Bendotti C, Servadio A, Samanin R
Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
J Neurosci. 1991 Mar;11(3):600-7. doi: 10.1523/JNEUROSCI.11-03-00600.1991.
Using in situ hybridization, we examined the distribution of the mRNA encoding for the growth-associated protein GAP-43 in the brain stem of adult rats. GAP-43 was expressed at the highest level in the nucleus raphe dorsalis (NDR), nucleus centralis superior (NCS), substantia nigra compacta (SNc), ventral tegmental area (VTA), and locus coeruleus (LC). An intermediate level of signal was detected over the periaque-ductal gray, superior colliculi, and thalamic region, and no significant signal was detected in the substantia nigra pars reticulata and red nucleus. The hybridization signals of GAP-43 mRNA and tryptophan hydroxylase mRNA completely overlapped in the NDR and NCS, and signals for GAP-43 mRNA and tyrosine hydroxylase mRNA overlapped in the SNc, VTA, and LC. The disappearance of the hybridization signal for GAP-43 mRNA after intracerebroventricular injections of the neurotoxins 5,7-dihydroxytryptamine (5,7-DHT) or 6-hydroxydopamine (6-OHDA) indicated that high levels of GAP-43 are synthesized in the serotonergic neurons of the raphe nuclei and in the catecholaminergic neurons of the SNc, VTA, and LC. In light of the role of GAP-43 in axonal outgrowth, modulation of signal transduction, and release of different neurotransmitters in the adult CNS, this phosphoprotein might be involved in the functional plasticity and synaptic transmission of monoaminergic neurons.
我们运用原位杂交技术，检测了成年大鼠脑干中编码生长相关蛋白GAP - 43的mRNA的分布情况。GAP - 43在中缝背核（NDR）、中央上核（NCS）、黑质致密部（SNc）、腹侧被盖区（VTA）和蓝斑（LC）中表达水平最高。在导水管周围灰质、上丘和丘脑区域检测到中等水平的信号，而在黑质网状部和红核中未检测到明显信号。GAP - 43 mRNA与色氨酸羟化酶mRNA的杂交信号在NDR和NCS中完全重叠，GAP - 43 mRNA与酪氨酸羟化酶mRNA的信号在SNc、VTA和LC中重叠。脑室内注射神经毒素5,7 - 二羟基色胺（5,7 - DHT）或6 - 羟基多巴胺（6 - OHDA）后，GAP - 43 mRNA的杂交信号消失，这表明在中缝核的5 - 羟色胺能神经元以及SNc、VTA和LC的儿茶酚胺能神经元中高水平合成GAP - 43。鉴于GAP - 43在轴突生长、信号转导调节以及成年中枢神经系统中不同神经递质释放方面的作用，这种磷蛋白可能参与单胺能神经元的功能可塑性和突触传递。
