Farmacología Conductual, Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, México City, Mexico.
Eur J Pharmacol. 2010 May 10;633(1-3):39-43. doi: 10.1016/j.ejphar.2010.01.022. Epub 2010 Feb 1.
It has been suggested that old depressed patients require longer antidepressant treatments than their young counterparts. The objective of this study was to establish if aging impairs the response to an antidepressant by using an animal model. For this purpose, young and middle-aged male Wistar rats (of around 4 and 14months, respectively) were exposed to a chronic mild stress schedule for 3weeks. After this period, the animals that developed anhedonia, reflected as a reduction in sucrose solution (1%) intake, were treated with citalopram (10mg/kg/day) during 21days while still maintained under the chronic mild stress schedule. Non-stressed animals were included as controls. In young rats citalopram reversed the reduction in sucrose consumption induced by chronic mild stress after one week of treatment, while in middle-aged animals a similar reversion occurred after three weeks. Citalopram did not importantly modify simple water intake in stressed animals or sucrose consumption in non-stressed rats of both ages. The results imply that young rats have a lower latency of onset to the antidepressant-like effect of citalopram than middle-aged animals. The lower sensitivity of middle-aged animals to citalopram could be underlied by their lower levels of gonadal hormones.
有人认为老年抑郁患者需要比年轻患者更长时间的抗抑郁治疗。本研究的目的是通过动物模型确定衰老是否会影响抗抑郁药的反应。为此，将年轻和中年雄性 Wistar 大鼠（分别约为 4 个月和 14 个月）暴露于慢性轻度应激方案 3 周。经过这段时间，出现快感缺失的动物（表现为蔗糖溶液（1%）摄入量减少）在仍处于慢性轻度应激方案下的同时接受西酞普兰（10mg/kg/天）治疗 21 天。未受压力的动物被包括作为对照。在年轻大鼠中，西酞普兰在治疗一周后逆转了慢性轻度应激引起的蔗糖消耗减少，而在中年动物中，类似的逆转发生在三周后。西酞普兰对应激动物的简单水摄入量或两个年龄段非应激大鼠的蔗糖消耗没有重要影响。研究结果表明，年轻大鼠对西酞普兰的抗抑郁样作用的潜伏期比中年动物短。中年动物对西酞普兰的敏感性较低可能是由于其性腺激素水平较低所致。
