The enzyme tyrosine hydroxylase (TH) is broadly expressed in catecholaminergic neurons. In the spinal cord, four components contain TH, including A11 diencephalospinal dopaminergic (DA-ergic) pathways, intraspinal DA-related neurons, supraspinal noradrenergic projections, and afferents of TH-expressing sensory neurons. A human TH-enhanced green fluorescent protein (hTH-eGFP) transgenic rat was recently developed to tag TH+ profiles in the nervous system for visualization. Using immunostaining, we found that only A11 pathways express GFP whereas the other 3 components do not in the spinal cord. Thus, this may suggest a genetic difference among these TH+ elements even though they produce the same protein.

中文翻译：

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hTH-eGFP 大鼠脊髓内的转基因表达

酪氨酸羟化酶 (TH) 在儿茶酚胺能神经元中广泛表达。在脊髓中，四种成分包含 TH，包括 A11 间脑脊髓多巴胺能 (DA-ergic) 通路、脊髓内 DA 相关神经元、脊髓上去甲肾上腺素能投射和表达 TH 的感觉神经元的传入。最近开发了一种人类 TH 增强型绿色荧光蛋白 (hTH-eGFP) 转基因大鼠，用于标记神经系统中的 TH+ 轮廓以进行可视化。使用免疫染色，我们发现只有 A11 通路表达 GFP，而其他 3 个成分不在脊髓中。因此，这可能表明这些 TH+ 元件之间存在遗传差异，即使它们产生相同的蛋白质。