Effects of neonatal treatment with 6-aminonicotinamide on basal and isoproterenol-stimulated ornithine decarboxylase activity in cerebellum of the development rat.

Journal Article

6-Aminonicotinamide (6-AN) is a nicotinic acid (vitamin B3) antagonist which, when administered to immature animals, has a profound influence on brain development. To explore the biochemical mechanisms which underlie these actions, we evaluated effects of 6-aminonicotinamide on ornithine decarboxylase, an enzyme involved in cellular replication and differentiation. The cerebellum of the neonatal rat was chosen for study because it represents a brain region which undergoes major maturational events postnatally. When given to neonatal rats, 6-aminonicotinamide (10 mg/kg, i.p., on days 1, 3, 5 and 7) caused a prompt and persistent inhibition of the enzyme well in advance of adverse effects on tissue weight or on general growth. In addition, the ability of the cerebellum to respond to trophic stimulation by a beta-adrenergic agonist, isoproterenol, was attenuated markedly. Assessment of cerebellar morphology indicated an early adverse effect of 6-AN on granule' cell division, resulting in eventual disruption of the characteristic laminar structure of this brain region. These data support the view that reduced ornithine decarboxylase activity and impairment of its reactivity to growth stimuli participate in the toxic effects of 6-aminonicotinamide on brain development.

Full Text

Duke Authors

Cited Authors

  • Morris, G; Nadler, JV; Nemeroff, CB; Slotkin, TA

Published Date

  • September 15, 1985

Published In

Volume / Issue

  • 34 / 18

Start / End Page

  • 3281 - 3284

PubMed ID

  • 2931085

International Standard Serial Number (ISSN)

  • 0006-2952

Language

  • eng

Conference Location

  • England