Chin Med J (Taipei) 1998;61:S43.

Mechanism of Fertilization and Assisted Reproductive Technology

Masahiko Hiroi, M.D., Ph.D.

Yamagata University School of Medicine, Yamagata, Japan

Abstract

Fertilization is the process including many events whereby individual gametes from the female and male unite to create offspring. However the mechanism of fertilization is still not clearly understood. In this lecture following topics will be discussed.

(1) Follicular development and ovum maturation are controlled by both pituitary gonadotropins and local factors such as autocrine and paracrine agent. A mature follicle fluid supress aromatization from androstendione to estradiol. Apoptosis of granulosa cells and ovum are related to fertilization. Apophotic bodies in granulosa. of human follicles was highly observed in aged group over 40 years.

(2) Fertilization triggered facilitative 2-deoxyglucose transport in one-cell embryo, and 2-deoxyglucose 6-phosphate formation developed along with the maturation of preimplantation embryos.

(3)Intracellular calcium concentration starts to increase in a periodic manner after fertilization in docytes of mice. This calcium oscillation was inhibited by Calcium channel antagonists and pattern of Calcium oscillation was changed in older egg compared to fresh egg.

(4) Analysis of sperm chromosome was correctly performed after microinjection of sperm into hamster oocytes even oligo-asthenozospermia of human.

(5) The oviduct secretes specific glycoprotein that associate with egg after ovulation. Molecular cloning of cDNA corresponding to hamster oviduct glycoprotain was eight potential N-glycolsylation sides. Northern blot analysis revealed a single message.

(6)infertile couples are willing to get their babies, but they are stressfully influenced and emotionally unstable. Assisted reproductive technology such as IVF-ET, microinsemination of sperm into oocyte are widely used in Japan.

Our results and also collected data in Japan will be presented.

[Chin Med J (Taipei) 1998;61:S43.]