Gerbils Research Articles

THE DIET OF VARANUS GRISEUS IN THE SOUTHERN COASTAL PLAIN OF ISRAEL (REPTILIA: SAURIA)

ABSTRACT Fecal pellets were collected and analyzed microscopically during a two-year study of the desert monitor (Varanus griseus) in a sand-dune area south of Holon. V. griseus was found to be a predator-scavenger carnivore type, eating almost any animal of appropriate size. Although 92.2% of the fecal pellets contained invertebrates (mainly arthropods), the higher frequency of occurrence of the smaller species among the invertebrates is probably due to secondary predation. The main prey items included rodents (mostly gerbils, Gerbillus sp., and jirds, Meriones sp.), bird eggs (presumably chukar partridge, Alectoris chukar eggs), birds (mainly partridge chicks), skinks (Chalcides sp.), fringe-toed lizards (Acanthodactylus sp.), chameleons (Chamaeleo chamaeleon), elegant geckos (Stenodactylus sthenodactylus), tortoises (Testudo graeca) and snakes (including the venomous Vipera xanthina palaestinae). Less frequent were: hedgehogs (Hemiechinus auritus), leverets (Lepus europaeus), Sanis pygmy shrew (Suncus ...

Is Light Therapy Underused

Light therapy is a proven therapy for seasonal depression, but the neurobiology has been unclear. To further understand how light affects serotonin pathways, investigators examined a subset of retinal ganglion cells that project to serotonin neurons in the dorsal raphe. Gerbils were housed in total darkness …

Radiation treatment of bone hydatid disease

Objective Explore the efficacy that radiation (6WV-X-ray) treat bone hydatid disease.Methods Establish seventy gerbils bone hydatid disease animal models which were randomly divided into four groups,one group was to be control group,the animal models in other three groups were given 40 Gy/5 times,50 Gy/5 times,60 Gy/5 times,6MV-X-ray positioning radiotherapy,3 months later(the end of radiotherapy),to observe the gerbils,general situation,to compare the mortality of scolex,protein and calcium concentration in capsule fluid,to observe the pathological changes of the horny layers and germinal layers,the varying of the bone cells in the irradiation areas and the ultrastructure of echinococcus granulosus cysts.Results Over the past 3 months,gerbils in each group has death cases,but the survival ones,general behaviors were normal.Among the groups,the difference of the mortality of scolex(such as Control group:22.6,40 Gy/5 times group:96.6,50 Gy/5 times group:131.5,60 Gy/5 times group:155.5) was statistically significant (P ＜ 0.01).Protein concentration (calcium ion concentration) in cyst fluid decrease (increase) with irradiation doses increase,The protein (calcium) concentrations are such as-the control group:1.0241 (2.8875),40 Gy/5 time group:0.7245 (3.0541),50 Gy/5 times group:0.6171 (3.5446) Gy to 60 Gy/5 times group:0.5058 (3.8241),which comgpared among each group there were significant differences(P ＜ 0.01).Histopathological results showed that echinococcus sac in the treatment groups showed different degrees of degeneration or necrosis,which compared with control group there were significant changing.Compared between 40 Gy and 50 Gy group,40 Gy and 60 Gy group,the pathological changes of echinoccus sac were significant difference (P ＜ 0.01),but between 50 Gy and 60 Gy group the pathological changes is not obvious (P ＞ 0.05).The bone cells of the irradiated groups have been varying degrees of degeneration or necrosis.By electron microscopy,with the irradiation doses increase,the horny layers and germinal layers have been varying degrees of damage.Conclusion Radiation therapy is effective for bone hydatid disease,but need to select the appropriate radiation dose according to the actual situation,to prevent the occurrence of irreversible osteonecrosis. Key words: Bone echinococcosis ; Model, animal; Radiotherapy

Effect of ischemic preconditioning on p38MAPK activation after cerebral ischemia-reperfusion in gerbil

Objective To study the effect of ischemic preconditioning on p38MAPK pathway after ischemia - reperfusion injury in gerbils. Method Gerbils were divided randomly into control group, ischemia - reperfusion group ( I/R ) , ischemia preconditioning group ( IP ) and inhibitor SB203580 group. Transient ischemia - reperfusion model and ischemia preconditioning model were performed. The expression levels of p38MAPK phosphorylation were detected by immunohistochemistry and Western blot, the neurons apoptosis were detected by TUNEL method and the infarction volume assessments were performed by TTC staining. Results Compared with control group, there were higher expression levels of p38MAPK phosphorylation,more apoptotic neurons in I/R group. The p38MAPK phosphorylation \positive cells and TUNEL positive cells were located in the same neurons. Compared with I/R group, there were lower expression levels of p38MAPK phosphorylation,fewer apoptotic neurons and smaller infarction volumes in IP group( P 0. 05 ) . However, the number of apoptotic neurons and infarction volumes were obviously changed ( P <0.05). Conclusions IP has protective effect from I/R damage in gerbils, which might be not only involved p38MAPK pathway. Key words: Reperfusion injury; Ischemic preconditioning; Mitogen - activated protein kinases; Apoptosis

Influence of the Occlusal Alteration in the Mandible Morphology of the Gerbil

Considerando los aspectos biomecanicos, muchos hechos deben ser entendidos sobre la mandibula, haciendo necesario comprender cuales son los efectos que pueden causar una alteracion oclusal unilateral en el sistema estomatognatico. El objetivo de este estudio fue analizar la maloclusion por la extraccion de los dientes unilaterales sobre la morfologia de la mandibula en el gerbo. Se utilizaron 10 gerbos Meriones unguiculatus, machos jovenes, con un peso aproximado de 50-60g, divididos en dos grupos (n = 5), un grupo experimental y otro control, en los cuales se evaluaron las dos hemimandibulas, totalizando 20 muestras que fueron medidas con un caliper digital. Las medidas tomadas fueron: (1) longitud y (2) ancho del condilo mandibular, y (3) la altura del cuerpo en la region de los primeros molares mandibulares. Los datos de estas mediciones se analizaron mediante la prueba ANOVA y Mann-Whitney. Los resultados de este estudio mostraron una diferencia estadisticamente significativa en las tres medidas entre los grupos experimental y control. El ancho de la cabeza de la mandibula (condilo) mostro una diferencia estadistica entre los lados ipsilaterales y contralaterales a la extraccion dentaria. Se concluyo que existe una alteracion unilateral de la masticacion inducida por la extraccion de dientes unilateralmente, causando un desequilibrio y promoviendo no solo una modificacion en el patron de crecimiento craneofacial, sino tambien un efecto nocivo obre el sistema estomatognatico del gerbo utilizado como modelo experimental en este estudio.

Comparison of ultrastructure and lectin histochemistry on the anterior medial gland of nasal septum in rat and gerbil.

The anterior medial gland (AMG), located in the submucosa of rodent nasal septum, is suggested to provide fluid for humidification of inspired air. Tremendous variation of the environmental air humidity, on which rats and gerbils depend to live, leads us to expect a multiplicity on ultrastructure and various subcellular glycoconjugate distribution within the AMG acinar cells between these two species. Electron microscopy revealed that: (1) The nucleus of AMG acinar cells in rat was irregular-shaped, but that in gerbil was round or elliptical; (2) Secretory granules in rat AMG acinar cells contained homogenous content with various electron density. However, two types of secretory granules in gerbil AMG acinar cells were found: one with lamellated-structure and high electron density, while the others had particulate materials; (3) Myoepithelial cells were present in the acinus of medial and posterior regions in rat AMG, but absent in gerbil; and (4) Nerve terminals were present only in the medial and posterior rat AMG, but in all three regions of the gerbil AMG. Lectin histochemistry demonstrated that: (1) Rat and gerbil AMG acinar cells expressed strong affinity toward Con A and WGA, but neither showed any reactivity toward UEA and PNA; and (2) Varying degrees of reactivity toward different lectins, including DBA, PNA, SBA and EBL, were recognized in rat and gerbil AMG acinar cells. We confirm the species variation on the ultrastructure and lectin histochemistry of AMG in rats and gerbils, and speculate that these variations may be due to the different living environment.

Chemocommunication among domestic cats, mediated by the olfactory and vomeronasal senses. I. Chemocommunication.

Chemocommunication functions are known in many social mammals, such as gerbils, hamsters, and deer. But also mammals known as at least partly solitary do communicate by chemical signals. The existence and use of pheromones in domestic cats was the subject of this study. It turned out that male and female cats spent much time in exploring their own and foreigners' urine and skin gland secretion rubbed off on several objects. Male receivers performed sniffing and flehmen more frequently than females on the same urine, whereas female cats paid more attention to skin gland secretion. Both urine and cheek gland secretion of the female donor appeared to contain pheromones which inform the tomcat about her hormonal phase.

Chronic deferasirox administration decreases hepatic oxidative stress and apoptosis in the iron overloaded gerbil

Chronic deferasirox administration decreases hepatic oxidative stress and apoptosis in the iron overloaded gerbil

Molecular Phylogeny of the Subfamily Gerbillinae (Muridae, Rodentia) with Emphasis on Species Living in the Xinjiang-Uygur Autonomous Region of China and Based on the Mitochondrial Cytochromeband CytochromecOxidase Subunit II Genes

Rodents belonging to the subfamily Gerbillinae and living in the Xinjiang-Uygur autonomous region of China were collected in field surveys between 2001 and 2003. We found four Meriones species, including M. chengi M. liycus, M. meridianus, and M. tamariscinus, as well as related species from different genera, Rhombomys opimus and Brachiones przewaliskii For phylogenetic analyses of these gerbilline species, DNA sequences of parts of the mitochondrial cytochrome b (Cytb) and cytochrome c oxidase subunit II (COII) genes were examined with the neighbor Joining, maximum parsimony, maximum likelihood, and Bayesian inference methods. Our phylogenetic analyses suggest that the genus Meriones is not monophyletic and place M. tamaricinus as the sister taxon to a clade comprising Brachiones, Psammomys, Rhombomys, and the other Meriones species. The remaining Meriones species separate into three lineages: M. meridianus (including M. chengi), Meriones unguiculatus, and a clade that includes multiple Meriones species originating from Asia, the Middle East, and Africa. The phylogenetic relationships among the genera Brachines, Meriones, Psammomys, and Rhombomys remain ambiguous, probably due to the saturation of mutations that occurs in fast-evolving mitochondrial DNA. In addition, intraspecific variation was observed for M. meridianus, and this mostly correlated with collection localities, i.e., the northern and southern parts of the Xinjiang region. This variation corresponded to interspecific levels of divergence among other lineages of Meriones. Interestingly, no differences were observed in either the Cytb or COII gene sequences isolated from M. chengi collected from the Turfan Basin in the north and those from M. meridianus in the south, suggesting that M. chengi may be a synonym of M. meridianus.

Prestin forms tetramer with each subunit being mechanically independent

Prestin is the motor protein of cochlear outer hair cells (OHCs). It is able to perform rapid and reciprocal electromechanical conversion that underlies OHC electromotility. Due to the inadequate size of a single prestin molecule to form the ~12nm intramembraneous protein particles (IMPs) in the OHC lateral membrane (LM), the possibility of prestin oligomerization has been proposed. It has been suggested that prestin molecules form high–order oligomers, most likely as the tetramer, in heterologous systems. In OHCs, however, the oligomeric structure of prestin remains unclear. Here we calculated the prestin–related charge density in both gerbil and guinea pig OHCs through measuring their nonlinear capacitance (NLC) and LM surface area, showing that the average charge density (22, 608 μM–2in gerbils; 19, 460 μM–2in guinea pigs) is statistically 4 times the average density of IMPs (5, 686 μM–2in ger–bils; 5, 000 μM–2in guinea pigs). This suggests that each IMP contains four prestin molecules based upon the notion that each prestin transfers a single elementary charge, implying that prestin forms tetramers in OHCs. To determine whether the prestin tetramer functions as a mechanical unit, we subsequently compared the slope factors (α) of electromotility and NLC simultaneously measured from the same OHC, showing that the a values of the two are statistically the same. This suggests that each prestin molecule in the tetramer is mechanically independent and equally contributes to OHC electromotility.

I'm not going outside until I check on my gerbil

I'm not going outside until I check on my gerbil

Effects of BDNF pretreatment against cerebral ischemia-reperfusion injury in gerbils

Objective To investigate the effects of brain-derived neurotrophic factor (BDNF) pretreatment on neuron apoptosis and the expression of Bcl-2 and Bax protein following global cerebral ischemia-reperfusion (I/R) injury in gerbils. Method Forty-eight mongolian gerbils were randomly divided into six groups in equal number (n = 8): normal control group (group C), ischemia-reperfusion group (group I/R) and four BDNF pretreatment groups according to various lengths of time from BDNF pretreatment to ischemia-reperfusion. The BDNF pretreat-ment was carried out in gerbils with lateral ventricular injection of BDNF 0.5μg 6 h, 12 h,24 h and 48 hours be-fore cerebral ischemia, and those gerbils assigned into PR6, PR12, PR24 and PR48 groups. The global cerebral is-chemia-reperfusion was induced by occlusion of bilateral common carotid arteries for 20 minutes and then the arter-ies were released for 24 hours reperfusion. The confirmation of global cerebra ischemia was evidenced by the ap-pearance of mydriasis and disappearance of light reflex and righting reflex. Twenty-four hours later, all gerbils including those of control group were sacrificed and a piece of tissue was taken from frontal cortex just behind the optic chiasma 1～4 millimeter for making paraffin sections. Neuron apoptosis was identified by using TUNEL and immunohischemistry was used to detect the expression of Bcl-2 and Bax protein in cerebral cortex. The data were analyzed by using analysis of variance. Results There were no apoptotic cells, and expression of Bcl-2 and Bax protein positive cells found in group C. Neuron apoptosis in brain cortex was detected in I/R group and BDNF pre-treatment groups. The indexes of neuron apoptosis in BDNF pretreatment groups were markedly lower than those in group I/R (P < 0.01). Compared with group I/R, the index of expression of Bcl-2 protein positive cells was in-creased significantly in BDNF pretreatment groups (P = 0.005), while the index of expression of Bax protein posi-tive cells were decreased significantly (P < 0.01 in all groups). Among 4 BDNF pretreatment group, the lowest apoptosis index and lowest of expression of Bax protein positive cells were found in PR6 and PR12 BDNF pretreat-ment groups (P = 0.0056 and 0.001, respectively). Conclusions Different time windows of BDNF pretreatment can decrease the neuron apoptosis in different degree, and protect brain against cerebral ischemia-reperfusion injury significantly. Among BDNF pretreatment time windows, pretreatment of 6 hours and 12 hours are the better ones.The mechanism of protection of BDNF pretreatment may be attributed to inducing Bcl-2 protein expressions and in-hibiting Bax protein expressions, and thereby inhibiting neuron apoptosis. Key words: Brain ischemia; Reperfusion; Brain-derived neurotrophic factor; Apoptosis; Apoptotic related-genes

Expression of smad2/3 protein and the effects of flunarizine on its expression in brain tissue following transient cerebral ischemic reperfusion in gerbils

Objective To study the expression of smad2/3 protein and the effects of flunarizine on the its expression in braln tissue following transient cerebral ischemie reperfusion in gerbils. Methods A cerebral ischemia-reperfusion model in gerbils was established by clamping both common carotids. Thirty-five gerbils were randomly divided into three groups, sham operation group, cerebral ischemia-reperfusion group and flunarizine treatment group. The expression of smad2/3 protein in brain tissue was detected by immunohistochemistry technique. Results Experimental results revealed that smad2/3 protein was expressed in neuroeyte in 35 gerbil brain. Compared with sham operation group, the expression of smad2/3 protein in neurecytes of cerebral isehemia-reperfusion group was evidently increased at the lst day, 3rd day and 7th day (P <0. 01). Compared with cerebral ischemia-reperfusion group, the expression of smad2/3 protein in neurecytes of gerbils in flunarizine treatment group was evidently decreased at these time point (P < 0.05). Condusions Smad2/3 protein was expressed in nettrcvytes of gerbils. Expression of smad2/3 protein in neuroeytes of gerbils was evidently increased following cerebral ischemic reperfusion, and its expression in flunarizine treatment group was evidently decreased. Key words: DNA-binding proteins/ME; Brain isehemia/ME/DT; Reporfusion injury/PC; Flunarizine/PD[2] Wang Y, Chong CF, Morales M, et al. Protective effects of glial cell line-derived neurotrophic factor in ischemic brain injury Ann N Y Acad Sci, 2002,962:423-437.

The effect of nitric oxide on expression of isoflurane preconditioning against brain ischemia-reperfusion

Objective To investigate the effect of isoflurane preconditioning on Bcl-2 and Bax mRNA expression and the signaling pathway of nitric oxide against brain ischemia-reperfusion(I/R).Methods Seventy-five male gerbils were randomly divided into 5 groups(n=15):SHAM,I/R,ISO,AG+ISO and AG group.Global cerebral I/R was produced by occlusion of bilateral common carotid arteries for 5 minutes and confirmed by isoelectric potential on EEG.In ISO group,the animals inhaled 1.2%-1.5% isoflurane for 30 minutes followed by 30 minutes wash-out period before I/R.In AG+ISO group,30 minutes after aminoguanidine,200 mg/kg i.p.isoflurane was inhaled as ISO group,and aminoguanidine was injected 30 min before I/R in AG group.After 24 hours,the forebrains were collected,and the expression of Bcl-2 and Bax mRNA was determined by reverse transcriptase polymerase chain reaction.Results Bcl-2 mRNA expression in ISO group(1.22±0.12) was significantly higher than that in sham(0.83±0.16),I/R(0.83±0.11) and AG+ISO group(0.82±0.12)(P<0.05).Bax mRNA expression in I/R and AG group was significantly higher than that in sham group(P<0.05),and the expression in ISO group was higher than that in AG+ISO group.Conclusion Nitric oxide is involved in the signaling pathway of isoflurane preconditioning and has the protection effect on gerbil brain against I/R. Key words: Nitric oxide; Isoflurane/PD; Reperfusion injury; Brain ischemia; Gene expression

The changes of HSP27 in brain tissue and its antibody in serum following cerebral ischemic reperfusion in gerbils

Objective To study the expressions of heat shock protein 27(HSP27)in brain tissue and the changes of antibody of HSP27 in serum after transient cerebral ischemic reperfusion in gerbils.Methods A cerebral ischemia-reperfusion model in gerbils was established by clamping both common carotids.Sixty gerbils were randomly divided into normal control group,sham operation group and ischemia-reperfusion(IR)group.The expressions of HSP27 in brain tissue were detected by immunohistochemistry technique and the changes of antibody of HSP27 were detected by ELISA technique at the 6th hour,1st day,3rd and 7th day after IR.Experimental results were analyzed with the statistic soft package of Spss11.5.Results Experimental results revealed that HSP27 were expressed in neurons and gliacytes of the brain tissue in the 60 gerbils.There was mild expressions of HSP27 in neurons and gliacytes in normal control group and sham operation group, but it has no significant difference between the two groups(P＞0.05).Compared with normal control group,the expressions of HSP27 in neurong and gliacytes of ischemia-reperfusion gerbils were evidently increased at the 6th hour,1st day,3rd day and 7th day,especially at the 3rd day(P＜0.01).Conclusions Expressions of HSP27 in neurons and gliacytes of gerbils were increased markedly.This suggested that the increased expressions of HSP27 could protect the brain tissue from damage.The changes of antibody in serum of normal control group,sham operation group were evidently less than that in group IR,which suggest the HSP27 antibody may damage our body. Key words: Brain ischemia; Reperfusion; Heat-shock proteins

Interaural time difference processing in the mammalian medial superior olive

The dominant cue for localization of low-frequency sounds are microsecond differences in the time-of-arrival of sounds at the two ears [interaural time difference (ITD)]. In mammals, ITD sensitivity is established in the medial superior olive (MSO) by coincidence detection of excitatory inputs from both ears. Hence the relative delay of the binaural inputs is crucial for adjusting ITD sensitivity in MSO cells. How these delays are constructed is, however, still unknown. Specifically, the question of whether inhibitory inputs are involved in timing the net excitation in MSO cells, and if so how, is controversial. These inhibitory inputs derive from the nuclei of the trapezoid body, which have physiological and structural specializations for high-fidelity temporal transmission, raising the possibility that well timed inhibition is involved in tuning ITD sensitivity. Here, we present physiological and pharmacological data from in vivo extracellular MSO recordings in anesthetized gerbils. Reversible blockade of synaptic inhibition by iontophoretic application of the glycine antagonist strychnine increased firing rates and significantly shifted ITD sensitivity of MSO neurons. This indicates that glycinergic inhibition plays a major role in tuning the delays of binaural excitation. We also tonically applied glycine, which lowered firing rates but also shifted ITD sensitivity in a way analogous to strychnine. Hence tonic glycine application experimentally decoupled the effect of inhibition from the timing of its inputs. We conclude that, for proper ITD processing, not only is inhibition necessary, but it must also be precisely timed.

Gerbils can distinguish 'me' from 'you'

Gerbils can distinguish 'me' from 'you'

Snake DNA found inside a gerbil

Snake DNA found inside a gerbil

Punishment Suppression: Some Effects on Alternative Behaviour:

Three experiments using a multiple response technique (Dunham, 1978) with Mongolian gerbils were designed to investigage die effect of different methods of producing response suppression on nonsupp...

New Records of Naked-footed Gerbil Gerbillus nanus and Pygmy Gerbil Gerbillus cfr. henleyi (Rodentia, Muridae) from Iran

Gerbillus nanus is a highly polytypic species exhibiting considerable geographical variation, both in external and cranial characters. In the present study, specimens were collected from different localities in the northeastern, eastern, central and southern Iran. The values for external end cranial measurements have been given. The specimens present the existence of two different morphotypes of Baluchistan gerbil – short-tailed and longtailed – existing sympatrically, especially in the southern parts of Iran. Moreover, in this study, one specimen was captured from Abarkouh desert and identified as Gerbillus cfr. henleyi which is the first report of the presence of this species in Iran. This new record expands the distribution of G. henleyi because it is the most eastern record of this species..