N-acetylaspartate to total creatine ratio in the hippocampal CA1 sector after transient cerebral ischemia in gerbils: influence of neuronal elements, reactive gliosis, and tissue atrophy.

Abstract

The authors compared temporal profiles of N-acetylaspartate (NAA) and the NAA/total creatine ratio with neuronal and astrocytic densities and with tissue atrophy in the hippocampal CA1 sector of gerbils after 5-minute bilateral forebrain ischemia and subsequent reperfusion for up to 6 months. The CA1 sector was dissected from 20- micro m lyophilized sections (n = 5) for NAA, phosphocreatine, and creatine assays using high-performance liquid chromatography. Adjacent 10- micro m sections were used for immunohistochemical analysis to follow neuronal and astrocytic responses. The NAA concentration was significantly (P<0.01) decreased after 7 days but leveled off thereafter. The NAA/total creatine (phosphocreatine + creatine) ratio was significantly decreased after 7 days and further decreased (P<0.05) after 6 months. Extensive neuronal damage developed beyond 7 days, while reactive astrogliosis progressed throughout the observation period. There was a good linear correlation (P<0.01) between astroglial density and the NAA/total creatine ratio beyond 7 days. The thickness of the CA1 sector was significantly reduced after 1 month and further reduced after 6 months. Although both NAA level and the NAA/total creatine ratio seemed to be indicators of neuronal damage, the latter could be influenced by reactive astrogliosis with progression of tissue atrophy.

• Authors: Kuni Konaka, Hirokazu Ueda, Ji-Yao Li, Masayasu Matsumoto, Saburo Sakoda, Takehiko Yanagihara
• Journal: Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism (J Cereb Blood Flow Metab) Vol. 23 Issue 6 Pg. 700-8 (Jun 2003) ISSN: 0271-678X [Print] United States
• PMID: 12796718 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Aspartic Acid
• N-acetylaspartate
• Creatine

Topics

• Animals
• Aspartic Acid (analogs & derivatives, metabolism)
• Astrocytes (metabolism, pathology)
• Atrophy
• Cell Count
• Common Variable Immunodeficiency
• Creatine (metabolism)
• Gerbillinae
• Gliosis (metabolism, pathology)
• Hippocampus (metabolism, pathology)
• Ischemic Attack, Transient (metabolism, pathology)
• Male
• Neurons (metabolism, pathology)
• Reperfusion Injury (metabolism, pathology)