Agarwal Neeraj, Agarwal Rajnee, Kumar Domalapalli Maneesh, Ondricek Amber, Clark Abbot F, Wordinger Robert J, Pang Iok-Hou
Department of Cell Biology and Genetics, UNT Health Science Center, Fort Worth, TX 76107, USA.
Mol Vis. 2007 Jul 25;13:1311-8.
To determine the expression profile of neurotrophins and their receptors in cultured primary rat retinal ganglion cells (RGCs) and the transformed RGC-5 cells.
Confocal microscopic immunocytochemistry with double fluorescent labeling with thy-1 as a marker for RGCs was used to demonstrate expression of neurotrophins and their receptors. An enzyme-linked immunosorbent assay (ELISA) was used to detect secretion of neurotrophins by RGC-5 cells.
Primary RGCs and RGC-5 cells expressed brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT3), neurotrophin-4 (NT4), and receptors TrkA, p75, with low levels of TrkB. However, minimal if any, expression of TrkC was observed in these cells. RGC-5 cells also secreted NT3 (1311+/-21 pg/ml), BDNF (92+/-9 pg/ml), NGF (86+/-7 pg/ml), and NT4 (21+/-1 pg/ml) into the cultured media.
These results demonstrated that neurotrophins and TrkA, p75 with low levels of TrkB receptors are expressed by RGCs. Specific neurotrophins acting through TrkA, TrkB, and p75 receptors within the RGCs may be involved in the survival and apoptosis of the RGCs in various retinopathies, such as glaucoma.
确定神经营养因子及其受体在原代培养的大鼠视网膜神经节细胞（RGCs）和转化的RGC-5细胞中的表达谱。
采用共聚焦显微镜免疫细胞化学技术，以thy-1作为RGCs的标志物进行双重荧光标记，以证明神经营养因子及其受体的表达。采用酶联免疫吸附测定（ELISA）检测RGC-5细胞分泌神经营养因子的情况。
原代RGCs和RGC-5细胞表达脑源性神经营养因子（BDNF）、神经生长因子（NGF）、神经营养因子-3（NT3）、神经营养因子-4（NT4）以及受体TrkA、p75，TrkB表达水平较低。然而，在这些细胞中观察到TrkC的表达极少或几乎没有。RGC-5细胞还向培养基中分泌NT3（1311±21 pg/ml）、BDNF（92±9 pg/ml）、NGF（86±7 pg/ml）和NT4（21±1 pg/ml）。
这些结果表明RGCs表达神经营养因子以及TrkA、p75和低水平的TrkB受体。通过RGCs内的TrkA、TrkB和p75受体起作用的特定神经营养因子可能参与各种视网膜病变（如青光眼）中RGCs的存活和凋亡。
