Objective To assess the health status of rodent laboratory animals by pathological diagnosis, our lab has being take apart in investigating the quality of laboratory animals in Beijing area for years and offer some advices for standardized breeding to ensure accurate results of scientific research.This paper focuses on the analysis of laboratory rodent samples that collected in October 2014.Methods We collected the heart, liver, spleen, lung, kidney, large intestine and small intestine, and put these organs into 10%Calcium formaldehyde solution for fixation, and then prepared into two different sections for optical microscopy observation including all paraffin specimens stained with H&E and the frozen sections stained with Oil Red-O and PAS.Results The vast majority of laboratory rodents were up to standard, but there still a problem in individual units.The main problem is liver and lung disease.The rate of Hepatocyte swellingis 6%(mouse), 2.5% (rat), 8.2% (guinea pig), moreover part of them were lipidosis, according to Oil Red-O stain.the mainly problem of lung is congestion ,edema and Interstitial pneumonia ,the detectable rate of pulmonarydiseases is 15.5%(guinea pig).Conclusions The vast majority of laboratory rodents were pathologically diagnosed as healthy animals.The liver disease may be caused by improper feeding.And disease of lung may led by haze, unqualified bedding and low temperature.

Objective To investigate the role of TLR4/NF-κB signal pathway in pathogenesis of brain inju-ry during deep hypothermia circulatory arrest(DHCA). Methods BV2 microglia cells were subjected to oxygen-glucose deprivation/reoxygenation(OGD/R),in vitro model for DHCA. The BV2 were randomly divided into the control group(C group)and the experimental group(O group). BV2 viability was determined by CCK-8 assay. TLR4 and its downstream signaling molecules ,MyD88 and phosphorylated NF-κB (p-p65) expressions were detected by Western blotting. TLR4 mRNA expression in BV2 microglial cells were determined by RT-PCR. Level of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in culture medium was detected by ELASA. Results Compared with the group C,BV2 microglia cell viability in experiment group was obviously weaker(P<0.05). Expressions of TLR4,MyD88 and phosphorylated NF-κB(p-p65)from the experiment group increased remarkedly than those from the group C (P < 0.05). TLR4 mRNA level was higher significantly in the group O than in the group C (P < 0.01). Production of IL-6 and TNF-α in the group O were up-regulated apparently compared to the group C(P<0.01). Conclusion TLR4/NF-κB signaling pathway contributed to activation of BV2 microglia cells treated by OGD/Reoxygenation ,which was probably the exactly way that involved in pathogenesis of brain injury during deep hypothermia circulatory arrest.