• The Journal of Korean Medicine
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• v.27 no.4
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• pp.125-134
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• 2006

During the prenatal period, the development of the individual is influenced by a host of environmental factors. Exposure to noise stress during pregnancy was determined to result in the retardation of growth, a reduction in neurogenesis, and an impairment of spatial learning ability in the rat pups. In the present study, we have attempted to characterize the effects of prenatal treatment with Cnidium officinale Makino on spatial memory and neurogenesis in the hippocampus of rat pups born from maternal rats exposed to noise stress during pregnancy. Prenatal treatment with Cnidium officinale Makino was shown to increase neurogenesis and enhanced spatial learning ability in rat pups born from maternal rats exposed to noise stress. In this study, we have determined that prenatal treatment with Cnidium officinale Makino can stimulate spatial development and neurogenesis in the brain of the fetuses exposed to prenatal stresses.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1291-1296
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• 2007

The expressions of c-Fos and nitric oxide synthase (NOS) represent neuronal activity and play' a crucial role in the shaping of the development of brain. During the late pregnancy, stresses may influence neuronal activity of prenatal rats. In the present study, the effects of prenatal noise and music on the expressions of c-Fos and NOS in the hippocampus of rat pups were investigated. Exposure to the noise during pregnancy decreased c-Fos and NOS expressions in the hippocampus of rat pups, whereas exposure to music during pregnancy increased c-Fos and NOS expressions in the hippocampus of rat pups. The present results show that prenatal music stimulation may increase neuronal activity of rat offspring, whereas exposure to noise during pregnancy may reduce the neuronal activity of offspring. The present study suggests that prenatal stimuli including noise and music could affect the fetal brain development.

• Journal of Nutrition and Health
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• v.28 no.7
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• pp.602-611
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• 1995

This study was designed to find out the effects of $\omega$-3 and $\omega$-6 polyunsaturated and saturated fatty acid from prenatal to growing period on the brain growth and behavioral development of rats. Rats(Sprague-Dawley strain) were fed experimental diets-fish oil, corn oil or beef tallow-with different contents of $\omega$-3 and $\omega$-6 fatty acids throughout the prenatal and lactational period and up to 10 weeks of age. DNA and RNA concentration of rat brain were determined at 0, 3, 6 weeks of age and choline and acetylcholine concentrations were analyzed at 10 weeks of age. When the rats were 7 weeks of age, position reversional test in a Y-shaped water maze for 4 weeks was measured. The experimental results obtained are summarized as follows. Food intakes were significantly lower in fish oil group and body weight gain was low in the group fed beef tallow and the groups fed fish oil and corn oil were somewhat good. Food efficiency ratio was not significantly different among the groups. Brain weight was not affected by the fatty acid composition of experimental diets and DNA and RNA concentration of the rat brain were consistently maintained at the same level. It was not different significantly among the dietary groups in the DNA and RNA concentrations of the rat brain during the experimental period. The acetylcholine concentration in the fish oil group was somewhat higher than the other groups. The position reversional test in a Y-shaped water maze showed a significant difference the score of test among the experimental groups. The score of the rats fed the fish oil diet was significantly higher than the other groups and the concentration of acetylcholine in brain were too. Therefore the correlatin between the Y-shaped water maze test score and the acetylcholine concentratin in the brain was found. Above finding support the content that dietary fatty acid composition does not affect to the brain cell number and cell size but the behavior development is influenced. Therefore, the improvement of behavior development is required the effective usage of finny tribe.

• The Korean Journal of Zoology
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• v.34 no.4
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• pp.491-499
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• 1991

The present experiment was carried out 1) to study the developmental topography of GnRH neuronal system and 2) to characterize the cellular localization of GnRH neurons in the prenatal brain development of the rat. At embryonic day (I) 14.5, immunoreactive cell bodies of GnRH were first seen in the nasal septum and in the ganglion terminate located in the ventral protion of the caudal olfactory bulb. Two days later (E 16.5), GnRH-containing neurons were observed at the level of olfactory tubercle and diagonal band of Broca, which is the first appearance in the intracerebral region. From 118.5, the topographic pattern of immunoreactive GnRH perikarya was similar to that of adult rats. The present data suggest that GnRH neurons were originated from the nasal septum and gradually extended to the hvpothalamic regions with increasing fetal age.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1590-1598
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• 2008

Cell proliferation and differentiation are critical processes in a developing fetal rat brain, during which programmed cell death (PCD) also plays an important role. One of the decisive factors for PCD is Bcl-2 family proteins, where Bax induces cell death, whereas Bcl-2 acts as an inhibitor of PCD. As maternal drinking is known to cause fetal alcohol syndrome (FAS) or malformation of the fetal brain during pregnancy, the objective of the present study was to investigate whether maternal ethanol exposure alters the PCD-related Bax and Bcl-2 protein expression during fetal brain development. Pregnant female rats were orally treated with 10% ethanol and the subsequent expressions of the Bax and Bcl-2 proteins examined in the fetal brain, including the forebrain, midbrain, and hindbrain, from gestational day (GD) 15.5 to GD 19.5, using Western blots, in situ hybridization, and immunohistochemistry. With regard to the ratio of Bcl-2 to Bax proteins (Bcl-2/Bax), the Bax protein was dominant in the forebrain and midbrain of the control GD 15.5 fetuses, except for the hindbrain, when compared with the respective ethanol-treated groups. Moreover, Bcl-2 became dominant in the midbrain of the control GD 17.5 fetuses when compared with the ethanol-treated group, representing an alternation of the natural PCD process by ethanol. Furthermore, a differential expression of the Bcl-2 and Bax proteins was found in the differentiating and migrating zones of the cortex, hippocampus, thalamus, and cerebellum. Thus, when taken together, the present results suggest that ethanol affects PCD in the cell differentiation and migration zones of the prenatal rat brain by modulating Bax and Bcl-2 expression in an age- and area-dependent manner. Therefore, this is the first evidence that ethanol may alter FAS-associated embryonic brain development through the alteration of Bax and Bc1-2 expression.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.6
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• pp.293-297
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• 2002

The role of 5-hydroxytryptamine $(5-HT)_1A$ receptor activity in prenatal ischemia was studied, by injecting 8-hydroxy-dipropylaminotetraline (8-OH-DPAT; $50{\mu}g/kg,$ s.c.), a $5-HT_1A$ agonist on gestation day 17, and 30 min later inducing transient ischemia by ligating the uterine vessels for 30 min. On postnatal day 95, rats that had experienced prenatal ischemia showed impaired motor coordination and reduced concentration of 5-HT in the cerebellum compared with Sham-operated controls. In addition, they showed increased $5-HT_1A$ receptor densities in the cerebral cortex. Pretreatment with 8-OH-DPAT ameliorated the behavioral and neurochemical sequelae measured in the present study. The results suggest that $5-HT_1A$ receptors protect the brain from ischemic insult and/or facilitate recovery after prenatally experienced ischemia.

• The Korean Journal of Zoology
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• v.36 no.2
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• pp.209-222
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• 1993

The present study attempts to explore the first appearance 8nd subsequent development of %cosine hvdroxvlase (TH)-containing neurons in the rat brain from embryonic day (E) 10.5 to the neonate. To increase the senti노ivity and resolution power, a double bridge peroxidase-anti-peroxidase technique was employed for cellular localization of TH. In situ hybridization histochemistw with synthetic TH oligomer (30-mer) codinB TH was also used to detect TH mRNA. TH-containing neurons were first detected at E11.5 in the intermediate zone of prosencepha1on and mesencephalon. At this stage, TH-immunoreactive neurons were small, ovoid bee and emitted their fibres into their immediate surroundings. From this stage, TH-immunoreactive neurons increased in their number and underwent migration and cell differentiation. At E15.5, the distribution pattern of the maior groups of TH neurons was similar to that of adult catecholaminergic groups, and at E19.5 the external laver of median eminence showed TH-immunoreactive processes.

• Korean Journal of Exercise Nutrition
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• v.13 no.1
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• pp.23-28
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• 2009

The expression of c-Fos and c-Jun represents neuronal activity and plays a crucial role in the shaping of the development of brain. During the late pregnancy, exercise is known to influence neuronal activity of offspring. In the present study, the effect of swimming during pregnancy on the expression of c-Fos and c-Jun in the CA1, CA2, CA3 regions, and the dentate gyrus of the hippocampus of rat offspring was investigated using immunohistochemistry. Pregnant rats in the swimming group were forced to swim for 10 min once a day from 15 days after pregnancy until delivery. The expression of c-Fos and c-Jun in the CA1, CA2, CA3 regions, and the dentate gyrus of the hippocampus of pups was significantly increased by maternal swimming during late pregnant period. The present results show that prenatal swimming may enhance the neuronal activity of pups and affect the neonatal brain development.

• Development and Reproduction
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• v.12 no.2
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• pp.117-124
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• 2008

The efficient strategies to cope with unpredictable and/or harmful environmental changes have been developed by every organism in order to ensure its survival and continuity of it's own species. As a results, all living things on earth maintain dynamically internal stability via a process termed 'homeostasis' among physiological parameters despite of external environment changes. Stress is an emotional and physical response to threat homeostasis. Stress may have not only transient but rather permanent effect on the organism; recent evidence clearly show that prenatal stress could organize or imprint permanently physiological systems without any change in genetic codes, a process known as 'epigenetic programming'. In this review, a series of reproduction-associated events occurred in prenatally stressed male rats such as alteration in the structure of sexually dimorphic brain regions, modification of neurotransmitter metabolism, changes in reproductive endocrine status, and finally, disorders of sexual behavior will be introduced. The fetal brain is highly sensitive to prenatal programming and glucocorticoids in particular have powerful brain-programming properties. The chronic hyperactivation of fetal brain by maternal stress-induced glucocorticoid input will provide new program via increasing the neuroplasticities. This 'increased neuroplasticities' will be the basis for the 'increased phenotypic plasticities' rendering the organism's better adaptation to environmental challenges. In conclusion, organism who experienced 'harsh' environment in his fetal life seems to give up a certain portion of reproductive competence to make good chance of survival in his future life by epigenetic (re)programming.

• Development and Reproduction
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• v.4 no.1
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• pp.95-100
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• 2000

A large number of man-made chemicals that have been released into the environment have the potential to disrupt the endocrine system of animals and humans. There is a critical developmental period during which sexual brain differentiation proceeds irreversibly under the influence of gonadal hormone. Recently we identified KAP3 gene expressed during the critical period of rat brain sexual differentiation. KAP3 functions as a microtubule-based motor that transports membranous organelles anterogradely in cells, including neurons. In the present study, we aimed to investigate the effect of endocrine disrupter, Dichlorodiphenyl trichloroethane (DDT), on the KAP3 gene expression during critical period of rat brain development. Maternal exposure to DDT increased the level of KAP3 mRNA in male and female fetus brains when examined on the gestational day 17 (GDl7). In postnatal day 6, DDT suppressed the expression of KAP3 gene in male and female rat brain. Also, the body weight and fertilization rate were decreased in the DDT exposured rats. These results showed that endocrine disrupter, DDT, can affect the transcriptional level of brain sexual differentiation related gene, KAP3, in the prenatal and the neonatal rat brain and that maternal exposure to endocrine disruptors may lead to a toxic response in embryonic differentiation of brain. And so KAP3 gene may be used a gene maker to analyse the molecular mechanism for toxic response in animal nerve tissues exposed to endocrine disruptors.