牛磺酸对照射后大鼠海马齿状回区神经元再生的影响

目的观察牛磺酸对全脑照射后大鼠海马齿状回区神经元再生的影响。方法成年雄性Wistar大鼠，用6MV高能X线行全脑照射，吸收剂量为10Gy，用TUNEL法检测海马齿状回区凋亡细胞，用5-溴脱氧尿苷（BrdU）标记法检测再生神经细胞数量，用BrdU与NeuN双染法标记再生神经元，计数再生神经元占新生细胞数量的比例。结果颅脑照射后12h，大鼠海马齿状回区TUNEL阳性细胞数量较对照组明显增加，用牛磺酸处理可降低照射后TUNEL阳性细胞数量（P〈0．05），牛磺酸对照射后BrdU阳性细胞数无明显影响，而可增加照射后新生细胞向神经元分化的比例（P〈0．01）。结论牛磺酸可抑制照射后大鼠海马齿状回区增殖细胞凋亡，促进神经元再生，可能与其保护神经元再生微环境的作用有关。

Effect of taurine on neurogenesis in the dentate gyrus of adult rat hippocampus after whole brain irradiation

Objective: To observe the effect of taurine on neurogenesis in the dentate gyrus of adult rat hippocampus after whole brain irradiation.Methods: Adult male Wistar rats were subjected to 10Gy whole brain irradiation,apoptotic cells were quantified by TUNEL staining,proliferating cells were detected by Brdu labeling,the proportion of proliferating(BrdU~+) cells that co-express markers for mature neurons(NeuN) were determined by double immunostaining.Result: Twelve hours after irradiation,the number of TUNEL positive cells increased markedly in the dentate gyrus of adult rat,which could decreased by taurine administration(P<0.05).In irradiated rats,taurine didn't alter BrdU positive cells reduction,but the proportion of BrdU positive cells that coexpress markers for mature neurons(NeuN) was elevated after taurine administration(P<0.01).Conclusions: Taurine can inhibit apoptosis immediately after irradiation.It can also promote neurogenesis two months after irradiation,which may be related to its beneficial effects in protecting neurogenic niche.