Changes in rat striatum catecholamine during hypoxia with reference to protective effects of flunarizine.

Abstract

We investigated the changes in dopamine, homovanillic acid, 3,4-dihydroxyphenylacetic acid, and norepinephrine content in striatum of rats ventilated with 5% oxygen in nitrogen gas. We also examined the effects of flunarizine, a calcium channel blocker, on these catecholamine levels. During 10-20 min. of hypoxia, the dopamine content gradually increased and the 3,4-dihydroxyphenylacetic acid and norepinephrine levels decreased, while the concentration of homovanillic acid remained unchanged. The concentrations of these substances subsequently returned to control values after 4 hr of room air breathing. In animals pretreated with intravenous flunarizine injection, there was a slight increase in dopamine, with no appreciable change in homovanillic acid or 3,4-dihydroxyphenylacetic acid content during 10-20 min. of hypoxia. The decrease in norepinephrine which occurred during 10-20 min. of hypoxia was identical between non-treated and flunarizine-treated animals. Catecholamine levels subsequently returned to control values after 4 hr of room air breathing. These results suggest that flunarizine minimizes the alterations in striatal catecholamine contents during hypoxic ventilation.

• Authors: M Yamazaki, T Masuda, Y Ito, S Kuze, Y Momose
• Journal: Pharmacology & toxicology (Pharmacol Toxicol) Vol. 70 Issue 4 Pg. 294-8 (Apr 1992) ISSN: 0901-9928 [Print] Denmark
• PMID: 1608916 (Publication Type: Journal Article)

Chemical References

• Catecholamines
• Solvents
• Flunarizine
• Oxygen

Topics

• Animals
• Blood Gas Analysis
• Catecholamines (metabolism)
• Corpus Striatum (metabolism)
• Flunarizine (pharmacology)
• Hemodynamics (drug effects)
• Hypoxia (metabolism)
• Male
• Oxygen (pharmacology)
• Rats
• Rats, Inbred Strains
• Solvents
• Survival Rate