An Immunohistochemical Study on the Macrophages in the Developing Corpora Lutea of the Rat / 대한해부학회지

Within the corpus luteum, macrophages exert luteotropic and luteolytic actions through secretion of TNF-alpha. However, the mechanisms of luteotropic actions on the development and maintenance of pregnant and nonpregnant corpora lutea are thoroughly unknown.In this experiment, TUNEL, macrophage, and TNF-alpha immunohistochemistry on the corpora lutea of pregnant and nonpregnant rats (Sprague-Dawley strain) were carried out to reveal the role of macrophages in the developing corpora lutea. The results were as follows; 1) In the nonpregnant corpora lutea, the number of macrophages was increased significantly, and the degree of ED1-immunoreactivity of macrophages was increased moderately. But lutein cells showed low-degree TNF-alpha-immunoreactivity. 2) In the pregnant corpora lutea, the number of macrophages was decreased significantly, and the degree of ED1- immunoreactivity of macrophages was low. But lutein cells showed moderate-degree TNF-alpha-immunoreactivity. Based on the above results, it was considered that macrophages in the nonpregnant corpora lutea exert phagocytic action mainly, and the macrophages in the pregnant corpora lutea exert TNF-alpha-secreting action to maintain the structure and function of lutein cells.

Changes of Apoptosis After X-irradiation During the Hindlimb Development in the Rat Fetus / 체질인류학회지

Ionizing radiation exerts harmful effect during the limb development, but the exact mechanism is still largely unknown. In this study, 2 Gy of X-ray irradiated to the rat fetuses on gestation day of 13.7 when the hindlimb buds appear, and sacrificed at GD 14.7, GD 15.7 and GD 16.7, respectively. To reveal the changes of apoptotic figures between control and experimental groups, TUNEL immunohistochemistry and confocal laser scanning microscopy were carried. Mean body weight of fetuses of irradiated groups were decreased significantly compared to the control group. Numerical digit anomalies and asymmetries between right and left sides were increased significantly in the irradiated group compared to control group. Some digit anomalies were increased significantly in the right side. Radiation-induced decrement of the density of apoptotic figures on GD 14.7 was presumed to be related with foot and digit anomalies.

Macrophages in the Corpus Luteum of the Rat : Immunohistochemical and Transmission Electron Microscopic Study / 대한해부학회지

Macrophages in the corpus luteum have many important roles during the periods of functional development and luteal regression. Not only phagocyte the apoptotic luteal cells, but also they secrete many cytokines and exert their effects via autocrine/paracrine actions.In this study, we investigated the changes of number and immunoreactivity of macrophages at various developmental periods of the corpus luteum in the rat ovary. The rats (Sprague-Dawley strain, female)at age of 8 weeks (ovulatory period), GD 6 (pregnant period), and postpartum 5 days (postpartum period)were sacrificed under ether anesthesia and obtained both ovaries, one used for macrophages immunohistochemistry and the other used for TEM. The results were as follows; 1.In the corpora lutea of the rat, macrophages were observed all the developmental periods including ovulatory, pregnant and postpartum periods. 2.In the corpora lutea of the rat, number of macrophages was highest in the ovulatory period, and decreased at postpartum period and pregnant period in order. The immunoreactivity of macrophages was high at ovulatory period, moderate at postpartum period, and low at pregnant period. 3.In TEM observations, two types of macrophages were observed: One type was non-phagocytic macrophage and the other type was phagocytic macrophage. Phagocytic macrophages were observed in the corpora lutea at ovulatory and postpartum periods and contained apoptotic bodies, phagocytic vacuoles and many lipid droplets. Non-phagocytic macrophages were observed in the corpora lutea at pregnancy period and showed slender cell body with long cytoplasmic processes and contained no apoptotic bodies. In the rat, the number and the degree of immunoreactivity of macrophages in the corpus luteum varied with the changes of functional state of the corpus luteum. It was suggested that the main function of the macrophages at the ovulatory and postpartum periods was elimination of apoptotic luteal cells and that at pregnancy period was autocrine/paracrine action.Ultrastructurally, two types, phagocytic and nonphagocytic types, of macrophages confirmed. These results will provide valuable informations on the study of the role macrophages during development and regression of corpus luteum.

Morphological Study on the Arterial Intimal Hyperplasia and the Inhibitory Action of Dexamethasone / 체질인류학회지

This study is performed to reveal the changes of the arterial wall, especially, tunica intima and tunica media, after endothelial denudation and the effects of dexamethasone sodium on intimal hyperplasia morphologically in the rat. After arterial denudation by modified air drying technique, dexamethasone 1, 200 mg/kg/day was administered intramuscularly daily from the day of operation for 14 days. At 5 DAT (days after treatment) and 14 DAT, tunica intima was greatly thickened in control groups compared with normal group, but not in the dexamethasone-treated groups. Light microscopically, greatly increased cells and intercellular matrix in the tunica intima are observed in control group, but not in the dexamethasone-treated group. In the TEM observation, the cells considered as myofibroblasts and extracellular matrix were greatly increased in both tunica intima and tunica media just below the internal elastic lamina in the control group. Myofibroblasts and extracellular matrix migrated through the apertures of internal elastic lamina into the endothelial layer. Characteristic false internal elastic lamina also found. In dexamethasone-treated group, myofibroblasts and extracellular matrix decreased significantly, and apoptotic electron-dense cells, fragmented nucleus and autophagic vacuoles are observed. Through the apertures of internal elastic lamina, comma-shaped fragmented nuclei migrated into the tunica intima. These results suggest that dexamethasone inhibits the myofibroblast-transformation and proliferation of smooth muscle cells, migration of myofibroblasts and matrix synthetic activity, and induces the apoptosis of smooth muscle cells under the internal elastic lamina.

The Effect of X -irradiation on Lens Development / 체질인류학회지

For the study the effects of X -ray irradiation on the development of lens and interactions between optic vesicle and lens, 200 rads X -ray irradiated to the preganat rats (Sprague -Dawley strain) on gestation day 9.5. The rats were sacrificed daily from the gestation day 10.5 to 17.5, and investigated the development of lens with light microscope. The results were as follows; 1. The survival rate of X -irradiated rat fetuses was decreased significantly compared with that of the control group. 2. The mean body weight of the X -irradiated rat fetuses was decreased significantly compared with that of the control group. 3. The congenital anomalies of the eye in the rat fetuses after X -irradiation were anophthalmia, congenital aphakia, lens aplasia, lens luxation, and coloboma of the retina. 4. The critical period of lens development of the Sprague -Dawley rats was considered from GD 9. 5 to GD 10.0. 5. In the X -irradiated rat fetuses on gestation day 9.5, optic vesicle did not developed, but lens developed independently , and moved deeply toward the forebrain vesicle. According to above results, it could be concluded that the development of lens from surface ectoderm might be independent from the inductive influence of optic vesicle, and the movement of lens toward the forebrain vesicle could be mediated by chemotactic factors secreted from the brain vesicle. Further studies are needed to reveal the mechanisms of lens development and interaction between lens and brain vesicle.