Biochemical and radiohistochemical analyses of alpha-2 adrenergic receptors in the kindling model of epilepsy.

Published

Journal Article

Biochemical and radiohistochemical methods were used to study alterations in alpha-2 adrenergic receptors in the kindling model of epilepsy. The radioligands used for antagonist and agonist binding were [3H]idazoxan and [3H]p-aminoclonidine, respectively. Radioligand binding to membranes isolated from eight brain regions disclosed a small (14%) but statistically significant reduction in [3H]idazoxan binding in a single area, amygdala-pyriform-entorhinal cortex. This was confirmed by a larger (25%) reduction (P less than .02) in agonist binding in the same region. These reductions were present in animals sacrificed 1 day, but not 2 weeks, after the last kindled seizure. Quantitative radiohistochemical studies identified a bilaterally symmetric reduction of approximately 20% of [3H]p-aminoclonidine binding in the pyriform cortex and the central, medial and lateral amygdaloid nuclei. No significant differences were detected in nine other structures. We propose that the reduction in alpha-2 receptor binding contributes in part to the reduced sensitivity of pyriform cortex neurons of kindled animals to the inhibitory effects of alpha 2 agonists. The reduced alpha-2-receptor binding may also underlie a transient attenuation of alpha-2 receptor-mediated neuro-transmission and thereby constitute one mechanism contributing to kindling development.

Full Text

Duke Authors

Cited Authors

  • Chen, LS; Weingart, JB; McNamara, JO

Published Date

  • June 1, 1990

Published In

Volume / Issue

  • 253 / 3

Start / End Page

  • 1272 - 1277

PubMed ID

  • 1972752

Pubmed Central ID

  • 1972752

International Standard Serial Number (ISSN)

  • 0022-3565

Language

  • eng

Conference Location

  • United States