The present study was designed to look at the effect of epidermal growth factor (EGF) and tomcie-stimulating hormone (FSH) on initiation of primordial follicle growth and differentiation in the ovary of newborn rat wi...The present study was designed to look at the effect of epidermal growth factor (EGF) and tomcie-stimulating hormone (FSH) on initiation of primordial follicle growth and differentiation in the ovary of newborn rat with a sensitive marker of proliferating cell nuclear antigen (PCNA). The results showed that more cuboidal granulosa cells (GC) were found in the ovary two days after injection of EGF. More proliferative GC were observed on D4. No such action of FSH on primordial follicles was demonstrated. Using in situ hybridization, inhibin a mRNA expression in GC was detected from D5, while FSH receptor (FSHR) mRNA expression started from D6 after birth. Both mRNAs increased following further development of the follicles. These results suggest that it is EGF, but not FSH, that may play a certain role in initiation of primordial follicle growth. FSH may be involved in further differentiation and growth of the early developmental follicles.展开更多
By using DNA 3'-end labeling, immunocytochemistry and mRNA in situ hybridization detection techniques , the expression of inhibin subunits and LH receptor in the granulosa cells and tissue-type plasminogen activat...By using DNA 3'-end labeling, immunocytochemistry and mRNA in situ hybridization detection techniques , the expression of inhibin subunits and LH receptor in the granulosa cells and tissue-type plasminogen activator (tPA) in the oocytes has been studied in relation to follicular development and atresia. The results demonstrated that: (i) tPA activity in the oocytes of normal developing follicles is undetectable, and increases significantly in the follicle undergoing atresia; (ii) the production of inhibin subunits in granulosa cells is negatively correlated with the expression of oocyte tPA activity, indicating that they may be an important regulator of oocyte tPA production and follicular development; (iii) in atretic follicles, granulosa cells do not express LH receptor and inhibin subunits. It is therefore suggested that tPA may play a role in oocyte self-destruction and clearance in some of atretic follicles, and inhibin of granulosa-origin might be an inhibitory factor for the translation of tPA in the oocyte.展开更多
文摘The present study was designed to look at the effect of epidermal growth factor (EGF) and tomcie-stimulating hormone (FSH) on initiation of primordial follicle growth and differentiation in the ovary of newborn rat with a sensitive marker of proliferating cell nuclear antigen (PCNA). The results showed that more cuboidal granulosa cells (GC) were found in the ovary two days after injection of EGF. More proliferative GC were observed on D4. No such action of FSH on primordial follicles was demonstrated. Using in situ hybridization, inhibin a mRNA expression in GC was detected from D5, while FSH receptor (FSHR) mRNA expression started from D6 after birth. Both mRNAs increased following further development of the follicles. These results suggest that it is EGF, but not FSH, that may play a certain role in initiation of primordial follicle growth. FSH may be involved in further differentiation and growth of the early developmental follicles.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 39770099 and 39770290)Chinese Academy of Sciences and Rockefeller Foundation/WHO HPR research project.
文摘By using DNA 3'-end labeling, immunocytochemistry and mRNA in situ hybridization detection techniques , the expression of inhibin subunits and LH receptor in the granulosa cells and tissue-type plasminogen activator (tPA) in the oocytes has been studied in relation to follicular development and atresia. The results demonstrated that: (i) tPA activity in the oocytes of normal developing follicles is undetectable, and increases significantly in the follicle undergoing atresia; (ii) the production of inhibin subunits in granulosa cells is negatively correlated with the expression of oocyte tPA activity, indicating that they may be an important regulator of oocyte tPA production and follicular development; (iii) in atretic follicles, granulosa cells do not express LH receptor and inhibin subunits. It is therefore suggested that tPA may play a role in oocyte self-destruction and clearance in some of atretic follicles, and inhibin of granulosa-origin might be an inhibitory factor for the translation of tPA in the oocyte.