Department of Anatomy and Neurobiology, School of Basic Medical Science, Central South University, Changsha 410013, Hunan Province, PR China.
Acta Histochem Cytochem. 2013 Feb 28;46(1):11-8. doi: 10.1267/ahc.12029. Epub 2013 Feb 13.
Acute high intraocular pressure (HIOP) can induce plastic changes of retinal synapses during which the expression of the presynaptic marker synaptophysin (SYN) has a distinct spatiotemporal pattern from the inner plexiform layer to the outer plexiform layer. We identified the types of neurotransmitters in the retina that participated in this process and determined the response of these neurotransmitters to HIOP induction. The model of acute HIOP was established by injecting normal saline into the anterior chamber of the rat eye. We found that the number of glutamate-positive cells increased successively from the inner part to the outer part of the retina (from the ganglion cell layer to the inner nuclear layer to the outer nuclear layer) after HIOP, which was similar to the spatiotemporal pattern of SYN expression (internally to externally) following HIOP. However, the distribution and intensity of GABA immunoreactivity in the retina did not change significantly at different survival time post injury and had no direct correlation with SYN expression. Our results suggested that the excitatory neurotransmitter glutamate might participate in the plastic process of retinal synapses following acute HIOP, but no evidence was found for the role of the inhibitory neurotransmitter GABA.
急性高眼压（HIOP）可诱导视网膜突触发生塑性变化，在此过程中，突触小泡蛋白（SYN）的表达从前层到外丛状层呈现出明显的时空模式。我们鉴定了参与此过程的视网膜神经递质的类型，并确定了这些神经递质对 HIOP 诱导的反应。通过向大鼠眼前房内注射生理盐水建立急性 HIOP 模型。我们发现，HIOP 后，谷氨酸阳性细胞的数量从视网膜的内部分别依次增加到外部分（从神经节细胞层到内核层到外核层），这与 HIOP 后 SYN 表达的时空模式（从内到外）相似。然而，损伤后不同存活时间内视网膜中 GABA 免疫反应的分布和强度没有明显变化，与 SYN 表达也没有直接关系。我们的结果表明，兴奋性神经递质谷氨酸可能参与急性 HIOP 后视网膜突触的塑性过程，但没有证据表明抑制性神经递质 GABA 起作用。
