Hashizume K
Neuroendocrinology. 1976;20(1):47-58. doi: 10.1159/000122468.
L-Dihydroxphenylalanine (L-DOPA) significantly inhibited intrathyroidal colloid droplet formation induced by exposure to cold in the rat. Diethyldithiocarbamate (DDC) also inhibited colloid droplet formation in response to cold. The combined administration of L-DOPA and DDC produced an additive inhibition of the thyroidal endocytotic response to exposure to cold. Pretreatment with chlorpromazine (CPZ) ameliorated the inhibitory effect of L-DOPA. DL-alpha-methyl-p-tyrosine (alpha-MT) also signficantly depressed the thyroidal response. Inhibition of colloid droplet formation induced by alpha-MT was not altered by the administration of DL-dihydroxyphenylserine (DL-DOPS). On the other hand, treatment of the alpha-MT-treated rats with L-DOPA to normalize dopamine synthesis resulted in a dramatic recovery from the inhibition. Blockade of serotonin biosynthesis with p-chlorophenylalanine (p-CPA) failed to produce a significant inhibition of colloid droplet formation. However, 5-hydroxytryptophan (5-HTP) markedly inhibited the thyroidal response to cold. Brocresine phosphate (BP) was another inhibitor of the thyroidal endocytotic response to exposure to cold. Oxotremorine also markedly depressed the thyroidal response to cold. Since these drugs did not interfere with pituitary thyroid responsiveness to exogenous thyrotropin-releasing hormone (TRH), it seems that the throidal endocytotic response to exposure to cold as a reflection of TSH secretion was directly influenced by alterations of brain biogenic amine concentrations or turnover rates.
L-二羟基苯丙氨酸（L-DOPA）显著抑制大鼠因暴露于寒冷环境而诱导的甲状腺内胶体滴形成。二乙基二硫代氨基甲酸盐（DDC）也抑制因寒冷引起的胶体滴形成。联合给予L-DOPA和DDC对甲状腺对寒冷暴露的内吞反应产生了相加性抑制作用。用氯丙嗪（CPZ）预处理可改善L-DOPA的抑制作用。DL-α-甲基-p-酪氨酸（α-MT）也显著降低甲状腺反应。DL-二羟基苯丝氨酸（DL-DOPS）的给药并未改变α-MT诱导的胶体滴形成抑制作用。另一方面，用L-DOPA治疗α-MT处理的大鼠以使多巴胺合成正常化，导致抑制作用显著恢复。用对氯苯丙氨酸（p-CPA）阻断5-羟色胺生物合成未能产生对胶体滴形成的显著抑制作用。然而，5-羟色氨酸（5-HTP）显著抑制甲状腺对寒冷的反应。磷酸布罗克辛（BP）是另一种对寒冷暴露的甲状腺内吞反应的抑制剂。氧化震颤素也显著降低甲状腺对寒冷的反应。由于这些药物不干扰垂体对外源性促甲状腺激素释放激素（TRH）的甲状腺反应性，似乎甲状腺对寒冷暴露的内吞反应作为促甲状腺激素分泌的反映，直接受到脑生物胺浓度或周转率改变的影响。
