This study was observed of the skin that changed after irradiation of the ultraviolet A. All the mouse were hairless which the weight are about 25g and the ages $6\sim8$ weeks old. The mouse were divided into six groups; control, irradiated for 6 hours, 3 days, 7 days, 14 days, 21 days and 28 days. Each group was irradiated with ultraviolet that is $320nm\sim366nm$ of wavelengths. After irradiated, the skin was observed with the electron microscope and the light microscope. The results are as follow: 1) Light microscopy With following irradiation, the epidermis was not changed to most groups but at the 28 days group was thickened and deposit the melanocyte. The elastic fibers within the epidermis were thickened and twisted with following irradiation. 2) Eelectron microscopy The elastic fibers were slightly clumped at 6 hours group, mildly increased and partly aggregated in the 3 days group, branched and tangled at 7 days group, irregulated and electron density at 14 days group, sightly thickened and twisted at 21 days group, and randomly arranged, shortened, twisted, and electron density at 28 days group.

The development of the superior cervical ganglion was studied by electron microscopic method in human fetuses ranging from 40 mm to 260 mm of crown-rump length (10 to 30 weeks of gestational age). At 40 mm fetus, the superior cervical ganglion was composed of clusters of undifferentiated cell, primitive neuroblast, primitive supporting cell, and unmyelinated fibers. At 70mm fetus, the neuroblasts and their processes were ensheated by the bodies or processes of satellite cells. The cytoplasm of the neuroblast contained rough endoplasmic reticulum, mitochondria, Golgi complex, Nissl bodies and dense-cored vesicles. As the neuroblasts grew and differentiated dense-cored vesicles moved away from perikaryal cytoplasm into developing processes. Synaptic contacts between the cholinergic axon and dendrites of postganglionic neuron and a few axosomatic synapses were first observed at 70 mm fetus. At 90 mm fetus the superior cervical ganglion consisted of neuroblasts, satellite cells, granule-containing cells, and unmyelinated nerve fibers. The ganglion cells increased somewhat in numbers and size by 150 mm fetus. Further differentiation resulted in the formation of young ganglion cells, whose cytoplasm was densely filled with cell organelles. During next prenatal stage up to 260 mm fetus, the cytoplasm of the ganglion cells contained except for large pigment granules, all intracytoplasmic structures which were also found in mature superior cervical ganglion. A great number of synaptic contact zones between the cholinergic preganglionic axon and the dendrites of the postganglionic neuron were observed and a few axosomatic synapses were also observed. Two morphological types of the granule-containing cells in the superior cervical ganglion were first identified at 90 mm fetus. Type I granule-containing cell occurred in solitary, whereas type II tended to appeared in clusters near the blood capillaries. Synaptic contacts were first found on the solitary granule-containing cell at 150 mm fetus. Synaptic contacts between the soma of type I granule-containing cells and preganglionic axon termials were observed. In addition, synaptic junctions between the processes of the granule- containing cells and dendrites of postganglionic neuron were also observed from 150 mm fetus onward. In conclusion, superior cervical ganglion cells and granule-containing cells arise from a common undifferentiated cell precursor of neural crest . The granule-containg cells exhibit a local modulatory feedback system in the superior cervical ganglion and nay serve as interneurons between the preganglionic and postganglionic cells.

The glandular secretory system of the capitate gandular trichomes in leaf of Thymus quinquecostatus Celakovsky was examined by transmission electron microscope. The glandular trichome was consisted of three cell layers; an basal cell layer, a stalk cell with single-celled intermediate layer and a discoid secretory layer with thickened cuticle. The secretory cell was dense, rich in mitochondria, rER, plastds, Golgi complex and had many vesicular structure. Typical plastids with reticulate body and plastoglobule were present in glandular trichome. The tytoplasm of secretory cell was filled with osmiophilic secretory materials. The secretory vesicles, originated from Golgi complex, appeared as membrane bounded vesicles and secreted to the outer wall surface. The presences of well developed rER, mitochondria, Golgi complex, and membrane-bounded vesicles fused with plasmalemma in the secreting cells indicate that the granulocrine mechanism of secretion was occurring in T. quinquecostatus. Subcuticular cavity was developed between the cuticular layer and the secretory cell wall, and it formed above the secretory cell upon separation of cuticle-wall.

본 연구에서는 dehydrocholic acid를 투여한 흰쥐 간세포의 vacuolar apparatus를 세포화학적으로 관찰하고자 하였다. 박절편에서 Golgi 장치의 형성면 수조는 소낭상으로 팽대된 부분이 열지어 있었으며 어떤것은 돌출되어 있었다. 이러한 소낭 모양의 돌출부는 용해소체 표면에서도 관찰되었다. 소포들은 Golgi 장치의 형성면 수조와 용해소채 및 담세관 주위에서 볼 수 있었으며 소포가 담세관에 융합되어 있는 것도 관찰되었다. 이러한 소견들은 dehydrocholic acid 투여 후 20분이 경과된 흰쥐에서 현저하였다. 정상군이나 실험군에서 거의 모든 Golgi 장치의 형성면은 담세관을 향하고 있었다. 박절편에서 Golgi 장치의 형성면 수조와 소낭 모양의 돌출부 및 소포는 가시물질을 거의 함유하고 있지 않았다. Osmium은 이들구조에서 심하게 침착되어 있었다. 용해소체와 그 주위에 있는 소포에서는 acid phosphatase 활성이 나타났다. 그러나 담세관 주위에 있는 소포에서는 osmium의 침착이나 acid phosphatase 활성이 경하게 나타나거나 관찰되지 않았다. 이러한 증거들로 미루어 소포는 Golgi 장치의 형성면과 용해소체에서 유래되며 이들소포가 담세관에 융합됨으로서 담즙산이 분비될 것으로 생각된다. 그러나 소포가 담세관에 접근해 감에 따라 소포의 효소활성은 저하되는 것 같이 보인다.

The spermatogenesis of pale chub (Zacco platypus) was investigated morphologically. The testis of pale chub contained numerous testicular sacs. These testicular sacs were bounded on neighboring sacs by single layer of squamous cells. Also, differentiated sperms were filled in the sacs. In the stage of spermatogonium, the germ cells had a large nucleus and a distinct nucleolus, and mitochondrial development was prominent. In the primary and secondary spermatogonia, these cells had a round electron-dense nucleus, reduced cytoplasm, and mitochondria were congregated in the side of cytoplasm. The highly condensed chromatin of sperms was electron-dense, the acrosome was not found in the head of the sperm and a motile flagellum consisted of an axoneme with a typical 9+2 pattern of microtubules.

The Urechis unicinctus sperm and spermatogenic cells prepared from the testis are investigated to identify $\alpha-tubulin$ of axoneme microtubules using mouse monoclonal $anti-\alpha-tubulin$ as the first Ab and Gold(10nm) conjugated goat anti-mouse IgG as the Ab marker. The Ag-Ab reaction analyzed excellently the localization of $\alpha-tubulin$ and the gold particles incorporated with the proximal and distal centrioles, manchette microtubules, and flagellum. The gold particles can be also observed in the spermatogenic cells while the cells are still in sperm ball which is composed of a somatic cell and spermatogenic cells. The sperm ball is the functional unit of sperm production in U unicinctus testis. The spermatids are developed from the spermatogenic cells in the sperm ball and released into the testis cavity through a cortical cytoplasmic opening. The spermatid architectures are similar with the mature sperm of the testis cavity in aspects of shape of discoid acrosome, degree of nuclear condensation and ring type of mitochondrion. However, the distal centriole connecting with the flagella can be observed from the mature sperm while the both proximal and distal centrioles reveal only in the spermatids. The proximal centriole is directly connected with nuclear outer membrane during the stage of nuclear condensation and oriented perpendicularly to the distal centriole whose axis coinciding with the longitudinal axis of the spermatozoon. There are indications that the distal centriole is intimately associated with the polymerization of the flagellum. The manchette microtubules appear during spermatid development but the mature sperm have round head and no conspicuous middle piece.

To investigate ultrastructural changes on the adrenal cortex of the developmental rats, tissues were collected at 20 days of gestation, at birth, 7 days, 15 days and 30 days after birth and studied by transmission electron microscopy (TEM) the mitochondrial cristae of zona reticularis in the adrenal cortex of rats were a vesicular type and the vesicles were formed prior to 20 days of gestation. Also, the numbers of vesicles were $56.2{\pm}25.3$ in 20 days of gestation, $174.0{\pm}74.7$ at birth, $127.8{\pm}74.7$ in 7 days, $87.1{\pm}40.8$ in 15 days and $86.7{\pm}53.8$ in 30 days after birth, In this study, it was identified that the vesicles of mitochondrial cristae were formed by budding. The dense bodies were also observed in the nuclei of cortex cells from 20 days of gestation to 30 days after birth.

흰쥐 부신수질의 발생에 따른 미세구조적 변화를 관찰하기 위하여 임신 20일령, 출생직후, 출생후 7일, 15일 및 30일에 각각 조직을 채취하여 전자현미경적으로 관찰한 바, 흰쥐 부신 수질에서는 과립내용물의 전자밀도가 중등도 또는 낮고, 한계막에 싸여 있으며, 한계막과 과립 내용물간에 비교적 넓은 halo를 형성하거나 얇은 core를 형성하는 원형 내지 타원형의 소위 adrenaline 과립 $(123\sim200nm)$과 과립 내용물의 전자밀도가 adrenaline 과립보다 높고 한계막과 과립내용물간에 대체로 넓은 halo를 형성하는 부정형의 소위 noradrenaline 과립 (장경 $177\sim299nm$, 단경 $124\sim194nm$) 등 두 가지 형태의 과립이 관찰되었다. 이들 두 종류의 과립은 임신 후기 및 출생직후에서는 두종의 과립이 한 세포내에서 흔재하고 있었으나, 출생후 7일령에서부터 명확한 두종의 세포를 구별할 수 있었으며 과립의 크기와 수는 일령에 따라 다소 차이를 나타내었고, 핵내에서는 치밀체가 출현하였다.

Adriamycin is a one of anthracyclin antibiotics isolated from the culture media of Streptomyces peucetius var casius. The formation of reactive oxygen metabolite by redox cycling during the metabolism and the inhibition of DNA synthesis results in antineoplastic effects of adriamycin. The authors have demonstrated the effects of SOD(superoxide dismutase) or DMTU (dimethyl thiourea), which are used as an antioxidant, on the ultrastructural changes of the gastric chief cells after the administration of adriamycin in the rat. Adriamycin (30 mg/kg) was administered intraperitoneally to the Sprague-Dawley rats weighing about 220 gm and SOD (15000 unit/kg) or DMTU (500 mg/kg) were administered intraperitoneally to the rats 30 minutes after the administration of adriamycin. The gastric chief cells 24, 48 and 72 hours after the administration of adriamycin were observed with Hitachi-600 electron microscope. The results were as follows. 1. SOD or DMTU alone did not affect the ultra structures of the gastric chief cells in the rat. 2. Dilation, sacculation and segmentation of the cisternae of rough endoplasmic reticulum, dilation of the saccules of Golgi complex and dilated mitochondria with electron lucent matrix were seen in the adriamycin treated rats. In the course of time, the ultrastructures of the chief cell changed markedly. 72 hours after drug administration, severely dilated cisternae of rough endoplasmic reticulum, with clumping of chromatin around the nuclear envelope and mitochondria with electron lucent matrix and dilated cristae were seen in the chief cell. 3. The treatment of SOD is more effective than DMTU to attenuated the ultrastructural changes of the chief cells in the adriamycin administered rat. Consequently it is suggested that adriamycin would induce the degenerative changes of the organelles of the chief cell. The treatment of SOD is more effective than DMTU to attenuate the adriamycin induced damage.

The structures of the fertilizedegg envelope in threespecies of cyprinidae, leoparddanio (Brachydanio frankei), cherry barb (Barbustitteya) and white cloudmountain fish (Tanichthys albonubes) were investigated by light and electron microscopy. The fertilized eggs of all three species have colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropylewhich is thought to the pathway of sperm in the area of the animal pole. Also, an outer layersof both cherry barband white cloud mountain fish areadhesive types, but in that of leoparddanio has non-adhesivetype. In leopard danio, an outer surface ofegg envelope is covered by mushroom-likestructure, that of cherry barb is arranged by button-like structure, and that of white cloud mountain fish isarranged by rod-likestructure. Inboth leopard danioand cherrybarb, the eggenvelopes consist of three distinct layers; an outer layer, a middle layer and an inner layer, and that of white cloud mountain fish hastwo layers. An innerlayer of egg envelopein leopard danio consist of 10 layers, cherry barb has 8 layers, and white cloud mountain fish has $5\sim6$ layers.