Mason G A, Bondy S C, Nemeroff C B, Walker C H, Prange A J
Department of Psychiatry, University of North Carolina, Chapel Hill 27514.
Psychoneuroendocrinology. 1987;12(4):261-70. doi: 10.1016/0306-4530(87)90050-3.
The effects of hyperthyroidism or hypothyroidism, alone or in combination with the tricyclic antidepressant desmethylimipramine (DMI), on brain beta-adrenergic and serotonin (5HT2) receptors were studied in adult male Sprague-Dawley rats. Intraperitoneal administration of T3 or T4 for 7 days increased the number of cortical beta-adrenergic and 5HT2 receptors. These increases were significant at levels of 250 micrograms/kg or above for both hormones. Neither thyroidectomy nor "reverse" T3 (rT3) (500 micrograms/kg) produced an effect on either receptor type. The down-regulation of beta-adrenergic receptors produced by daily subcutaneous injections of 20 mg/kg of DMI for 7 days was partially offset by concurrent administration of T4, whereas the down-regulation of 5HT2 receptors produced by the drug was not affected by concurrent administration of either T3 or T4. Hypothyroidism (thyroidectomy) did not significantly affect the adaptation of these receptor populations to DMI. As regards brain regions other than cortex, T4 (250 micrograms/kg) produced the same changes in hippocampus as in cortex, while thyroidectomy decreased beta-adrenergic receptors only in the cerebellum. Thyroxine also elevated 5HT2 receptors in the hippocampus; thyroidectomy caused a significant decrease in 5HT2 receptors in the striatum.
在成年雄性斯普拉格 - 道利大鼠中，研究了甲状腺功能亢进或减退单独或与三环类抗抑郁药去甲丙咪嗪（DMI）联合使用对脑β - 肾上腺素能和5 - 羟色胺（5HT2）受体的影响。腹腔注射T3或T4 7天可增加皮质β - 肾上腺素能和5HT2受体的数量。两种激素在250微克/千克及以上水平时，这些增加均具有显著性。甲状腺切除术和“反式”T3（rT3）（500微克/千克）对这两种受体类型均无影响。每日皮下注射20毫克/千克DMI，连续7天导致的β - 肾上腺素能受体下调，可因同时给予T4而部分抵消，而该药物导致的5HT2受体下调不受同时给予T3或T4的影响。甲状腺功能减退（甲状腺切除术）对这些受体群体对DMI的适应性没有显著影响。至于皮质以外的脑区，T4（250微克/千克）在海马体中产生的变化与在皮质中相同，而甲状腺切除术仅使小脑中的β - 肾上腺素能受体减少。甲状腺素还使海马体中的5HT2受体升高；甲状腺切除术导致纹状体中的5HT2受体显著减少。
