Urocortin 2 protects against retinal degeneration following bilateral common carotid artery occlusion in the rat

Neurosci Lett. 2009 May 8;455(1):42-5. doi: 10.1016/j.neulet.2009.03.013. Epub 2009 Mar 11.

Abstract

Urocortin 2 (Ucn 2) is corticotropin-releasing factor (CRF) paralog that preferentially activates CRF(2) receptors. Ucns exert CRF(2)-mediated cytoprotective effects against ischemia-reperfusion injury in cardiomyocytes. However, little is known regarding potential retinoprotective effects of Ucns despite the known presence of CRF family peptides and their receptors (predominantly CRF(2 alpha)) in retina. Therefore, the present study investigated the effects of post-ischemic intravitreal Ucn 2 (2 nmol) administration on ischemia-induced retinal degeneration. Two-month-old rats were subjected to permanent bilateral common carotid artery occlusion, and their retinas were processed histologically after two weeks survival to determine the density of viable cells in the ganglion cell layer and the thickness of all retinal layers. In vehicle-treated subjects, carotid occlusion reduced retina thickness by approximately 60% as compared to sham-operated animals. In contrast, intraocular Ucn 2 treatment led to a marked amelioration of the retinal layers, and the thickness of all layers was significantly increased by 40% compared to ischemic vehicle-treated subjects. Ucn 2 treatment also increased the number of cells by 55% in the ganglion cell layer as compared to those from carotid-occluded retinas of vehicle-treated subjects. These findings suggest that intraocular Ucn 2 treatment may protect against ischemia-induced retinal degeneration, results with potential therapeutic implications for ophthalmic diseases.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arterial Occlusive Diseases / complications*
  • Carotid Artery Diseases / complications*
  • Carotid Artery, Common
  • Cell Count
  • Corticotropin-Releasing Hormone / administration & dosage
  • Corticotropin-Releasing Hormone / therapeutic use*
  • Injections
  • Ischemia / complications
  • Mice
  • Rats
  • Rats, Wistar
  • Receptors, Corticotropin-Releasing Hormone / agonists
  • Retina / pathology
  • Retinal Degeneration / etiology
  • Retinal Degeneration / pathology
  • Retinal Degeneration / prevention & control*
  • Urocortins / administration & dosage
  • Urocortins / therapeutic use*
  • Vitreous Body

Substances

  • CRF receptor type 2
  • Receptors, Corticotropin-Releasing Hormone
  • Urocortins
  • urocortin 2, mouse
  • Corticotropin-Releasing Hormone