Bendotti C, Servadio A, Forloni G, Angeretti N, Samanin R
Laboratory of Neuropharmacology, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
Brain Res Mol Brain Res. 1990 Oct;8(4):343-8. doi: 10.1016/0169-328x(90)90048-i.
Neurons expressing the tryptophan hydroxylase (TPH) mRNA within the raphe nuclei of control rats showed a distribution similar to that observed using an antibody for TPH. Numerous packed cells expressing the TPH mRNA were observed in the ventral and dorsal zone of the nucleus raphe dorsalis (NDR) and in the pars dorsalis of the nucleus centralis superior (NCS) whereas fewer and more scattered neurons were found in the pars medialis of NCS. Five days after the intracerebroventricular injection of 5,7-dihydroxytryptamine (5,7-DHT), which markedly reduced the serotonin (5-HT) content in the hippocampus, caudate putamen and cortex, the hybridization signal had completely disappeared in the dorsal region of the NDR. In the ventromedial region, above and between the medial longitudinal fasciculus (MLF), which includes the pars dorsalis of NCS, there was a partial decrease of cell number and a marked increase of the grain density over spared neurons. No significant change was noted in the number of TPH-positive cells and hybridization signal in individual neurons of the pars medialis of NCS. Consistent with previous evidence of increased TPH activity in the residual 5-HT terminals, the present study shows that synthesis of the TPH mRNA may be augmented in some neurons surviving the lesion.
在对照大鼠中缝核内表达色氨酸羟化酶（TPH）mRNA的神经元呈现出与使用TPH抗体所观察到的分布相似的情况。在中缝背核（NDR）的腹侧和背侧区域以及中央上核（NCS）的背侧部观察到大量密集的表达TPH mRNA的细胞，而在NCS的内侧部则发现较少且分布更分散的神经元。在脑室内注射5,7 - 二羟基色胺（5,7 - DHT）五天后，海马、尾状壳核和皮质中的血清素（5 - HT）含量显著降低，NDR背侧区域的杂交信号完全消失。在腹内侧区域，在内侧纵束（MLF）上方及其中间，包括NCS的背侧部，细胞数量部分减少，而存活神经元上的颗粒密度显著增加。NCS内侧部单个神经元中TPH阳性细胞数量和杂交信号未观察到显著变化。与先前关于残余5 - HT终末中TPH活性增加的证据一致，本研究表明，在损伤后存活的一些神经元中，TPH mRNA的合成可能会增加。
