title: Induction of follicular luteinization by equine chorionic gonadotropin in cyclic guinea pigs.
abstract: The effects of equine chorionic gonadotropin (eCG) on follicular development and ovulation in cyclic guinea pigs were investigated by histological and immunohistochemical analyses. Three groups of guinea pigs (n=12) were administrated subcutaneously with saline, 20 or 50 IU of eCG, respectively, on cyclic Day 12 (Day 1=vaginal openings). Ovaries were collected at 4 and 8 d after administration (6 animals per group each time). The eCG administration induced significant and distinct morphological changes in the ovaries, as it promoted the luteinization of granulosa cells, but not follicular development. In addition, proliferating cell nuclear antigen (PCNA) and steroidogenic acute regulatory protein (StAR) were immunolocalized specifically in luteinized follicles. Our experiments together indicate that eCG administration can induce follicular luteinization but not superovulation in guinea pigs. The eCG in cyclic guinea pigs functions similar to that of luteinizing hormone (LH), but not follicle-stimulating hormone (FSH).
authors.affiliation: Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.|College of Agriculture and Bio-engineering, Jinhua Polytechnic, Jinhua 321017, China.
authors.forename: Jun-rong
authors.initials: JR
authors.lastname: Li
authors.affiliation: Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Laboratory of Animal Reproduction, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Fang-xiong
authors.initials: FX
authors.lastname: Shi
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D005496:Follicular Atresia / Q000187:drug effects; D006064:Gonadotropins, Equine / Q000008:administration & dosage*; D006168:Guinea Pigs; D007150:Immunohistochemistry; D034461:Luteinization / Q000187:drug effects* / Q000502:physiology; D009865:Oocytes / Q000166:cytology / Q000187:drug effects; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D010750:Phosphoproteins / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013480:Superovulation / Q000187:drug effects; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D006064:Gonadotropins, Equine; D010750:Phosphoproteins; D018809:Proliferating Cell Nuclear Antigen; D000098682:Steroidogenic Acute Regulatory Protein
keywords: Equine chorionic gonadotropin (eCG); Follicular development; Guinea Pig; Proliferating cell nuclear antigen (PCNA); Steroidogenic acute regulatory protein (StAR)