血管活性肠肽受体拮抗剂VIPhybrid对鸡形觉剥夺性近视眼发展的影响

目的:探讨非选择性血管活性肠肤受体(vasoactive intestinal peptide receptors,VIPR)拮抗剂VIPhybrid对雏鸡眼球后壁组织VIP蛋白质和mRNA表达的调控及对雏鸡形觉剥夺性近视眼(form deprivation myopia,FDM)发生发展的影响.方法:随机选择出生1天龄健康黄色来亨雏鸡共72只,分为6组,每组12只:Ⅰ组单眼遮盖作为空白对照组;Ⅱ组玻璃体腔内注射生理盐水20μL加遮盖作为阴性对照组;Ⅲ组、Ⅳ组、Ⅴ组分别向玻璃体腔内注射低浓度(3×10-12mol/L)、中浓度(3×10-10mol/L)和高浓度(3×10-8mol/L)VIPhybrid,并加遮盖作为实验组;以上各组均取右眼注射并持续遮盖1周;Ⅵ组双眼均未遮盖、未注射药物作为正常对照组.各组均采用视网膜检影验光检测屈光度,眼科A超测定活体眼轴长度,眼球后壁组织行SP法免疫组织化学染色(每组取7只眼)和RT-PCR的方法(每组取5只眼)分别检测VIP蛋白质和mRNA的表达.结果:遮盖1周后,Ⅰ组、Ⅱ组眼轴延长,形成高度近视眼,组间无统计学差异(P＞0.05);Ⅲ组、Ⅳ组、Ⅴ组近视性屈光度数、眼轴长度明显低于Ⅰ,Ⅱ组(P＜0.01),仍高于Ⅵ组(P＜0.01);Ⅲ组、Ⅳ组、Ⅴ组近视性屈先度数、眼轴长度与VIPhybrid浓度呈负相关.VIP在正常视网膜中广泛表达,其中在光感受器外节有强阳性表达;VIP蛋白质和mRNA表达,Ⅲ组、Ⅳ组、Ⅴ组与Ⅰ组、Ⅱ组比较明显下调(P＜0.01),仍高于Ⅵ组(P＜0.01);Ⅲ组、Ⅳ组、Ⅴ组VIP蛋白质和mRNA表达随VIPhybrid浓度的升高而下降.结论:FDM中视网膜VIP蛋白质和mRNA表达明显上调;VIPhybrid可有效减缓鸡FDM的发展,下调鸡FDM中视网膜VIP蛋白质和mRNA的表达,可能为人类近视眼的药物治疗提供一条新思路.

Effect of vasoactive intestinal peptide receptor antagonist VIPhybrid on the development of form deprivation myopia in chicks

Objective To investigate the effect of regulation of VIPhybrid, an unselective antagonist of vasoactive intestinal peptide receptors (VIPR), on the formation and development of form deprivation myopia (FDM) in chick and the expression of protein and mRNA of VIP on the retina and choroids of in chicks. Methods Seventy-two 1-day-old yellow healthy leghorn chicks were assigned into 6 groups (12 in each group). Eyes in Group I were covered on the right as a blank control group. Eyes in GroupII were those eyes having been injected with 20 muL saline into vitreous cavity and then covered as a negative control group. Eyes in GroupIII,IV and V were injected with 20 muL VIPhybrid with low (3*10(-12)mol/L), middle (3*10(-10)mol/L) and high (3*10(-8) mol/L) dosage into vitreous cavity and then covered as experimental groups. The above groups had been continuously covered for 1 week. Eyes in Group VI were uncovered and uninjected as a normal control group. Diopter was detected using retinoscopic refraction. The eyeball axis was determined using ophthalmological ultra-A. The expression of protein and mRNA of VIP on retina-choroids-sclera were investigated by SP immunohistochemistry staining and RT-PCR.Results Form deprivation for 1 week induced high myopia eyes and elongated eyeball axis in GroupI and GroupII, and there was no difference between the 2 groups (P>0.05). The diopter and eyeball axis were significantly reduced in Group III, IV, and V as compared with Group I and II(P<0.01), but the diopter was higher and the eyeball axis was longer than those of Group VI. The diopter and eyeball axis had negative correlation with the concentration gradient of VIPhybrid. The expressions of protein and mRNA of VIP in Group III, IV, and V were down-regulated as compared with those of Group Iand II(P<0.01)and also down-regulated with the increace of concentration of VIPhybrid.Conclusion VIPhybrid can decrease the development of FDM in chicks, which may provide a new pathway for drug therapy of myopia in human beings.