Wenk G L, Engisch K L
J Neurochem. 1986 Sep;47(3):845-50. doi: 10.1111/j.1471-4159.1986.tb00688.x.
The response of the serotonergic system following injury to the basal forebrain cholinergic system was investigated in rats. The density of 5-hydroxytryptamine (serotonin) type 2 (S2) receptor sites in the frontal cortex and hippocampus was determined 1 week and 4 months after production of lesions by injections of ibotenic acid into the medial septum and nucleus basalis magnocellularis. One week later, the number of S2 receptor sites in the frontal neocortex, as defined by [3H]ketanserin binding, was unchanged. Four months later, the number of [3H]ketanserin binding sites (and Bmax) was increased and high-affinity [3H]serotonin uptake was decreased in the frontal neocortex, but not in the hippocampus, relative to unlesioned controls. Choline acetyltransferase (acetyl-CoA:choline O-acetyltransferase; EC 2.3.1.6) activity was decreased significantly in the frontal neocortex and hippocampus 1 week and 4 months after surgery. The change in frontal neocortical S2 receptor site density was inversely related to the level of choline acetyltransferase activity, was specific for cholinergic denervation associated with the cortex but not the hippocampus, and may represent a localized denervation supersensitivity due to degeneration of median raphe cortical afferents.
在大鼠中研究了基底前脑胆碱能系统损伤后5-羟色胺能系统的反应。通过向内侧隔区和大细胞基底核注射鹅膏蕈氨酸制造损伤，在损伤后1周和4个月测定额叶皮质和海马中5-羟色胺（血清素）2型（S2）受体位点的密度。1周后，由[3H]酮色林结合所定义的额叶新皮质中S2受体位点的数量未发生变化。4个月后，相对于未损伤的对照，额叶新皮质中[3H]酮色林结合位点的数量（及Bmax）增加，高亲和力[3H]血清素摄取减少，但海马中未出现这种情况。术后1周和4个月，额叶新皮质和海马中的胆碱乙酰转移酶（乙酰辅酶A：胆碱O-乙酰转移酶；EC 2.3.1.6）活性显著降低。额叶新皮质中S2受体位点密度的变化与胆碱乙酰转移酶活性水平呈负相关，对与皮质而非海马相关的胆碱能去神经支配具有特异性，并且可能代表中缝核皮质传入纤维变性导致的局部去神经超敏反应。
