• Biomedical Science Letters
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• v.3 no.1
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• pp.1-9
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• 1997

Acrosome reaction usually occures just before fertilization in most mammals, and it has been known that $Ca^{2+}$ plays an important role in the acrosome reaction and albumin also known as a critical factor for spermatozoan activities. The present study has been designed in order to observe maturing processes of the spermatozoa occurred in the ductus epididymidis and to clarify the relationships of $Ca^{2+}$ concentrations with those processes, and to compare the enzymatic activities of ATPase and the lactate dehydrogenase of the spermatozoa in accordance with time before and after the spermatozoan maturation. From the results, we can confirm that most of the bat spermatozoa come to maturity within the epididymal cauda and may pass through capacitation outside the cauda. However it is expected to be studied that the fluctuation of spermatogenic activity depending on temperature changes and their relationships with the ductus epididymidis and their mutual influences.

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.258-272
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• 2014

Bats hibernating in caves and unused mines were surveyed during six hibernation periods (from December to February, 2005 and 2011) in Korea. We recorded 13,288 individuals of 11 species at 140 hibernacula (60 caves and 80 abandoned mines): Rhinolophus ferrumequinum (n=3,509), Eptesicus serotinus (n=6), Hypsugo alaschanicus (n=349), Miniopterus fuliginosus (n=5,919), Murina hilgendorfi (n=417), Myotis aurascens (n=294), Myotis bombinus (n=2), Myotis formosus (n=401), Myotis macrodactylus (M.mac, n=151), Myotis petax (n=2,131) and Plecotus ognevi (n=109). We studied the thermal preference and selection of hibernacula of seven dominant bat species. Four species (Myotis petax, Hypsugo alaschanicus, Plecotus ognevi and Murina hilgendorfi) hibernated mainly at the cold site below than $7^{\circ}C$, while three species (Myotis formosus, Rhinolophus ferrumequinum and Miniopterus fuliginosus) hibernated at warm site above than $7^{\circ}C$. Rhinolophus ferrumequinum had broad-ranged temperature zone for their hibernating site. The mean body temperature of each species was $2.64{\pm}0.98^{\circ}C$ for Murina hilgendorfi, $2.76{\pm}1.68^{\circ}C$ for Hypsugo alaschanicus, $2.78{\pm}0.98^{\circ}C$ for Plecotus ognevi, $4.52{\pm}1.02^{\circ}C$ for Myotis petax, $7.83{\pm}1.94^{\circ}C$ for Miniopterus fuliginosus, $9.19{\pm}2.35^{\circ}C$ for Rhinolophus ferrumequinum and $13.64{\pm}0.76^{\circ}C$ for Myotis formosus, respectively. The body temperatures of hibernating bats were closely related to the rock surface temperatures rather than the ambient temperatures. In conclusion, the diversity of bats community in hibernacula were closely related to the range of inner ambient temperature of hibernacula, and more species of bats were occupied at sites presenting a broad range of ambient temperatures.

• Applied Microscopy
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• v.29 no.2
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• pp.241-253
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• 1999

Fertilization pattern of north temperate bats is known to be unique for their sperm storage in the female reproductive tract during hibernation (e.g. Korean greater horseshoe bats). They copulate in fall but their ejaculated spermatozoa survive until the next spring. In another words they can persist to survive during long hibernation under the cold condition $(8\sim13^{\circ}C)$ and are to be fertilized with the ovum ovulated in the next spring, so called delayed fertilization. The present study was designed to observe morphological and functional changes of spermatozoa plasma membrane of the bats, hamsters which are hibernators, and mice which are non-hibernators in the room and the cold (bat-hibernation) temperatures and to confirm influence of the temperature on spermatozoa; survival rate, acrosome reaction rate, protein distribution, $Na^+-K^+-ATPase$ activities and scanning electron microscopic histochemistry. Based on the experimental results obtained in the present study, there were no significant morphological and functional differences in the spermatozoa plasma membrane in both the room and cold (bat-hibernation) temperatures and such an absence of difference suggests that the spermatozoa plasma membrane might play a pertinent role as a protector for consistent fertilization during and after hibernation.

• Applied Microscopy
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• v.30 no.4
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• pp.377-387
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• 2000

There are a few tanycytes between the general ependymal cells lining the ependymal layer of the brain ventricle. These cells are considered as modified ependymal cells which possess a long basal process. Tanycytes are known to have an ability to communicate by absorbing substances from cerebrospinal fluid and transporting them to the blood vessels and/or to the neurons in the CNS. The third and fourth ventricular tanycytes were mainly studied as subjects but it's rare to find reports about the tanycytes of the area postrema. Glial fibrillary acidic protein is an intermediate filament protein that is expressed especially in astrocytes of the CNS. But GFAP is also found in filament of the tanycytes and its process. Therefore this study was carried out for the examination of the GFAP immunoreactive tanycytes lining the area postrema of the bat, and we also examined the ultrastructure of tanycytes using electron microscope. GFAP immunoreactive tanycytes were located in the caudal portion of the fourth ventricle, and especially mainly in the transitional zone between the floor of the caudal fourth ventricle and ependymal layer lining the area postrema. A few GFAP immunoreactive tanycytes were also found in the ependymal layer lining the area postrema, and some groups of tanycytes were found in the ependymal layer of the area postrema near the floor of the caudal fourth ventricle , The processes of tanycytes were stained deeply with anti-GFAP antibody. Especially the GFAP immunoreactive tanycytes lining the area postrema had very long processes that cross the whole width of the area postrema. In the electron microscope, the cell body of ependymal tanycyte was located on the ependymal layer and had a long basal process. Intermediate filaments were observed around the nucleus and well developed in the process of tanycrte. Longitudinal oriented long mitochondria and a few lipid droplets were also found in this process. After immunocytocheical staining, the gold particles were found only in the intermediate filaments. We could not determine the function of the tanycytes in the area postrema. Thus, further investigation is required to determine the functional relationship between the tanycytes and the area postrema in hibernating animal, the bat.