• BMB Reports
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• v.44 no.5
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• pp.306-311
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• 2011

Although NCX-3 is highly expressed in the brain, the distribution of NCX-3 in the epileptic hippocampus is still controversial. Therefore, to assess the distribution and pattern of NCX-3 expression in epileptic hippocampus, we performed a comparative analysis of NCX-3 immunoreactivities in the hippocampus of seizure-resistant (SR) and seizure-sensitive (SS) gerbils. In SR gerbils, NCX-3 immunoreactivity was higher than pre-seizure SS gerbils, particularly in the pavalbumin (PV)-positive interneurons. Three h post-ictal, NCX-3 immunoreactivity in the SS gerbil hippocampus was markedly elevated to the level of SR gerbils. Six h post-ictal, the expression of NCX-3 was reduced to the level of pre-seizure SS gerbils. Therefore, the results of the present study suggest that down-regulation of NCX-3 expression in the SS gerbil hippo-campus may be involved in the hyperexcitability of SS gerbils due to an imbalance of intracellular $Na^+/Ca^{2+}$ homeostasis and $Ca^{2+}$ concentration.

• Korean Journal of Veterinary Service
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• v.29 no.4
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• pp.469-482
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• 2006

The term 'heat shock protein (Hsps)' was derived from the fact that these proteins were initially discovered to be induced by hyperthermic conditions. In response to a range of stressful stimuli, including hyperthermia, immobilization, UV radiation, amino acid analogues, arsenite, various chemicals, and drugs the mammalian brain demonstrates a rapid and intense induction of the heat shock protein. Moreover, Hsps were expressed on the various pathological conditions including trauma, focal or global ischemia, hypoxia, infarction, infections, starvation, and anoxia. Especially, Hsp25 has a protective activity, facilitated by the ability of the protein to decrease the intracellular levels of reactive oxygen species (ROS) as well as its chaperone activity, which favors the degradation of oxidized proteins. Recently, it has clearly demonstrated that Hsp25 is constitutively expressed in the adult mouse cerebellum by parasagittal bands of purkinje cells in three distinct regions, the central zone (lobule VI-VII) and nodular zone (lobule IX-X), and paraflocculus. The Mongolian gerbil has been introduced into stroke study model because of its unique brain vasculature. There are no significant connections between the basilarvertebral system and the carotid system. This anatomy feature renders the mongolian gerbil susceptible to forebrain ischemia-induced seizure. The present study is designed to examine the pattern of Hsp25 expression in the cerebellum of this animal in comparison with that in mouse.

• The Journal of Korean Medicine
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• v.21 no.3
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• pp.88-98
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• 2000

Objectives : This study was carried out to evaluate the effect of Boyanghwano-tang Extracts on Reversible Forebrain Ischemia in Mongolian Gerbils. Methods : The water content of cerebral edema and the morphologicalㆍneurocytochemistrical change of neuron in MG were implemented to conduct this study. Results : The change rate of water content by ischemia in the normal group was 78.90% on the third day and 79.12% on the seventh day after an attack of ischemia. The rate in the control group was 80.34% and 81.72%. In the sample group the rate was 79.85% and 80.97%. This is a significant result. According to the result of the optical microscopic examination, the cells seen to be continuous and systematic in the pyramidal cells of hippocampus were changed into discontinuous and unsystematic forms in the control group. But compared with the control group, the cells were less damaged in the sample group. Conclusions : The data shows that the effect of Boyanghwano-tang Extracts on Reversible Forebrain Ischemia in MG is a significant result.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.363-370
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• 2007

Mongolian gerbil (Meriones unguiculatus) has been as an model animal for studing the neurological disease such as stroke and epilepsy because of the congenital incompleteries in Willis circle, as well as the investigation of water metabolism because of the long time-survival in the condition of water-deprived desert condition, compared with other species animal. Aquaporin 2 (AQP2) expressed at the surface of principal cells in collecting duct results from an equilibrium between the AQP2 in intracellular vesicles and the AQP2 on the plasma membrane. Aquaporin 4 (AQP4), which is expressed in cell in a wide range of organ, is also present in the collecting duct principal cells where this is abundant in the basolateral plasma membranes and represent potential exit pathways from the cell for water entering via AQP2. In this research, we divide 3 groups of which each group include the 5 animals. In the study of 7 or 14 days water restricted condition, we investigated the AQP2 and AQP4 by using a quantitative immunohistochemistry in the kidney. The results obtained in this study were summarized as followings. AQP2 is abundant in the apical plasma membrane and apical vesicles in the collecting duct principal cell and at rare abundance in connecting tubules. In the water-deprived Mongolian gerbil kidney, expression of AQP2 was continuosly increased in the cortical collecting duct and inner medullary collecting duct. This increase was both the apical region and cytoplasm. AQP4 is mainly expressed in the inner medulla, although some expression is also noted in the more proximal segment. In the water-deprived Mongolian gerbil kidney, AQP4 was also increased in the inner medullary collecting duct. Immunoactivity was increased in entire inner medullary collecting duct and newly detected in cytoplasm of principal cell. These findings suggest that increased levels of AQP2 and AQP4 in the cortical and inner medulalry collecting duct may play a important role for maintain fluid balance in the water-deprived kidney.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.05a
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• pp.120-120
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• 2001

방사선 조사는 생물체의 여러 장기에 큰 손상을 일으키며 생식기에도 큰 영향을 미치는 것으로 알려져 있다. 이중 숫컷의 고환내의 분화중인 정모세포는 매우 민감함을 나타내며 그 결과 방사선 조사 정도에 따라 정자의 이상 형태 및 정자수의 감소를 나타내어 무정자증까지 초래할 가능성이 있는 것으로 알려져 있다. 본 실험에는 8주된 Mongolian gerbil 숫컷을 사용하여 5Gy 및 10 Gy(선량률 ： 1 Gy/분)를 조사하였으며 방사선 조사 바로 직후 및 7일에 고환을 채취하였다. (중략)

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.317-322
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• 2003

TrkA is an essential component of the high affinity NGF receptor necessary to the mediate biological effects of the neurotrophins NGF. Here we report on the expression of TrkA in the olfactory bulb and basal nucleus of Mongolian gerbil brain during the postnatal development. The expressions of TrkA were identified in a immunohistochemical method. Higher levels of TrkA immunoreactivity were detected in septum than that in olfactory bulb and caudate putamen (CPu). But TrkA was not observed before postnatal days (PND6) in olfactory bulb and PND9 in CPu. No TrkA-positive cell was detectable in the olfactory fiber layer. Several regions, such as olfactory bulb and CPu, showed weak labeling. These data show that expression of TrkA is developmentally regulated during postnatal Mongolian gerbil brain development and suggest that high affinity neurotrophinreceptors mediate a transient response to neurotrophins in many regions during the brain ontogeny.

• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.147-155
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• 2001

The immunocytochemical localization of tyrosine hydroxylase(TH) is examined in the developmental forebrain of mongolian gerbil in order to determine changes in the distribution and cytology of neurons. At each of the different developmental stage, including prenatal(E)14, E16, E18, E20, postnatal(P)0, P2, P4 days, mongolian gerbils were sacrificed. In E14, TH-IR cells were predominantly round or oval in shape and their processes were very short. In olfactory blub, TH-IR cells were begun to appear from E20. In the striatum, we observed only fibers of TH-IR at all ages. From E16, TH-IR perikarya and fiber were present in periventricular nucleus and paraventricular nucleus of hypothalamus. The changes from the early to the late prenatal stages of development appear to be the result of an increase in number of TH-IR perikarya and processes. These results were shown slight differences to other rodents.

• Applied Microscopy
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• v.37 no.4
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• pp.271-280
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• 2007

Tonicity-responsive enhancer binding protein(TonEBP) is a transcriptional factor essential in the function and development of the renal medulla. TonEBP plays a critical role in protecting renal medullary cells from the deleterious effect of hypertonicity. TonEBP is a key regulator of urinary concentration via stimulation of transcription of urea transporter(UT) in a manner independent of vasopressin. UT in the renal inner medulla is important for the conservation of body water due to its role in the urine concentrating mechanism. Mongolian gerbil(Meriones unguiculatus) has been as an model animal for studying the neurological disease such as stroke and epilepsy because of the congenital incomplete in Willis circle, as well as the investigation of water metabolism because of the long time-survival in the condition of water-deprived desert condition, compared with other species animal. In this study, we divide 3 groups of which each group include the 5 animals. In the study of 7 or 14 days water restricted condition, we investigated the TonEBP and UT-A by using a immunohistochemistry in the kidney. In the normal kidney, the distribution of TonEBP is generally localized on nuclei of inner medullary cells. Nuclear distribution of TonEBP is generally increased throughout the medulla in 7 and 14 days dehydrated group compared with control group. Increased nuclear localization was particularly dramatic in thin limbs. In control groups, UT-A was expressed in inner stripe of outer medulla(ISOM) and inner medulla(IM). UT-A was present in the terminal part of the short-loop of descending thin limbs (DTL) in ISOM and also present in the inner medullary collecting duct(IMCD), where the intensity of it gradually increased toward the papillary tip. In the dehydrated kidney, UT-A immunoreactivity was increased in the short-loop of DTL in ISOM and in the long-loop of DTL in the initial part of IM, where was expressed moderate positive reaction in the normal kidney. Also it was up regulated in the IMCD in initial & middle part of IM. However UT-A down regulated in the IMCD, where the intensity of it gradually decreased toward the papillary tip. These findings suggest that increased levels of TonEBP in medulla and UT-A in shot-loop of DTL and IMCD play a important role for maintain fluid balance in the water-deprived mongolian gerbil kidney.

• BMB Reports
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• v.46 no.2
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• pp.80-85
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• 2013

We investigated the temporal alterations of adrenocorticotropic hormone (ACTH) immunoreactivity in the hippocampus after seizure onset. Expression of ACTH was observed within inter-neurons in the pre-seizure group of seizure sensitive gerbils, whereas its immunoreactivities were rarely detected in seizure resistant gerbil. Three hr after the seizure, ACTH immunoreac-tivity was significantly increased in interneurons within all hippocampal regions. On the basis of their localization and morphology through immunofluorescence staining, these cells were identified as $GABA_A$ ${\alpha}1$-containing interneurons. At the 12 hr postictal period, ACTH expression in these regions was down-regulated, in a similar manner to the pre-seizure group of gerbils. These findings support the increase in ACTH synthesis that contributes to a reduction of corticotrophin-releasing factor via the negative feedback system which in turn provides an opportunity to enhance the excitability of GABAergic interneurons. Therefore, ACTH may play an important role in the reduction of excitotoxicity in all hippocampal regions.

• Parasites, Hosts and Diseases
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• v.40 no.4
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• pp.181-186
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• 2002

To examine the fate of Strongyloides venezuelensis, Mongolian gerbils (Meriones unguicalatus) were orally infected with 1,000 $L_{3}$ larvae per animal. Altogether, 50 gerbils divided into 5 groups of 10 each were monitored for a period of 570 days to document the kinetics of faecal egg output, adults worm population, morphological development, fecundity, and hematological changes including peripheral blood eosinophilia. This study chronicled a life long parasitism of S. venezuelensis in the gerbil host, and showed that S. venezuelensis infection was quite stable throughout the course of infection and the worms maintained their normal development as evidenced by their body dimension. A progressive loss of body condition of the infected gerbils was observed as the level of infection advanced. However, no detectable pathological changes were observed in the gastrointestinal tract. The present findings indicate that an immunocompetent host, such as the Mongolian gerbil, can serve as a life long carrier model of S. venezuelensis if the worms are not expelled within 570 days after infection.