EFFECTS OF LIGHT ON DOPAMINE METABOLISM IN THE CHICK RETINA
EFFECTS OF LIGHT ON DOPAMINE METABOLISM IN THE CHICK RETINA
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DOI：
10.1111/j.1471-4159.1983.tb12650.x
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发表时间：
1983-01-01
影响因子：
4.7
通讯作者：
RANDO, RR
中科院分区：
文献类型：
--
作者：
PARKINSON, D;RANDO, RR
研究了长时间光照对鸡视网膜多巴胺能神经元活动和多巴胺（DA）代谢的影响。α-氟甲基多巴，一种有效的和特定的芳香族氨基酸脱羧酶的不可逆灭活剂，被用来评估DA营业额抑制合成后，也评估体内酪氨酸羟化酶活性的二羟基苯丙氨酸积累。在48小时的光暴露后，12日龄小鸡的视网膜DA为约二羟苯乙酸（DOPAC）和高香草酸（HVA）的含量升高2-3倍（P < 0.005）。DA的营业额是... 2-在光照下（t1/2 [半衰期] = 31 min）比在黑暗中（t1/2 = 65 min）快一倍。酪氨酸羟化酶，在体外用饱和水平的辅因子和底物测定，增加了约50%的光暴露后。体内表观酪氨酸羟化酶活性为apprx。6-比黑暗中高出一倍。这些结果的解释和讨论的DA合成的调节和使用DOPAC和HVA的DA功能在视网膜中的指数。
The effect of prolonged exposure to light on the activity of dopaminergic neurons and dopamine (DA) metabolism of chick retinae was investigated. .alpha.-Fluoromethyldopa, a potent and specific irreversible inactivator of aromatic amino acid decarboxylase, was used to assess DA turnover after inhibition of synthesis and also to assess in vivo tyrosine hydroxylase activity by dihydroxyphenylalanine accumulation. After 48 h of light exposure, retinal DA in 12-day-old chicks was .apprx. 30% higher (P < 0.005); dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were elevated 2-3 times (P < 0.005) the level of controls kept in the dark for the same period. DA turnover was .apprx. 2-fold faster in the light (t1/2 [half time] = 31 min) than in the dark (t1/2 = 65 min). Tyrosine hydroxylase, assayed in vitro with saturating levels of cofactor and substrate, increased by .apprx. 50% after light exposure. The apparent tyrosine hydroxylase activity in vivo was .apprx. 6-fold higher in the light than the dark. These results are interpreted and discussed in terms of the regulation of DA synthesis and the use of DOPAC and HVA as indices of DA function in the retina.