Opioid-dependent growth of glial cultures: Suppression of astrocyte DNA synthesis by met-enkephalin

doi:10.1016/0024-3205(90)90041-O

Life Sciences

Volume 46, Issue 2, 1990, Pages 91-98

https://doi.org/10.1016/0024-3205(90)90041-O Get rights and content

Abstract

The action of met-enkephalin on the growth of astrocytes in mixed-glial cultures was examined. Primary, mixed-glial cultures were isolated from 1 day-old mouse cerebral hemispheres and continuously treated with either basal growth media (controls), 1 μM)met-enkephalin plus the opioid antagonist naloxone (3 μM), or naloxone alone (3 μM). Absolute numbers of neural cells were counted in unstained preparations, while combined [³H]-thymidine autoradiography and glial fibrillary acid protein (GFAP) immunocytochemistry was performed to identify specific changes in astrocytes. When compared to control and naloxone treated cultures, met-enkephalin caused a significant decrease in both total cell numbers, and in [³H--thymidine incorporation by GFAP-positive cells with flat morphology. These results indicate that met-enkephalin suppresses astrocyte growth in culture.

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Opioid-dependent growth of glial cultures: Suppression of astrocyte DNA synthesis by met-enkephalin

Abstract

J. Pediatr.

Dev. Brain Res.

Life Sci.

Brain Res.

Dev. Brain. Res.

Brain Res.

Dev. Brain Res.

Life Sci.

Brain Res.

Brain Res. Bull.

Brain Res.

Neurosci. Lett.

Brain Res. Bull.

Dev. Brain Res.

Int. Rev. Neurobiol.

Brain Res.