使用MRI检测药物经静脉注射后在兔眼内的分布

Assessment of the distribution of Gd-DTPA after ear vein injection with magnetic resonance imaging in vivo

目的:使用磁共振(magnetic resonance imaging,MRI)及造影剂——水溶性药物钆喷酸葡胺(Gadolinium-diethylene triamine pentaacetic acids,Gd-DTPA)检测兔静脉注射后药物的渗透性和眼内分布。方法:MRI的造影剂Gd-DTPA作为示踪剂,在活体兔耳缘静脉注射0.5mol/L,0.2mL/kg造影剂,MRI连续扫描2h,观察药物的渗透性、眼内分布,通过感兴趣区时间相关的信号增强率分析影像。结果:睫状体信号快速增强,此后随时间逐渐下降,前房信号逐渐增强,后房及玻璃体信号无增强。结论:药物不进入后房,经过睫状体由虹膜根部直接进入前房,MRI可于活体内定量分析静脉注射药物后的渗透效率,作为非侵袭、动态、实时的检查方法是对传统药代动力学研究方法的有力补充。

AIM：To assess the permeability and distribution of Gadolinium-diethylene triamine pentaacetic acids（Gd-DTPA） after ear vein injection with nuclear magnetic resonance imaging（MRI） .·METHODS：Gd-DTPA which was taken as tracer was injected through ear vein 0.5mol/L,0.2mL/kg. The permeability and distribution of Gd-DTPA were determined by 2 hours MRI successive scanning. The images were analyzed through time-dependent signal enhancement rate of the interest areas.·RESULTS：The ciliary body showed an immediate sharp increase,followed by a gradual decrease in signal enhancement with time. Although a gradual increase in signal enhancement was found in the anterior chamber,no significant change occurred in the posterior chamber.·CONCLUSION：Drugs bypass the posterior chamber,entering the anterior chamber directly via the iris root. The permeability and distribution of probe in vivo can be quantitatively analyzed by MRI. MRI is a noninvasive,dynamic and real time complementary technique to traditional pharmacokinetic methods.