Oku H, Sugiyama T, Moriya S, Hamada J, Azuma I
Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan.
Nippon Ganka Gakkai Zasshi. 1993 Apr;97(4):467-73.
Endothelin, a novel, potent, and long-acting vasoconstrictor peptide, is thought to regulate retinal circulation and its autoregulation. A disturbance in the regulation of endothelin production might contribute to the pathogenesis of retinochoroidal or optic nerve diseases. We examined the effects of endothelin on the retina and the optic nerve using the electroretinogram (ERG) and visual evoked potential (VEP). Six male albino rabbits underwent intravitreal injection of 0.1 ml (10(-5) mol/l) endothelin-1 in the right eye. Six other male albino rabbits, which were injected intravitreally with 0.1 ml of Opeguard-MA in the right eye, were used as controls. Endothelin-1 caused marked constriction of retinal vessels and pallor of the optic nerve head. These findings persisted for 10 days after endothelin-1 injection. The amplitude of the b-wave and the latency of the oscillatory potential in the ERG were not significantly different from those in controls. On the other hand, prolongation of the VEP-N1 latency was observed for 14 days after the injection. These results indicate that endothelin acts on the circulation of the optic nerve head rather than that of the retina, and that effects persist for a relatively long period.
内皮素是一种新型、强效且长效的血管收缩肽，被认为可调节视网膜循环及其自身调节。内皮素产生调节的紊乱可能有助于视网膜脉络膜或视神经疾病的发病机制。我们使用视网膜电图（ERG）和视觉诱发电位（VEP）研究了内皮素对视网膜和视神经的影响。六只雄性白化兔右眼玻璃体内注射0.1 ml（10^(-5) mol/l）内皮素-1。另外六只雄性白化兔右眼玻璃体内注射0.1 ml的Opeguard-MA作为对照。内皮素-1导致视网膜血管明显收缩和视神经乳头苍白。这些发现在内皮素-1注射后持续10天。ERG中b波的振幅和振荡电位的潜伏期与对照组无显著差异。另一方面，注射后14天观察到VEP-N1潜伏期延长。这些结果表明，内皮素作用于视神经乳头的循环而非视网膜的循环，且作用持续较长时间。
