Halász N, Ljungdahl A, Hökfelt T, Johansson O, Goldstein M, Park D, Biberfeld P
Brain Res. 1977 May 13;126(3):455-74. doi: 10.1016/0006-8993(77)90597-2.
The rat olfactory bulb was studied at the light and electron microscopic level with the indirect immunofluorescence technique and the unlabelled antibody enzyme method (PAP-technique), respectively. Antibodies to all 4 enzymes in the catecholamine synthesis were used. In the principal bulb the first two enzymes, tyrosine hydroxylase (TH) and DOPA decarboxylase (DDC), but not dopamine-beta-hydroxylase (DBH), were present in a proportion of periglomerular cell bodies and dendrites indicating that these neurons synthesize dopamine (DA). This amine may therefore be released as a transmitter substance at some of the intraglomerular dendrodendritic synapses which periglomerular cells form with the mitral cells. There is evidence to suggest that some periglomerular cells use GABA as their transmitter. Thus, a morphologically and physiologically homogenous population of neurons can be subdivided on the basis of transmitter histochemical criteria. There was an impression of more DDC-positive than TH-positive fibers in the glomeruli. Such presumably DDC-positive, but TH-negative processes may represent 5-hydroxytryptamine (5-HT) nerve terminals. DBH-positive fibers were seen in the granular, external plexiform, and very rarely, in the glomerular layers, probably representing noradrenaline (NA) nerve terminals ascending from the lower brain stem. Weakly fluorescent DDC-positive fibers may represent nerve terminals of ascending 5-HT neurons. No phenylethanolamine-N-methyltransferase (PNMT)-positive neurons were observed.
分别运用间接免疫荧光技术和未标记抗体酶法（PAP 技术），在光镜和电镜水平对大鼠嗅球进行了研究。使用了针对儿茶酚胺合成过程中所有 4 种酶的抗体。在主嗅球中，前两种酶，即酪氨酸羟化酶（TH）和多巴脱羧酶（DDC），而非多巴胺-β-羟化酶（DBH），存在于一定比例的球周细胞体和树突中，这表明这些神经元合成多巴胺（DA）。因此，这种胺可能作为一种递质在球周细胞与僧帽细胞形成的一些球内树突 - 树突突触处释放。有证据表明一些球周细胞以γ-氨基丁酸（GABA）作为其递质。这样，一个在形态和生理上均一的神经元群体可以根据递质组织化学标准进行细分。在肾小球中，有印象认为 DDC 阳性纤维比 TH 阳性纤维更多。这种大概是 DDC 阳性但 TH 阴性的突起可能代表 5 - 羟色胺（5 - HT）神经末梢。在颗粒层、外丛状层以及极少情况下在肾小球层可见 DBH 阳性纤维，可能代表从脑干下部上行的去甲肾上腺素（NA）神经末梢。弱荧光的 DDC 阳性纤维可能代表上行 5 - HT 神经元的神经末梢。未观察到苯乙醇胺 - N - 甲基转移酶（PNMT）阳性神经元。
