| HOME | HELP | CONTACT US | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
tysonkaIn the first experiment, mature female Wistar rats, displaying a regular 4-day oestrous cycle, were killed in succession every 2 or 3 h on the day of pro-oestrus and oestrus until the time of ovulation. In the second experiment, immature female Wistar rats (aged 24 days) were injected s.c. with 30 IU pregnant mare serum gonadotrophin (PMSG) and 56 h later with 20 IU human chorionic gonadotrophin (hCG). They were killed in groups at 0, 24, 48, 56 and 57 h, and then every 2 h until 72 h. Excised ovaries were homogenized and analysed for steroid content or they were submitted to a routine histological procedure. The cyclic and PMSG/hCG-treated rats exhibited some similarities and differences in the general pattern of steroid content. Either a presumptive endogenous LH surge or administration of hCG resulted in an increase in the ovarian androgen concentration which preceded a rise in progesterone; the progesterone peak, in turn, was accompanied by a fall in the amount of androgens and oestradiol. However, in comparison with cyclic rats, superovulated animals displayed a significantly higher ovarian androgen level for a prolonged period; ovarian oestradiol concentration was also raised while the progesterone content was much lower. Histological analysis revealed large differences between the ovaries of superovulated and cyclic rats, especially with regard to the maturing follicles. The majority of PMSG/hCG-derived follicles showed hypertrophied theca interna and degenerated or luteinized granulosa. A large number of preovulatory follicles did not ovulate. These results clearly indicate that PMSG/hCGinduced follicles are not equal to the follicles developing during a normal oestrous cycle. This should be taken into consideration when using superovulated animals in experiments.
Journal of Endocrinology (1994) 141, 91–100
This article has been cited by other articles:
|
|
 |
|
  R. Roberts, J. Stark, A. Iatropoulou, D. L. Becker, S. Franks, and K. Hardy Energy Substrate Metabolism of Mouse Cumulus-Oocyte Complexes: Response to Follicle-Stimulating Hormone Is Mediated by the Phosphatidylinositol 3-Kinase Pathway and Is Associated with Oocyte Maturation Biol Reprod, July 1, 2004; 71(1): 199 - 209. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. M.H. Combelles and D. F. Albertini Assessment of Oocyte Quality Following Repeated Gonadotropin Stimulation in the Mouse Biol Reprod, March 1, 2003; 68(3): 812 - 821. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Sekiguchi, T. Mizutani, K. Yamada, T. Yazawa, H. Kawata, M. Yoshino, T. Kajitani, T. Kameda, T. Minegishi, and K. Miyamoto Transcriptional Regulation of the Epiregulin Gene in the Rat Ovary Endocrinology, December 1, 2002; 143(12): 4718 - 4729. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Van Blerkom and P. Davis Differential effects of repeated ovarian stimulation on cytoplasmic and spindle organization in metaphase II mouse oocytes matured in vivo and in vitro Hum. Reprod., April 1, 2001; 16(4): 757 - 764. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. L. Chaffin and R. L. Stouffer Role of gonadotrophins and progesterone in the regulation of morphological remodelling and atresia in the monkey peri-ovulatory follicle Hum. Reprod., December 1, 2000; 15(12): 2489 - 2495. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. K. Deol, R. Varghese, G. F. Wagner, and G. E. DiMattia Dynamic Regulation of Mouse Ovarian Stanniocalcin Expression during Gestation and Lactation Endocrinology, September 1, 2000; 141(9): 3412 - 3421. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | CONTACT US | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
