The possible involvement of tetrodotoxin-sensitive ion channels in ischemic neuronal damage in the rat hippocampus.

Abstract

To determine the role of tetrodotoxin-sensitive ion channels in post-ischemic selective neuronal death, the effect of tetrodotoxin on ischemia-induced brain cell injury was studied in rats. The animals were subjected to 20 min of cerebral ischemia in a four vessels occlusion model. Thirty min before ischemia, tetrodotoxin at a dose of 10(-7) or 10(-6) M was topically applied into the hippocampal CA1 subfield. Morphological changes in the CA1 subfield were evaluated 7 days after ischemia and compared with those of a vehicle-injected group. The average cell density of CA1 pyramidal neurons ipsilateral to the injection (cells/mm, mean +/- S.E.M.) was 27 +/- 7 (n = 6) in the vehicle-treated group, and 56 +/- 13 (n = 6) and 83 +/- 17 (n = 6) in the group treated with tetrodotoxin at doses of 10(-7) and 10(-6) M, respectively. Tetrodotoxin mitigated the ischemic hippocampal neuronal damage in a limited but dose-dependent manner. This suggests that activation of tetrodotoxin-sensitive ion channels might contribute to the process of the ischemic neuronal damage.

• Authors: Y Yamasaki, K Kogure, H Hara, H Ban, N Akaike
• Journal: Neuroscience letters (Neurosci Lett) Vol. 121 Issue 1-2 Pg. 251-4 (Jan 02 1991) ISSN: 0304-3940 [Print] Ireland
• PMID: 1708482 (Publication Type: Journal Article)

Chemical References

• Ion Channels
• Tetrodotoxin

Topics

• Animals
• Brain Ischemia (complications, pathology)
• Hippocampus (pathology)
• Ion Channels (drug effects)
• Male
• Nervous System Diseases (etiology, pathology)
• Pyramidal Tracts (cytology, pathology)
• Rats
• Rats, Inbred Strains
• Tetrodotoxin (toxicity)