Zhang X, Wahlström G, Nordberg A
Department of Pharmacology, Uppsala University, Sweden.
Int J Dev Neurosci. 1990;8(6):715-21. doi: 10.1016/0736-5748(90)90065-a.
The influence of development and aging on nicotinic receptor subtypes in rodent brain was investigated. 3H-nicotine and 3H-acetylcholine (3H-ACh) were used as receptor ligands. Specific binding sites for 3H-nicotine and 3H-ACh were detected in mouse brain during the late prenatal period. A drop in the number of 3H-nicotine and 3H-ACh binding sites was measured shortly after birth. The 3H-nicotine and 3H-ACh binding sites showed different time courses during prenatal development. Competition experiments using unlabelled (-)nicotine and 3H-nicotine revealed one population of high affinity nicotinic binding sites in the cortex of 1-day and 5-day-old mice whereas both a set of high and low affinity binding sites were found in adult mice. The proportion of cortical high and low affinity nicotinic binding sites did not change with aging although the absolute amount of high affinity nicotinic binding sites decreased. The 3H-nicotine binding showed different temperature dependence in rat brain of different ages. The results illustrate dynamic changes in nicotinic receptor properties during life span of rodents.
研究了发育和衰老对啮齿动物大脑中烟碱受体亚型的影响。使用³H-尼古丁和³H-乙酰胆碱（³H-ACh）作为受体配体。在产前后期小鼠大脑中检测到³H-尼古丁和³H-ACh的特异性结合位点。出生后不久，³H-尼古丁和³H-ACh结合位点的数量就出现下降。³H-尼古丁和³H-ACh结合位点在产前发育过程中表现出不同的时间进程。使用未标记的（-）尼古丁和³H-尼古丁进行的竞争实验显示，在1日龄和5日龄小鼠的皮质中有一群高亲和力烟碱结合位点，而在成年小鼠中则发现了一组高亲和力和低亲和力结合位点。尽管高亲和力烟碱结合位点的绝对数量减少，但皮质中高亲和力和低亲和力烟碱结合位点的比例并未随衰老而改变。³H-尼古丁结合在不同年龄大鼠大脑中表现出不同的温度依赖性。结果表明，在啮齿动物的生命周期中，烟碱受体特性存在动态变化。
