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Alterations in CNS amine levels by acclimatization to hypobaric hypoxia
Brain Research Bulletin
|August 1, 1983
Summary
Simulated high altitude (SHA) exposure in rabbits reduced dopamine turnover in the brain. Norepinephrine levels in the midbrain also decreased, suggesting neurochemical adaptations to hypobaric hypoxia.
Area of Science:
- Neuroscience
- Altitude Physiology
Background:
- High altitude environments present challenges to mammalian physiology.
- Understanding neurochemical changes during acclimatization is crucial for adaptation research.
Purpose of the Study:
- To investigate the effects of simulated high altitude (SHA) exposure on neurotransmitter levels in rabbits.
- To determine if rabbits exhibit similar neurochemical responses to hypobaric hypoxia as other species.
Main Methods:
- Rabbits were exposed to simulated high altitude (6000 M, 350 torr) on alternate days for 70 days.
- Neurotransmitter levels, including norepinephrine (NE), dopamine (DA), and DOPAC, were measured in brain regions.
- Control and acclimatized groups were compared for significant differences.
Main Results:
- Acclimatized rabbits showed lower midbrain norepinephrine levels compared to controls (p<0.06).
- Striatal DOPAC levels were significantly higher in control rabbits than in SHA rabbits (p<0.04).
- Striatal dopamine levels were higher in SHA rabbits, and the DOPAC/DA ratio was lower (0.4 vs 2.0), indicating reduced dopamine turnover.
Conclusions:
- Simulated high altitude exposure in rabbits leads to reduced dopamine turnover in the striatum.
- Norepinephrine levels in the midbrain are also affected by SHA acclimatization in rabbits.
- Observed species differences in neurochemical responses to hypobaric hypoxia may exist between rabbits and rats.
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