晚期糖基化终产物对大鼠阴茎海绵体组织中一氧化氮含量及其合成酶活性的影响

Effect of Advanced Glycation End Products on the Content of Nitric Oxide and the Activity of Nitric Oxide Synthase in Rat Cavernosum

通过观察大鼠阴茎海绵体组织中晚期糖基化终产物(AGEs)含量的变化对一氧化氮(NO)含量及其合成酶(NOS)活性的影响,探讨AGEs在糖尿病性勃起功能障碍(DMED)发生发展中的作用.成年雄性SD大鼠60只,随机取40只用于制作糖尿病模型,造模成功的大鼠分为两组:糖尿病(DM)组和糖尿病+氨基胍给药(DM+AG)组;另20只大鼠亦分为两组:正常对照(CONTROL)组和正常对照+氨基胍给药(CONTROL+AG)组;氨基胍(AG)给药组大鼠造模后即在其饮水中按1g/L剂量加入AG.饲养8周后取各组大鼠阴茎海绵体组织,匀浆后检测AGE-肽(AGE-P)含量、NO含量及各型NOS酶活性.DM组阴茎海绵体组织中AGE-P含量、NO含量及诱导型NOS(iNOS)活性明显高于CONTROL组(P<0.05),而结构型NOS(cNOS)活性则明显低于后者(P<0.05),而AG则明显减少了DM大鼠阴茎海绵体组织中AGE-P、NO的生成和减弱了iNOS活性,增强了cNOS活性;CONTROL组与CONTROL+AG组间比较在各项指标上则无明显差异(P>0.05).糖尿病状态下AGEs可以引起大鼠阴茎海绵体组织中cNOS活性减弱,iNOS活性增强,过量的NO生成,可能引起阴茎组织细胞的凋亡,导致阴茎勃起功能的损伤.

In order to illuminate the role of advanced glycation end products （AGEs） in the pathogenesis of diabetic mellitus erectile dysfunction （DMED）, we investigated the effect of AGEs on the content of nitric oxide （NO）and the activity of nitric oxide synthase （NOS）in rat cavernosum. Forty rats were taken out from 60 male Sprague- Dawley rats at random for diabetes mellitus （DM） models. One group of DM rats was given free access to water. The second group was given aminoguanidine （AG） with their water （1 g/L） from the initiation of DM. Two groups of rats that were not DM acted as age-matched controls. Therefore all rats were divided into four groups. DM,DM＋AG, CONTROL, CONTROL＋AG . After eight weeks each rat cavernosum tissue was harvested and homogenated to detect the content of AGE-peptide （AGE-P）, NO and the activity of NOS. Compared with CONTROL group, the content of AGE-P, NO and the activity of inducible nitric oxide synthase（iNOS）in rat cavernosum tissue were significantly high in DM group （P〈0. 05）, but the activity of constitutive nitric oxide synthase （cNOS）were significantly low in DM group （P〈0.05） ; The administration of AG to DM rats reversed the above results; There was no difference between CONTROL and CONTROL＋AG groups in all datas （P〉0. 05）. In the DM condition , AGEs can attenuate the activity of cNOS in rat cavernosum tissue , while raise the activity of iNOS and result in the overproduction of NO. All these changes may result in the impairment of penile erectile function.