Please use this identifier to cite or link to this item:
|Title:||Expression of trkA, trkB, and trkC in injured and regenerating retinal ganglion cells of adult rats|
|Authors:||So, KF;Yip, HK;Cui, Q;Tang, LS;Hu, B|
|Publisher:||Association for Research in Vision and Ophthalmology. The Journal's web site is located at http://www.iovs.org|
|Description:||PURPOSE. To investigate changes in percentage of tyrosine kinase (trk)A-, trkB-, and trkC-immunopositive ( +) retinal ganglion cells (RGCs) at various times after optic nerve (ON) axotomy; the proportion of RGCs regenerating axons into peripheral nerve (PN) grafts that are trkA +, trkB +, and trkC +; whether intravitreal PN-ON implants affect trk immunoreactivity; and the levels of trk mRNAs in ON-injured retinas. METHODS. The ON was transected intraorbitally. Proportions of trkA +, trkB +, and trkC + RGCs and levels of trk mRNAs were studied by using immunocytochemistry and Northern blot methods, respectively, in injured and RGC-regenerating retinas. RESULTS. In normal retinas, only small numbers of trkB + and trkC +, but not trkA +, RGCs were seen. The optic fiber layer was intensively immunolabeled with trkB. After ON injury, the proportions of trkA +, trkB +, and trkC + RGCs rapidly increased and reached their peaks by 3 to 5 days. During the next 3 weeks, the proportion of trkA + or trkB + RGCs gradually decreased, but the proportion of trkC + RGCs remained high. Intravitreal implants of PN+ON segments transiently but significantly suppressed injury-induced increases in all these trk + RGC proportions for approximately 5 days. In contrast, 3 days after ON injury, quantitative retinal expression of trkA mRNA, and to a lesser extent trkC mRNA, was downregulated, whereas trkB mRNA expression remained unaffected. Higher proportions of trkA + and trkB + RGCs and higher levels of all trk mRNAs were seen in regenerating RGCs and retinas, respectively. CONCLUSIONS. This study provides a kinetic analysis of expression of trk in RGCs and retinas after ON injury and during regeneration.|
|Standard no:||Investigative Ophthalmology And Visual Science, 2002, v. 43 n. 6, p. 1954-1964|
|Appears in Collections:||Department of Anatomy|
Files in This Item:
Click on the URI links for accessing contents.
Items in HannanDL are protected by copyright, with all rights reserved, unless otherwise indicated.