Differential Effects of Insulin on Choline Acetyltransferase and Glutamic Acid Decarboxylase Activities in Neuron‐Rich Striatal Cultures

B. J. Brass, D. Nonner, J. N. Barrett

Research output: Contribution to journalArticle

36 Scopus citations

Abstract

We studied the effects of insulin, nerve growth factor (NGF), and tetrodotoxin (TTX) on cellular metabolism and the activity of glutamic acid decarboxylase (GAD) and choline acetyltransferase (ChAT) in neuron-rich cultures prepared from embryonic day 15 rat striatum. Insulin (5 μg/ml) increased glucose utilization, protein synthesis, and GAD activity in cultures plated over a range of cell densities (2,800-8,400 cells/mm2). TTX reduced GAD activity; NGF had no effect on GAD activity. Insulin treatment reversibly reduced ChAT activity in cultures plated at densities of >4,000 cells/mm2, and the extent of this reduction increased with increasing cell density. The number of acetylcholinesterase-positive neurons was not reduced by insulin, suggesting that insulin acts by down-regulating ChAT rather than by killing cholinergic neurons. Insulin-like growth factor-1 (IGF-1) reduced ChAT activity at concentrations 10-fold lower than insulin, suggesting that insulin's effect on ChAT may involve the IGF-1 receptor. NGF increased ChAT activity; TTX had no effect on ChAT activity. These results suggest that striatal cholinergic and GA-BAergic neurons are subject to differential trophic control.

Original languageEnglish (US)
Pages (from-to)415-424
Number of pages10
JournalJournal of neurochemistry
Volume59
Issue number2
DOIs
StatePublished - Aug 1992

Keywords

  • Choline acetyltransferase activity
  • Glutamic acid decarboxylase activity
  • Insulin
  • Insulin-like growth factor-1
  • Neuronal culture
  • Striatum

ASJC Scopus subject areas

  • Biochemistry
  • Cellular and Molecular Neuroscience

Fingerprint Dive into the research topics of 'Differential Effects of Insulin on Choline Acetyltransferase and Glutamic Acid Decarboxylase Activities in Neuron‐Rich Striatal Cultures'. Together they form a unique fingerprint.

  • Cite this