Malendowicz L K, Nussdorfer G G, Trejer M
Department of Histology and Embriology, School of Medicine, Poznan, Poland.
Life Sci. 1997;61(6):641-3. doi: 10.1016/s0024-3205(97)00439-6.
5-Bromo-2'-deoxyuridine (BrdU) has been recently found to enhance adrenal glucocorticoid secretion in rats. Since BrdU-labeling is today the most employed technique for assessing cell proliferation, we have investigated whether this side-effect of BrdU may influence mitotic activity (as evaluated by metaphase-arrested cell counting) in the thymus cortex and regenerating adrenal cortex. BrdU (1 mg/100 g body weight) evoked a 6-fold rise in the blood level of corticosterone in intact rats, but not in animals bearing regenerating adrenals, in which glucocorticoid secretion was very low. Mitotic index in the thymus of intact rats was not changed by BrdU, but it was strongly depressed in regenerating adrenals. These findings rule out the possibility that the glucocorticoid secretagogue action of BrdU exerts a sizable effect on the proliferative activity of both thymus and adrenal cortex. The marked lowering in the mitotic rate in the regenerating adrenal cortices could be ascribed to the well-know differentiation promoting action of BrdU, a finding which, if confirmed, would make highly unreliable the use of BrdU-labeling technique in cultures of adrenocortical cells.
最近发现5-溴-2'-脱氧尿苷（BrdU）可增强大鼠肾上腺糖皮质激素的分泌。由于如今BrdU标记是评估细胞增殖最常用的技术，我们研究了BrdU的这种副作用是否会影响胸腺皮质和再生肾上腺皮质中的有丝分裂活性（通过中期停滞细胞计数评估）。BrdU（1毫克/100克体重）使完整大鼠的皮质酮血水平升高了6倍，但对肾上腺正在再生的动物却没有这种作用，因为这些动物的糖皮质激素分泌非常低。完整大鼠胸腺中的有丝分裂指数未因BrdU而改变，但在再生肾上腺中却显著降低。这些发现排除了BrdU的糖皮质激素促分泌作用对胸腺和肾上腺皮质增殖活性产生显著影响的可能性。再生肾上腺皮质中有丝分裂率的显著降低可能归因于BrdU众所周知的促进分化作用，如果这一发现得到证实，那么在肾上腺皮质细胞培养中使用BrdU标记技术将极不可靠。
