摘要
目的研究甲状腺素(T4)对发育期大鼠大脑皮质、海马细胞程序化死亡(PCD)的影响。方法采用甲巯咪唑(MM)复制甲状腺功能减退(甲减)孕鼠模型,出生后仔鼠为先天甲减鼠,同时设正常对照组:应用原位末端标记(TUNEL)方法检测出生后7、14、21d仔鼠大脑皮质、海马PCD阳性细胞。结果 (1)MM组各日龄仔鼠血清FT3、FT4水平明显低于对照组。(2)正常大鼠生后早期大脑皮质、海马均存在细胞凋亡,以生后7d TUNEL阳性细胞数最多,此后逐渐减低。甲减使各脑区各时点凋亡细胞数均明显增加。结论正常大鼠发育期大脑皮质和海马即存在细胞凋亡,甲状腺激素对大脑皮质、海马细胞凋亡有影响,可能是甲减性脑功能障碍的机制之一。
Objective To study the effects of thyroid hormone on programmed cell death (PCD) in cortex and hippocampus of developing rats. Methods In the study, the experimental animals were divided into two groups. Thiamazole (MM) was used to replicate the model of maternal pregnant hypothyroidism, which gave birth of infant rats with innate hypothyroidism. The age-matched normal neonatal rats were as controls. TOT-mediated dUTP nick end labeling (TUNEL) was carried out to detect the positive cells of PCD in cortex and hippocampus of postnatal 7,14 and 21 days rats. Results (1) Serum FF3 and FF4 levels of neonatal rats in MM group were significantly lower than those in normal control group. (2) There was PCD in cortex and hippocampus of the normal developing rat. PCD was maximal on the 7th day postnatally. Hypothyroidism led to the increase of apoptotic 'cells in every group. Conclusions (1)There exists PCD in cortex and hippocampus of the normal developing rat. (2)PCD increases in cortex and hippocampus of hypothyroid rats. It indicates that brain dysfunction with hypothyroidism might be related to PCD.
出处
《中国地方病学杂志》
CAS
CSCD
北大核心
2006年第3期254-256,共3页
Chinese Jouranl of Endemiology