Objective To observe the changes in estrous cycle and vaginal smears in ovarectomized NOD/SCID mice.Methods To continuously observe the estrous cycle time by vaginal smears of NOD/SCID mice in consecutive nine days, twice daily.After ovariectomy, the changes of estrous cycle were observed by vaginal smears for 7 days.Results The estrous cycle in NOD/SCID mice was 4-6 days.Regular estrous mice accounted for 80%.There was no significant correlation between vaginal opening and estrous cycle status.After ovariectomy, the vaginal smears showed characteristics of metestrus or diestrus.Conclusions Vaginal smear cytology can be used to determine the estrous cycle and characteris-tics of NOD/SCID female mice.The ovariectomized operation of NOD/SCID female mice is effective.

Objective To explore the feasibility of mechanical chest compression to establish a rat model of car?diopulmonary resuscitation ( CPR) . Methods 4?month old healthy male Sprague Dawley rats were randomly divided into control group ( n=6 ) and model group ( n=10 ) . After induction of anaesthesia with 10% chloraldurate ( 3 ml/kg, i. p. ) , tracheal intubation and left femoral artery cannulation were performed. Under electrocardiographic and artery blood pressure monitoring, tracheal obstruction ( TO) was performed to rats in model group. At 2 min after the cardiac arrest ( CA) occurred, CPRs were administered to the rats using a self?made animal chest compressor, which provided chest?com?pression at a rate of 200 bpm. Results Shortly after TO, rats in the model group had respiratory arrest, cyanosis and ar?rhythmia. Electrocardiography indicated that CA occurred within 4-5 min, with a decreased artery systolic blood pressure ( <40 mmHg) and a zero pulse pressure. Return of spontaneous circulation ( ROSC) after the CPR was successfully a?chieved in 8 rats (80%), with a transient reperfusion arrhythmia. Finally, 60% of the rats (n=6) recovered to con?sciousness and survived for 24 hrs. The serum biochemical analysis indicated that there were electrolyte disturbances, aci?dosis, impaired renal functions and increased myocardial enzyme spectrum. Pathological examination revealed cardiac rhab? domyolysis, no?reflow phenomenon in renal glomeruli, decrease of neurons and pulmonary congestion in the model group rats. Conclusions Mechanical chest compression can provide minimal cardiac output for the requirement of CPR incardiac arrestin rats. It is feasible to establish rat CPR model with the mechanical chest compression.

Objective The aim of this study was to explore the effect of androgen deficiency on serum hormone levels, visceral fat accumulation and inflammatory gene expression in miniature pigs fed a high-fat diet ( HFD) . Methods Sexually mature male Chinese Wuzhishan miniature pigs were divided into three groups ( animals/group) as follows:intact male pigs ( SHAM) , castrated male pigs ( CAS) and castrated male pigs plus testosterone treatment ( CAS+T) . The pigs were fed a HFD diet for 12 weeks. Serum levels of testosterone and leptin were measured and visceral fat were dissected and weighted. qRT?PCR was performed to determine the mRNA expression levels of lipogenic, lipolysis and inflammation relat?ed genes. Results (1) Serum testosterone levels were significantly decreased but serum leptin levels were significantly in?creased in the castrated pigs. These effects were recovered after testosterone treatment. ( 2 ) Visceral fat percentage was significantly increased in the castrated pigs, and testosterone treatment reduced the increased visceral fat in the castrated pigs. (3) Castration and testosterone treatment had no significant effects on the expression levels of lipogenic genes (FAS and ACC) and lipolysis genes (HSL and ATGL) in pigs fed a HFD. (5) Castration significantly induced the expressions of inflammatory genes including Leptin, CD68, CCL16, CCL23 and SAA, and testosterone treatment recovered the expres?sions of the above genes in the castrated pigs. Conclusions Castration?induced testosterone deficiency promotes visceral fat accumulation and upregulates the expression levels of inflammatory genes in miniature pigs fed a HFD. Moreover, tes?tosterone treatment ameliorates castration?induced visceral fat accumulation and inflammatory response in HFD?fed pigs.

Objectives To systematically evaluate the effect of music given to pregnant rats on the development of brain functions in the offspring rats and to provide scientific evidence for the application of antenatal musical training and the promotion of welfare for laboratory animals.Methods We comprehensively retrieved and collected the research literatures related to the effect of music on brain function development in offsprings of the pregnant rats from Pubmed,Web of Science,Cochrane Library,Wanfang,Weipu,CNKI and CBMdisc.The retrieval time was set from the foundation date of databases to 2 April,2016.We selected literatures according to the inclusion and exclusion criteria,evaluated their utilities,then extracted and qualitatively described the data.Results Seven experimental studies were selected in this study including 4 published in Chinese and 3 in English.The object laboratory animals of those studies were Wistar or SD rats.Music materials involved comfort music,classic music,violin concerto(Liangzhu/The butterfly lovers).Intervention were given to the pregnant rats roundly from the gestation until parturition.These results showed that,to some extent,music stimulations during gestation may promote the development of brain function and improve spatial memory of the offspring rats.However,expressions of some functional receptors were not significantly altered.Conclusions Appropriate music provided to the pregnant rats promote the development of brain functions in their offspring.

Objective To investigate the effect of testosterone on mitotic orientation in rat prostate epithelial cells and the relative differential gene expression.Methods Twenty SPF male SD rats were divided into 2 groups at random and then subjected to castration.One group of rats was administrated with testosterone 3.7 mg daily for 30 days and the control group was only injected with olive oil.Microscopic analysis was performed using immunohistochemistry.Differential gene expression analysis was conducted by gene microarray and RT-PCR techniques.Results In the testosterone-adminis-trated group, there was a significant mitosis orientation parallel to the basement membrane.But in the control group, mito-sis orientation was oriented perpendicular to the basement membrane.Using the gene microarray and RT-PCR techniques, the cell proliferation genes such as Ran, Tgm4 and Wnt2 in Wnt signal pathway were up-regulated in the testosterone group.Conversely, suppressor cell proliferation genes such as Dkk3 and Fas were down-regulated.Conclusions Mitotic orientation of prostate epithelia cells is changed after testosterone administration.Wnt signal pathway and AR singling path-way also have an influence on the mitosis orientation and cell proliferation.

Object This experiment was conducted to study the relationship between CFTR gene expression in the intestinal tissues and secretory diarrhea.Methods Twenty-four Kunming mice were selected, half male and half female, and were randomly divided into 3 groups ( n=8 in each group):control group with intraperitoneal injection of 0.2 mL nor-mal saline, and the experimental group of mice by intraperitoneal injection of lipopolysaccharide(LPS) (6 mg/kg· bw). The mental state and intestinal morphology of the mice at 1 h and 8 h after LPS injection were observed to assess whether the secretory diarrhea model was successfully established.The expression of CFTR gene segments of intestine tissue was de-tected by fluorescence quantitative PCR.Results LPS induced secretory diarrhea.CFTR gene was expressed in the mouse duodenum, jejunum, ileum and colon tissues with different expression abundance.It was highest in the colon, but the difference was not significant between intestinal segments.Compared with the control group, LPS up-regulated the tran-scription level of CFTR gene in the duodenum, jejunum and ileum, and down-regulated the transcription of CFTR gene in the colon.Conclusions The results of our study suggest that the changes of the transcriptional level of CFTR gene are closely related with the diarrhea induced by LPS and the effects in different intestinal segments on the diarrhea is different. The jejunum plays a crucial role and the colon plays a least role in the Cl-secretion.

Objective To establish a reproducible rat model of acute rectal mucosal injury induced by acetic acid. Methods Fifteen healthy Sprague-Dawley rats were randomly divided into the control group (3 rats) and experimental group (12 rats).Acute rectal mucosal injury was induced by 4%acetic acid using a cotton swab inserted into the rat rec-tum for 1 min to a depth of 3 cm.The morphological characteristics were analyzed by the naked eye and histology at 0.5 h and 1, 4, and 6 days after acetic acid intervention.Results All rats survived 6-day study period.The successful rate of model establishment was 100%.From 0.5 h to 1st day after acetic acid intervention, the gross morphology of recta showed congestion, edema and ulcer to ulcer complicated with hemorrhage.The histology showed necrosis and hemorrhage of the epithelial tissue of the mucosa to complete and extensive necrosis of the mucosa.The glandular structure showed partial to complete loss.The submucosa showed edema to edema complicated with hemorrhage and congestion.The interstitial tissues showed vasodilatation and congestion to inflammatory cell invasion.From 4 to 6 days after acetic acid intervention, the rectal mucosal changes were obviously improved.Epithelial and glandular regeneration and inflammatory granulation occurred, but not fully recovered, some edema and redness, partial lack of glands were still present.Conclusions 4%acetic acid for 1 min can be used to successfully induce rat model of acute rectal mucosal injury.This procedure is easy to operate, with a high success rate,reproducible, and the alterations are lasting more than 6 days.This animal model is very suitable for rapid screening of topical drugs for the treatment for rectal mucosal injury.

Objective The purpose of this study was to establish a rapid method for synthesis and detection of guild RNA (gRNA) which is an essential component in CRISPR/Cas9 knockout technology .Methods First, the Nkp46 gRNA core fragment was synthesized as amplification template .Second , the forward and reversed primers of the matched gRNA were designed using the Nkp46 gene as reference sequence .Third, the DNA fragment of Nkp46 gRNA was amplified by PCR technology using the synthesized gRNA core fragment as template .The gRNA was reversely transcribed in vitro u-sing amplified DNA fragment as template .The efficiency and specificity of gRNA and its interaction with Cas 9 were detec-ted in vitro.Results The specificity and activity of Nkp46 gRNA were high .The obtained gRNA interacted with Cas 9 en-zyme and successfully cut the target double-stranded DNA at the designed site .Conclusions The method for synthesis and detection of gRNA established in this study is faster than the original method , and the created gRNA is fully functional .

Objective To study the effect of low frequency electrical stimulation on blood hormone levels in differ -ent animals.Methods At 12 h, 24 h and 36 h after low frequency electrical stimulation to Chinese tree shrews , Wistar rats, and BALB/c mice, respectively, the blood noradrenaline (NA) and endothelin (ET) levels were determined by ra-dioimmunoassay ( RIA) .Results The blood NA and ET levels of electrical stimulation group were significantly higher than that in the control group (P <0.01).At 24 h after reserpine treatment, the same electrical stimulation was given. The NA, ET levels were significantly decreased compared with that in the electrical stimulation group (P<0.05 to 0.01). Different animals responded to the same electric stimulus differently , following the order of Chinese tree shrews >Wistar rats >BALB/c mice.Conclusions Low frequency electrical stimulation can promote the release of noradrenaline and en -dothelin in Chinese tree shrews , Wistar rats and BALB/c mice.Reserpine can reduce the stress induced by low frequency electric stimulation to the body .

Mongolian gerbil is a multifunctional laboratory anima1 resource with Chinese characteristics.It has many advantages for some research fields, and play an important role.The more biological characteristics of Mongolian ger-bils discovered with in-depth research will promote diverse application of this resoure.In this paper, we reviewed the devel-opment of application of Mongolian gerbils in taxonomy, parasitology, microbiology, cerebral ischemia, lipid metabolism, neurological diseases, and cancer researches.