Belay Hiwote T, Brown Ian R
Center for the Neurobiology of Stress, University of Toronto at Scarborough, Toronto, Ontario, Canada.
J Neurochem. 2006 Apr;97 Suppl 1:116-9. doi: 10.1111/j.1471-4159.2005.03591.x.
Stressful stimuli induce two distinct cellular reactions, the heat-shock (stress) response and programmed cell death. This study utilizes a dual procedure involving immunocytochemistry for heat-shock protein localization and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay for localization of cell death at the cellular level. Whole-body hyperthermia resulted in cell death in the adult rat thymus and testis with a robust signal seen in the testis. Distinct populations of constitutively expressed Hsc70-positive cells and TUNEL-positive cells were apparent. Cellular layers that exhibited high levels of Hsc70 were not triggered into cell death by the thermal stress. High expression of Hsc70 was observed in neuronal populations in the dentate gyrus, CA1 and CA2 region of the hippocampus and Purkinje neurons of the cerebellum. Hyperthermia-induced cell death was not observed in these neuronal cell types, suggesting that neuronal expression of constitutive Hsc70 may play roles in preprotecting neurons from stressful stimuli.
应激刺激会引发两种不同的细胞反应，即热休克（应激）反应和程序性细胞死亡。本研究采用了一种双重程序，包括用于热休克蛋白定位的免疫细胞化学方法以及用于在细胞水平定位细胞死亡的末端脱氧核苷酸转移酶介导的脱氧尿苷三磷酸缺口末端标记（TUNEL）测定法。全身热疗导致成年大鼠胸腺和睾丸中的细胞死亡，在睾丸中可见强烈信号。组成性表达的Hsc70阳性细胞和TUNEL阳性细胞的不同群体很明显。表现出高水平Hsc70的细胞层并未因热应激而引发细胞死亡。在海马齿状回、CA1和CA2区域的神经元群体以及小脑的浦肯野神经元中观察到Hsc70的高表达。在这些神经元细胞类型中未观察到热疗诱导的细胞死亡，这表明组成性Hsc70的神经元表达可能在预先保护神经元免受应激刺激方面发挥作用。
