Verhofstad A A, Hökfelt T, Goldstein M, Steinbusch H W, Joosten H W
Cell Tissue Res. 1979 Aug 3;200(1):1-13. doi: 10.1007/BF00236882.
The cellular localization of the enzymes tyrosine hydroxylase (TH), aromatic amino-acid decarboxylase (or dopa decarboxylase, DDC), dopamine beta-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) in the adrenal medulla of adult rats and rat fetuses (14th, 17th, 18th, 19th and 21st day) was examined. In the prenatal stages the medullary blastema and an adjacent part of the primitive sympathetic trunk were also investigated. Tissues were fixed in ice-cold 4% paraformaldehyde in 0.1 M phosphate buffer (pH 7.2). Cryostat sections (10 micron in thickness) were stained by the indirect immunofluorescence technique. Rabbit antibodies to TH (isolated from human pheochromocytoma), DDC, DBH and PNMT (the latter three isolated from bovine adrenal medulla) were used. Sections incubated with serum of non-immunized rabbits were used as controls. In the adult adrenal medulla, two cell types can be distinguished. One cell type contains only TH, DDC and DBH. The other cell type contains PNMT in addition. It is concluded that these cells correspond to the noradrenaline-(NA-) and adrenaline- (A-)storing cells respectively. In all prenatal stages TH, DDC and DBH are found in the primitive sympathetic trunk, in the medullary blastema, and in the medullary cells which have migrated into the cortical "anlage". PNMT is observed for the first time on the 18th day. Moreover, PNMT could only be demonstrated inside the adrenal gland. From these observations it is concluded that the capacity to synthesize NA is developed even before the "medullary" cells have reached the cortical "anlage". On the contrary, the capacity to synthesize A seems to be acquired only after this contact is established. The hypothesis is put forward that this phenomenon might indicate the induction of PNMT by glucocorticoids secreted by the fetal cortex.
研究了成年大鼠和大鼠胎儿（第14、17、18、19和21天）肾上腺髓质中酪氨酸羟化酶（TH）、芳香族氨基酸脱羧酶（或多巴脱羧酶，DDC）、多巴胺β-羟化酶（DBH）和苯乙醇胺N-甲基转移酶（PNMT）的细胞定位。在产前阶段，还研究了髓质胚基和原始交感干的相邻部分。组织用冰冷的0.1M磷酸盐缓冲液（pH 7.2）中的4%多聚甲醛固定。用间接免疫荧光技术对低温恒温器切片（厚度为10微米）进行染色。使用了针对TH（从人嗜铬细胞瘤中分离）、DDC、DBH和PNMT（后三种从牛肾上腺髓质中分离）的兔抗体。用未免疫兔的血清孵育的切片用作对照。在成年肾上腺髓质中，可以区分出两种细胞类型。一种细胞类型仅含有TH、DDC和DBH。另一种细胞类型还含有PNMT。得出的结论是，这些细胞分别对应于去甲肾上腺素（NA）储存细胞和肾上腺素（A）储存细胞。在所有产前阶段，TH、DDC和DBH存在于原始交感干、髓质胚基以及迁移到皮质“原基”的髓质细胞中。PNMT在第18天首次被观察到。此外，PNMT仅在肾上腺内部被证实。从这些观察结果得出的结论是，合成NA的能力甚至在“髓质”细胞到达皮质“原基”之前就已发育。相反，合成A的能力似乎仅在建立这种接触后才获得。提出的假说是，这种现象可能表明胎儿皮质分泌的糖皮质激素对PNMT的诱导作用。
