐匿阴茎动物模型获得实验标本，分2个月组、4个月组和6个月组进行观测。检测海绵体质量和大鼠体重，观察发育情况；Masson染色分析海绵体内平滑肌和纤维结缔组织的含量来了解海绵体结构的变化。结果各阶段包埋组动物阴茎海绵体质量、体重及两者的比值与正常组和假手术组两两比较差异均无统计学意义（P〉0．05）；各阶段中包埋组的海绵体平滑肌面积下降（2个月组P〉0．05，4个月和6个月组P〈0．05），纤维结缔组织面积增加（2个月和4个月组P〉0．05，6个月组P〈0．05）血管窦的面积减少（2个月和4个月组P〉0．05，6个月组P〈0．05），且组织的正常形态发生改变。结论阴茎包埋可影响海绵体内平滑肌和纤维结缔组织的含量及组织排列的正常形态，且与包埋时间正相关，但对海绵体的大体观无明显影响。     

香烟烟雾对雄性大鼠性功能影响的实验研究

目的:研究香烟烟雾对雄性大鼠性功能的影响。方法:30只SD雄性大鼠随机均分为两组,吸烟组制备大鼠吸烟模型,使用市售红金龙过滤咀香烟(每支焦油含量13mg),吸烟组每日使其被动吸烟4次,每次两支,每次30min持续60d;对照组正常饲养。实验结束前1周两组动物笼中分别放入5只雌性大鼠,采用24h监控录像监测观察骑跨动作1周,60d后处死取标本。测定大鼠血中睾酮水平及阴茎海绵体组织一氧化氮合酶(NOS)的活性,行阴茎海绵体组织的Masson染色图像分析。结果:吸烟组大鼠骑跨动作次数减少,血中睾酮水平明显降低(P<0.05),阴茎海绵体组织NOS活性及平滑肌面积显著降低(P<0.05),胶原纤维明显增加,海绵窦血管腔有明显变化。结论:吸烟组大鼠阴茎勃起功能受到明显影响,睾酮水平降低及阴茎海绵体组织NOS活性降低、阴茎海绵体平滑肌面积的减少可能是其重要的发病机制。     

2型糖尿病大鼠血浆同型半胱氨酸与阴茎海绵体内NOS和内源性CO的相关性研究

目的:研究2型糖尿病性大鼠血浆同型半胱氨酸(Hcy)与阴茎海绵体内NOS和内源性CO的相关性。方法:选取3月龄雄性Wistar大鼠50只,随机选取10只为对照组(A组);高糖高脂饲料饲养4周后从其他40只大鼠中筛选出30只构建成功的糖尿病(DM)大鼠模型,随机分成3组:DM大鼠组(B组);胰岛素治疗组(C组)和叶酸+维生素B12治疗组(D组)。8周及12周后注射阿朴吗啡观察各组大鼠阴茎勃起情况。12周后测各组大鼠血浆总Hcy含量及阴茎海绵体内NOS活性和CO含量。结果:与A组比较,B组大鼠血浆Hcy浓度明显升高,阴茎勃起功能明显降低,阴茎海绵体NOS活性和CO含量均下降,差异有显著性(P<0.01)。2型DM大鼠中高Hcy血症发生率为55%。与B组比较,C组和D组中大鼠血浆Hcy浓度显著下降,阴茎勃起功能、阴茎海绵体NOS活性均升高(P<0.01),Hcy与NOS(rA=-0.89,rB=-0.76,rC=-0.91,rD=-0.91)及CO含量(rA=-0.82,rB=-0.77,rC=-0.93,rD=-0.81)均呈负相关。结论:2型DM大鼠血浆中的高Hcy可能是引起阴茎海绵体NOS活性下降、CO含量下降,进而导致DM ED发病的分子机制之一。胰岛素、叶酸和维生素B12可以改善DM大鼠的勃起功能,提高阴茎海绵体NOS活性和CO含量。     

高血压大鼠海绵体平滑肌细胞间连接的变化

目的:比较自发性高血压大鼠(SHR)和正常血压大鼠阴茎海绵体平滑肌细胞间连接改变及与阴茎勃起功能的关系。方法:注射阿朴吗啡(APO)观察14周龄SHR(SHR组,n=5)、W istar-Kyoto大鼠(WKY组,n=5)阴茎勃起情况,用透射电镜观察其阴茎海绵体平滑肌细胞间连接超微结构,RT-PCR测定海绵体平滑肌细胞Connexin 43的mRNA表达,免疫组化观察Connexin 43蛋白表达。结果:SHR组大鼠阴茎勃起次数明显低于WKY组(P<0.05),电镜发现SHR组大鼠阴茎海绵体平滑肌细胞间大量胶原纤维增生,Connexin 43蛋白及其mRNA表达较WKY组显著降低(P<0.05)。结论:高血压影响阴茎勃起功能,阴茎海绵体平滑肌细胞间连接的病理改变可能是高血压性勃起功能障碍的发病机制之一。     

去势对大鼠阴茎海绵体功能和结构的影响

目的 :探讨雄激素对阴茎海绵体功能和结构的影响。　方法 :30只成年雄性大白鼠随机分为 3组 :阉割组、替代组及假手术对照组。于 1周后取阴茎海绵体 ,用紫外分光光度计测定其一氧化氮合酶 (NOS)活性 ,同时用ISEL法检测其细胞凋亡情况。　结果 :阉割组海绵体NOS活性下降 70 %并出现细胞凋亡 (P <0 .0 1) ,睾酮替代能阻止NOS活性降低及凋亡的发生 (P >0 .0 5 )。　结论 :雄激素可通过调节NOS活性及细胞的增殖与凋亡而维持阴茎海绵体的结构与功能。     

Nitric oxide synthase gene transfer for erectile dysfunction in a rat model

OBJECTIVE: To determine whether over-expression of nitric oxide synthase (NOS) in the corpus cavernosum of the penis improves erectile function, as NO is an important transmitter for genitourinary tract function, mediating smooth muscle relaxation and being essential for penile erection. MATERIALS AND METHODS: The inducible form of the enzyme NOS (iNOS) was introduced into the corpus cavernosum of adult Sprague-Dawley rats (250-300 g) by injecting a solution of plasmid, adenovirus or adenovirus-transduced myoblast cells (adeno-myoblasts). Plasmid, adenovirus and adeno-myoblasts encoding the expression of the beta-galactosidase reporter gene were also injected into rats. RESULTS: Throughout the corpora cavernosum there was expression of beta-galactosidase after injecting each of the three solutions. Maximum staining was greatest for adeno-myoblast, then adenovirus and then plasmid. The mean (sd) basal intracavernosal pressure (ICP) of iNOS-treated animals (adenovirus and adeno-myoblast) increased to 55 (23) cmH2O, compared with naive animals with a basal ICP of 5 (6) cmH2O (P = 0.001). Stimulating the cavernosal nerve (15 Hz, 1.5 ms, 10-40 V, 1 min) resulted in a doubling of the ICP (adenovirus and adeno-myoblast) from the basal level of the iNOS-treated animals. Direct in situ measurement of NO showed the release of 1-1.3 micro mol/L in the adeno-myoblast penis. CONCLUSION: Myoblast-mediated gene therapy was more successful for delivering iNOS into the corpus cavernosum than direct adenovirus injection or plasmid transfection. Surprisingly, implanting muscle cells into the penis is not only feasible but also beneficial. Gene therapy for NOS may open new avenues of treatment for erectile dysfunction. Control of NOS expression would be necessary to prevent priapism.     

Electrical activity of the corpus cavernosum in denervated rats

BACKGROUND: We evaluated the electrical activity of the corpus cavernosum after intracavernous papaverine injection in rats that had been denervated experimentally. METHODS: Twenty-four male adult Sprague Dawley rats were divided into three groups: (i) controls (n=8) (ii) unilateral cavernous nerve resection on the right side (n=8); and (iii) bilateral cavernous nerve resection (n=8). Through a suprapubic incision, the urinary bladder was retracted laterally to locate the major pelvic plexus on the lateral surface of the prostate. The major branch of the cavernous nerve, running caudally from the pelvic plexus, was isolated and excised using an operating microscope. Three weeks later, recording of the electrical activity of the corpus cavernosum (EACC) was performed by using a Neuropack-2 EMG unit (Nihon Kohden, Tokyo, Japan) and coencentric needle electrode. Changes in amplitude were evaluated before and after intracavernosal papaverine injection. The results in the flaccid state and after papaverine injection were compared by using the Mann Whitney U-test in all three groups and paired t-test between groups. RESULTS: In the flaccid penis, the mean (+/- SD) amplitude of electrical activity of the corpus cavernosum was 17.42+/-2.05, 12.42+/-1.88, 9.71+/-1.59 and 5.85+/-0.96 microV in control rats, in unilaterally denervated rats (in which the cavernous nerve was intact on the left side), in unilaterally denervated rats in which the cavernous nerve was resected on the right side and in bilaterally denervated rats, respectively. In the flaccid state, EACC is lower in the bilaterally denervated group than in the control and unilaterally nerve-resected groups (P < or = 0.05). The recording of electrical activity of the corpus cavernosum was continued for 20 min after papaverine injection. In the control group and in both groups of unilaterally denervated rats, we observed a significant decrease in the electrical activity of the corpus cavernosum in the first 5 min after papaverine injection (P < or = 0.05). However, no difference was observed in bilaterally denervated rats after injection (P > or = 0.05). CONCLUSIONS: We conclude that electrical activity of the corpus cavernosum continues after unilateral nerve injury in rats. Cross-innervation may play a role in penile innervation and corpus cavernosum electromyography shows electrical activity in denervated rats.     

The effects of melatonin on ischemia-reperfusion induced changes in rat corpus cavernosum

PURPOSES: We determined the change in contractile activity and oxidant damage after ischemia-reperfusion of rat corpus cavernosum and investigated the effects of melatonin (Sigma Chemical Co., St. Louis, Missouri) on these parameters. MATERIALS AND METHODS: The abdominal aorta of male Wistar albino rats was occluded to induce ischemia-reperfusion. Melatonin (10 mg./kg.) or vehicle (1% alcohol in saline per kg.) was administered subcutaneously before ischemia-reperfusion. In the sham operated control group the abdominal aorta was left intact and the rats were treated with melatonin or vehicle. After decapitation corporeal tissues were placed in organ baths or stored for biochemical measurements. RESULTS: In sham operated rats phenylephrine added cumulatively caused a concentration dependent contraction in corpus cavernosum strips precontracted with KCl and acetylcholine added cumulatively to strips precontracted with phenylephrine caused a dose dependent relaxation response. In the ischemia-reperfusion group contraction and relaxation responses decreased significantly compared within controls. Melatonin treatment in the ischemia-reperfusion group reversed these responses. Myeloperoxidase activity and the lipid peroxidation level of the corporeal tissues in the ischemia-reperfusion group were significantly higher than in the sham operated control group. Melatonin treatment in the ischemia-reperfusion group decreased myeloperoxidase activity and the lipid peroxidation level compared with ischemia-reperfusion alone, whereas melatonin treatment alone had no significant effect on these parameters. CONCLUSIONS: In this study the corporeal tissues of rats exposed to ischemia-reperfusion had lower responses to contractile and relaxant agents than those of sham operated rats. Treatment with melatonin before ischemia-reperfusion almost completely reversed smooth muscle responses and prevented the increased myeloperoxidase activity and lipid peroxidation of corporeal tissues.     

两种隐匿阴茎大鼠模型的建立及比较

目的:建立稳定的大鼠隐匿阴茎模型,为探索阴茎包埋对海绵体结构和功能的影响提供实验动物模型。方法:90只2周龄雄性SD大鼠随机均分为A、B、C3组,A组采用阴茎根部内荷包缝合法,B组采用包皮折叠缝合法包埋阴茎,C组为假手术组。在180d内观察两种方法的包埋效果。结果:A组术后4只死于急性尿潴留,5只因尿道口周围软组织感染、皮肤破溃导致包埋失败,3只因包埋过松阴茎伸出;B组术后1只死于麻醉,2只死于急性尿潴留;因阴茎发育和勃起,A组有7只、B组有10只阴茎伸出;C组1只死于麻醉。A组和B组中其余大鼠均有较好的包埋效果,A组包埋成功率为36.7%,B组为56.7%,而且可以在实验中任何时候解除包埋。结论:包皮折叠缝合法和阴茎根部内荷包缝合法均能建立稳定的、且与人类隐匿阴茎自然病程较为一致的2周龄大鼠隐匿阴茎动物模型。     

大鼠盆神经节NOS和VIP阳性神经元对阴茎海绵体的支配

目的：研究大鼠盆神经节(MPG)中一氧化氮合酶(NOS)、血管活性肠肽(VIP)阳性神经元对阴茎海绵体的支配。方法：应用辣根过氧化物酶(HRP)逆行示踪技术结合免疫组织化学和酶组织化学双标技术,观察大鼠MPD中还原型辅酶Ⅱ(NADPFI,NOS标志物)阳性和VIP阳性神经元对阴茎海绵体的支配。结果：HRP阳性标记神经元主要分布于MPG内靠近阴茎神经的区域。HRP阳性标记神经元中72％(210／292)为VIP免疫阳性,83％(268／323)为NADPH组化反应阳性。结论：大鼠盆神经节中NOS、VIP阳性神经元对阴茎海绵体有直接支配,NO和VIP作为神经递质或调质参与了阴茎勃起。