Thyrotropin releasing hormone prevents abnormalities of cortical acetylcholine and monoamines in mice following head injury

Ken Ichi Tanaka, Norio Ogawa, Masato Asanuma, Yoichi Kondo

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We investigated the effects of thyrotropin releasing hormone (TRH) on changes in cortical concentrations of acetylcholine (ACh) and monoamines produced by concussion in mice. Concussion was induced by dropping a metal rod on the head, and the concentration of ACh, norepinephrine (NE), dopamine (DA) and serotonin (5-HT) in the cerebral cortex were measured by HPLC. We also examined the arousal effects of 0.5 mg/kg of TRH and 0.015 mg/kg of L- pyro-2-aminoadipyl-histidyl-thiazolidine-4-carboxamide (MK-771), a TRH analogue, injected intraperitoneally 10 min before concussion, on neurotransmitter concentrations. Mice were sacrificed at 25 (representing the righting reflex time) and 210 s (representing spontaneous movement time). At 25 s after concussion, the concentration of ACh was significantly higher than in control mice, but pretreatment with TRH and MK-771 prevented the rise in ACh. In contrast, head injury significantly reduced NE concentration. TRH and MK-771 also prevented the fall in NE. Concussion did not change cortical concentrations of DA and 5-HT. Our results suggest that disturbances of consciousness produced by concussion may be due to increased ACh and diminished NE in the cerebral cortex. Our findings also suggest that the arousal effects of TRH on concussion-induced disturbances of consciousness are due to normalization of cortical cholinergic and noradrenergic neuronal systems.

Original languageEnglish
Pages (from-to)173-178
Number of pages6
JournalRegulatory Peptides
Volume70
Issue number2-3
DOIs
Publication statusPublished - Jun 18 1997

Keywords

  • Acetylcholine
  • Cerebral cortex
  • Dopamine
  • Head injury
  • Mice
  • Norepinephrine
  • TRH

ASJC Scopus subject areas

  • Biochemistry
  • Physiology
  • Endocrinology
  • Clinical Biochemistry
  • Cellular and Molecular Neuroscience

Fingerprint Dive into the research topics of 'Thyrotropin releasing hormone prevents abnormalities of cortical acetylcholine and monoamines in mice following head injury'. Together they form a unique fingerprint.

  • Cite this