Tychsen L, Sitaram N
Ophthalmology Branch, United States Air Force School of Aerospace Medicine, Brooks Air Force Base, San Antonio, TX.
Ann Neurol. 1989 May;25(5):444-9. doi: 10.1002/ana.410250505.
To determine the effect of catecholamine depletion on ocular motor pathways in humans, we studied the eye movements of 3 normal subjects who received the drug metyrosine (alpha-methylparatyrosine). This drug temporarily depleted dopamine and norepinephrine, as measured by a reduction in the metabolite, 3-methoxy-4-hydroxy-phenylethyleneglycol (MHPG). Saccadic, pursuit, and vestibulo-ocular eye movements were recorded using infrared oculography with subjects both on placebo and on metyrosine. The most consistent effect observed with metyrosine was an increase in the amplitude and frequency of saccadic intrusions during fixation and pursuit. Two of the 3 subjects also had shortened time constants for the vestibulo-ocular reflex, attributable in part to the sedative effect of catecholamine depletion. The increase in saccadic intrusions implies that catecholamines modulate the activity of a subpopulation of suppressor motor neurons in the human brainstem.
为了确定儿茶酚胺耗竭对人类眼球运动通路的影响，我们研究了3名接受药物甲酪氨酸（α-甲基对酪氨酸）的正常受试者的眼球运动。通过代谢物3-甲氧基-4-羟基苯乙二醇（MHPG）的减少来测量，该药物暂时耗尽了多巴胺和去甲肾上腺素。使用红外眼动图记录了受试者在服用安慰剂和甲酪氨酸时的扫视、追踪和前庭眼动。服用甲酪氨酸观察到的最一致的效果是在注视和追踪期间扫视侵入的幅度和频率增加。3名受试者中有2名的前庭眼反射时间常数也缩短了，部分原因是儿茶酚胺耗竭的镇静作用。扫视侵入的增加意味着儿茶酚胺调节了人类脑干中抑制性运动神经元亚群的活动。
