Effect of follicle stimulating hormone dose and post-human
chorionic gonadotropin oocyte pick-up timing on oocyte development in inbred
Balb-C type female mice – a pilot study
Firdevs Gürer1, Hikmet Hassa2, H. Mete
Tanir2, Mehmet Kaya2, Ayla Eker Sariboyaci1, Fulya Kucuk1, Neval Balkose
Gunduz1, Cengiz Bal3
1Eskisehir Osmangazi University School of Medicine,
Department
of Histology and Embryology, Eskisehir, Turkey, 2Eskisehir Osmangazi University
School of Medicine, Department of Obstetrics and Gynecology, Eskisehir, Turkey,
3Eskisehir Osmangazi University School of Medicine, Department of Biostatistics,
Eskisehir, Turkey
Objective In vitro fertilisation (IVF) in rodents are good
models for human studies to determine the effective dose and timing of
gonadotropins. However, in different subspecies of rodents, the response rate
may vary. The aim of this study to find an optimal dose and timing of oocyte
pick-up (OPU) in Balb-C type female mice.
Design and methods Inbred Balb-C type
female mice were enrolled into three groups. In group I (n:6), mice weighted
18-25 gr and aged 14-16 weeks were put on ovulation induction with 30 IU
follicle stimulating hormone (FSH) intraperitoneally for 10 weeks. Fourty-eight
hours after the last dose of FSH, 30 IU human chorionic gonadotropin (hCG) was
injected. Twelve hour after OPU, oocytes were collected from the uterine horns
under stereo-microscope. In group II (n:6), FSH and hCG doses were augmented to
100 IU each and rest of the protocol remained same. In group III (n:28), 200 IU
FSH was injected intraperitoneally for 10 weeks. Forty-eight hours after the
last dose of FSH, 200 IU hCG was injected. However, OPU time was 15-17 hours
following the last hCG dose. Statistical analysis was performed by using SPPS
10.0 programme. Kruskal-Wallis Oneway ANOVA on Ranks test was applied to search
a proportion difference between groups. Post-hoc analysis was performed via
Dunn’s test.
Results Total number of oocytes collected in group I ,II and III
were 6, 46 and 434, respectively. In addition, numbers of oocyte per mouse were
1, 7.6 and 15.5, respectively (H:19.4, p<0.001, group III vs group I and II).
Conclusions Gonadotropin dose and OPU timing were important as to get an
optimal oocyte response in mice model. This study is a pilot study, in this
regard, to help the physician to monitor the drug dose and oocyte pick-up timing
to get an optimal response. Furthermore, this study points out the necessity of
planning and conducting such pilot ovulation induction studies that determine
experiment subject-specific gonadotropin dose, prior to post hCG OPU procedure,
during time-consuming rodent IVF models with high financial burden.