December 2002
Volume 43, Issue 13
Free
ARVO Annual Meeting Abstract  |   December 2002
Expression of -Interferon mRNA by Astrocytes
Author Affiliations & Notes
  • BJ Tripathi
    Pathology
    University of South Carolina School of Medicine Columbia SC
  • YY Xing
    Pathology
    University of South Carolina School of Medicine Columbia SC
  • RC Tripathi
    Ophthalmology
    University of South Carolina School of Medicine Columbia SC
  • VA Pakalnis
    Ophthalmology
    University of South Carolina School of Medicine Columbia SC
  • KV Chalam
    Ophthalmology University of Florida Jacksonville FL
  • Footnotes
    Commercial Relationships   B.J. Tripathi, None; Y.Y. Xing, None; R.C. Tripathi, None; V.A. Pakalnis, None; K.V. Chalam, None. Grant Identification: Support: Vision Research Foundation
Investigative Ophthalmology & Visual Science December 2002, Vol.43, 4056. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      BJ Tripathi, YY Xing, RC Tripathi, VA Pakalnis, KV Chalam; Expression of -Interferon mRNA by Astrocytes . Invest. Ophthalmol. Vis. Sci. 2002;43(13):4056.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Abstract: : Purpose: To investigate whether astrocytes express the mRNA for γ-interferon, which is known to induce expression of nitric oxide synthase-2 by these cells. Methods: Astrocytes, cultured from the optic nerve of adult porcine eyes and plated onto the plastic substrate of a specially designed pressure chamber, were exposed to either an acute increase in hydrostatic pressure from 15 mm Hg to 40 mm Hg and sustained for 24 hrs, or to a gradual stepwise elevation of pressure from 15 mm Hg to 40 mm Hg over a period of 72 hrs. Astrocytes exposed to 15 mm Hg served as controls. In another set of experiments, confluent cultures of astrocytes were incubated for 6 hrs to 96 hrs in medium that contained tumor necrosis factor (TNF)-α at concentrations of 4, 8, 12, 16, or 20 ng/ml. Total RNA was extracted, reverse transcribed and amplified using primer pairs for γ-interferon and for GAPDH, as internal control. The PCR products were separated on 2% ethidium bromide gels for analysis. Results: Using primers specific for GAPDH, a single PCR-amplified product with the expected size of 258 bp was obtained from astrocytes exposed to increased hydrostatic pressure or incubated in TNF-α. The mRNA for γ-interferon was not detectable in astrocytes exposed to an acute or a gradually raised hydrostatic pressure from 15 mm Hg to 40 mm Hg or in control cells maintained at 15 mm Hg. Astrocytes incubated in TNF-α at concentrations of 4 to 20 ng/ml for 6 hrs up to 4 days did not express mRNA for γ-interferon. Conclusion: The excessive production of nitric oxide through the nitric oxide synthase-2 pathway by reactive astrocytes is believed have an important role in neurotoxicity of retinal ganglion cell axons in the optic nerve. Our results show that γ-interferon is neither expressed constitutively by astrocytes nor induced in these cells on exposure to hydrostatic pressure or TNF-α. The expression of γ-interferon by retinal ganglion cells in eyes with early glaucoma, which we have demonstrated previously, may be an initiating or contributing factor in the synthesis of nitric oxide by astrocytes.

Keywords: 380 cytokines/chemokines • 491 nitric oxide • 415 ganglion cells 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×