Protective effects of vasoactive intestinal peptide (VIP) in ischemic retinal degeneration

J Mol Neurosci. 2012 Nov;48(3):501-7. doi: 10.1007/s12031-012-9774-9. Epub 2012 Apr 29.

Abstract

Vasoactive intestinal peptide (VIP) is a pleiotropic neuropeptide, acting as a neuromodulator and neuroprotective peptide in the CNS after injuries. We have previously described that pituitary adenylate cyclase-activating polypeptide (PACAP), another member of the same peptide family, is retinoprotective in ischemic lesions. The aim of this study was to investigate the protective potential of VIP in bilateral common carotid artery occlusion (BCCAO)-induced ischemic retinal lesion. Two-month-old rats were subjected to BCCAO and treated with intravitreal VIP injection. Their retinas were processed for histology after 2 weeks of survival. We measured the number of the cells/100 μm of the ganglion cell layer and the thickness of each layer such as the outer nuclear, outer plexiform, inner nuclear, and inner plexiform layers as well as that of the whole retina. We found that treatment with 1,000 pmol VIP, but not 100 pmol VIP, had significant protective effects in BCCAO-injured retina, as shown by the morphometric analysis. Comparing the neuroprotective effects of VIP and PACAP in BCCAO-operated retinas, PACAP was more effective, already protective at 100-pmol doses. Similar to other studies, we found that VIP must be given at least in 10 times more concentration than PACAP to achieve a similar degree of neuroprotection in the retina.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Carotid Artery, Common*
  • Carotid Stenosis / complications*
  • Dose-Response Relationship, Drug
  • Drug Evaluation, Preclinical
  • Intravitreal Injections
  • Ischemia / drug therapy*
  • Ischemia / etiology
  • Ischemia / pathology
  • Male
  • Models, Neurological
  • Neuroprotective Agents / pharmacology
  • Neuroprotective Agents / therapeutic use*
  • Pituitary Adenylate Cyclase-Activating Polypeptide / administration & dosage
  • Pituitary Adenylate Cyclase-Activating Polypeptide / pharmacology
  • Pituitary Adenylate Cyclase-Activating Polypeptide / therapeutic use
  • Rats
  • Rats, Wistar
  • Retinal Degeneration / etiology
  • Retinal Degeneration / pathology
  • Retinal Degeneration / prevention & control*
  • Retinal Neurons / drug effects
  • Retinal Neurons / ultrastructure
  • Retinal Vessels
  • Retinitis / drug therapy
  • Retinitis / etiology
  • Retinitis / pathology
  • Time Factors
  • Vasoactive Intestinal Peptide / administration & dosage
  • Vasoactive Intestinal Peptide / pharmacology
  • Vasoactive Intestinal Peptide / therapeutic use*

Substances

  • Neuroprotective Agents
  • Pituitary Adenylate Cyclase-Activating Polypeptide
  • Vasoactive Intestinal Peptide