Effects of Hypoxia on the Activity of the Dopaminergic Neuron System in the Rat Striatum as Studied by In Vivo Brain Microdialysis

  title={Effects of Hypoxia on the Activity of the Dopaminergic Neuron System in the Rat Striatum as Studied by In Vivo Brain Microdialysis},
  author={Yoshinori Akiyama and Kunio Koshimura and Tetsuya Ohue and K. Lee and Soichi Miwa and Sen Yamagata and Haruhiko Kikuchi},
  journal={Journal of Neurochemistry},
The purpose of the present study is to clarify the effects of hypoxia on the activity of the dopaminergic neurons in the brain and its mechanism of action. For this purpose, the effects of hypoxia on the extracellular levels of 3,4‐dihy‐droxyphenylethylamine (dopamine) were examined in the rat Striatum using in vivo brain microdialysis in the presence or absence of pretreatment with either tetrodotoxin (a blocker of voltage‐dependent sodium channels) or nomifensine (a blocker of dopamine… 
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Effects of Choline Administration on In Vivo Release and Biosynthesis of Acetylcholine in the Rat Striatum as Studied by In Vivo Brain Microdialysis
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Effect of Decreased Oxygen on In Vitro Release of Endogenous 3,4‐Dihydroxyphenylethylamine from Mouse Striatum
Regardless of exogenous DA, hypoxia and anoxia increased extracellular DA, which may play a role in ischemic cell damage, and the amount of DA added to the media was critical; in the presence of high concentrations of DA, anoxial reduced reuptake.
Differential effects of hypoxia on the turnover of norepinephrine and epinephrine in the heart, adrenal gland, submaxillary gland and stomach.
The results show that the effects of hypoxia on the activities of the sympathoadrenal system differ depending on the organs; activities are increased in the heart and adrenal gland, decreased in the submaxillary gland and unchanged in the stomach.
Neurotransmitter Metabolism in Rat Brain Synaptosomes: Effect of Anoxia and pH
Responses of synaptosomes to anaerobiosis are remarkably similar to the behavior of intact brain in hypoxia and ischemia, and neurotransmitter uptake systems are more sensitive to short periods of anaerOBiosis than are either the energy metabolism or ion transport.
Enhancement of Dopamine Release In Vivo from the Rat Striatum by Dialytic Perfusion of 6R‐l‐erythro‐5,6,7,8‐Tetrahydrobiopterin
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Enhancement of In Vivo Tyrosine Hydroxylation in the Rat Adrenal Gland Under Hypoxic Conditions
In vivo tyrosine hydroxylation is enhanced under hypoxia, although availability of oxygen is reduced, and this enhancement is the result of both an increase in tyosine content coupled with increased sensitivity of TH to changes in tyOSine tissue content and of an increased in dependence of TH on tyrosines levels.