Retrograde axonal transport of BDNF in retinal ganglion cells is blocked by acute IOP elevation in rats.

Published

Journal Article

PURPOSE: To determine whether acute experimental glaucoma in rats obstructs retrograde transport of brain-derived neurotrophic factor (BDNF) to retinal ganglion cells (RGCs). METHODS: Forty rats had unilateral injection of either (125)I-BDNF (20 animals) or a mixture of (125)I-BDNF and 100-fold excess nonradiolabeled BDNF (20 animals). In each group of 20 animals, eyes contralateral to injection had either normal intraocular pressure (IOP; 10 animals) or IOP elevated to 25 mm Hg below the systolic blood pressure of the eye (10 animals). In each group of 20 rats, ipsilateral eyes had IOP set at systolic blood pressure (4 eyes), had optic nerve transection (10 eyes), or had normal IOP (6 eyes). Six hours after injection, animals were killed and tissues were fixed, embedded, and sectioned for autoradiography. Grain counts were performed over retina and optic nerve using automated image analysis. RESULTS: IOP elevation to 25 mm Hg below systolic blood pressure (perfusion pressure [PP] 25) decreased median retinal nerve fiber layer (NFL) grains by 38% compared with controls (P: < 0.001). Competition by cold BDNF reduced NFL grains by 28% (P: = 0.013). Considering only the radioactivity representing specific retrograde transport of BDNF, IOP elevation to PP25 reduced transport by 74%, whereas elevation to PP0 (equaling systolic blood pressure) reduced specific transport by 83%. CONCLUSIONS: BDNF is transported retrogradely from the superior colliculus in adult rats, and this transport is substantially inhibited by acute IOP elevation. Deprivation of BDNF among RGCs may contribute to neuron loss in glaucoma.

Full Text

Duke Authors

Cited Authors

  • Quigley, HA; McKinnon, SJ; Zack, DJ; Pease, ME; Kerrigan-Baumrind, LA; Kerrigan, DF; Mitchell, RS

Published Date

  • October 2000

Published In

Volume / Issue

  • 41 / 11

Start / End Page

  • 3460 - 3466

PubMed ID

  • 11006239

Pubmed Central ID

  • 11006239

International Standard Serial Number (ISSN)

  • 0146-0404

Language

  • eng

Conference Location

  • United States