Development of embryos in superovulated guinea pigs following active immunization against the inhibin alpha-subunit.
Embryo recovery and subsequent embryonic development from guinea pigs treated with or without inhibin vaccines were compared to determine the effect of active immunization against the inhibin alpha-subunit. Twenty female guinea pigs of the Hartley strain were injected 3 times either with 1 ml inhibin vaccine (recombinant ovine inhibin a-subunit in oil emulsion: 50 microg/ml, inhibin-immunized group), or 1 ml placebo (saline in oil emulsion; control group) at 4 week intervals. After one estrous cycle following the last injection, females were naturally mated and embryos were collected at 11:00 hr of day 6 of pregnancy (Day 1: sperm in the vaginal smear) for culture in vitro. Active immunization increased the number of corpora lutea (12.6+/-3.0 vs. 4.6+/-0.2, P<0.05), recovered embryos (9.8+/-1.9 vs. 3.6+/-0.4, P<0.01) and normal embryos (7.8+/-1.4 vs. 3.6+/-0.4, P<0.05), although estrous cycle length was not affected (P>0.05). During subsequent 8 day culture in vitro, most of the recovered embryos formed trophoblast outgrowth; 100% (14/14) and 88.2% (15/17) in control and immunized groups, respectively. High levels of inhibin antibody titers were sustained in the inhibin-immunized guinea pigs at least for 5 months after the last injection while no antibody titer was detected in the control animals. These results indicate that active immunization against the inhibin a-subunit is a long-acting and efficient method to induce superovulation with normal embryonic development in the guinea pig.
Shi
F
F
Laboratory of Veterinary Physiology, Tokyo University of Agriculture and Technology, Japan.
Mochida
K
K
Suzuki
O
O
Matsuda
J
J
Ogura
A
A
Tsonis
C G
CG
Watanabe
G
G
Suzuki
A K
AK
Taya
K
K
D000818:Animals; D000917:Antibody Formation; D005314:Embryonic and Fetal Development / Q000276:immunology*; D004958:Estradiol / Q000097:blood; D004971:Estrus / Q000502:physiology; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006168:Guinea Pigs; D007265:Inhibins / Q000276:immunology*; D011374:Progesterone / Q000097:blood; D012726:Sexual Behavior, Animal / Q000502:physiology; D013480:Superovulation / Q000502:physiology; D014611:Vaccination / Q000379:methods
D011374:Progesterone; D004958:Estradiol; D007265:Inhibins; D005640:Follicle Stimulating Hormone