Sperm Capacitation after Injection of LH or HCG in Rabbits

Abstract

Sperm capacitation (1,2) in the rabbit uterus occurs more rapidly when estrogen is the predominant gonadal hormone (3). Soupart (4, 5) reported that sperm capacitation proceeds more rapidly after mating than after surgical insemination into the uterine lumen, and that an injection of 75 IU of HCG enhances sperm capacitation similarly to mating in rabbits. These observations prompted us to compare the influence of HCG with that of LH on sperm capacitation.Materials and Methods. Mature estrous rabbits of mixed breeding and weighing 3 to 5 kg were used for capacitator (6) and test rabbits. Each rabbit was caged individually for at least 1 month a t 18' with a 14-hr photoperiod before assignment to an experimen t.In any experiment, semen samples were pooled from 2 to 4 rabbits with proven fertility. Seminal plasma was discarded and the sperm were resuspended to 500 million/ml of Locke's solution with 100 pg of dihydrostreptomycin sulfate /ml. Under ether anesthesia, the uterine horns of capacitator rabbits were exposed via a midventral incision and 90 to 200 million sperm (at least 50% motile) were injected within each uterine horn near the tubouterine junction with a 26-gauge needle.

Fertilization in the Pig: Sequence of Nuclear and Cytoplasmic Events

“…In the light of recent evidence concerning aspects of capacitation in the rabbit (Soupart, 1966(Soupart, , 1967Wettemann & Hafs, 1970), the use of hcg throughout this study to induce ovulation deserves further comment. Whilst it is extremely unlikely that the population of eggs ovulated following injection of this hormone in late pro-oestrus differed significantly from that which would have ovulated spontaneously during oestrus, it is possible that hcg may exert some indirect control over the sequence of events at fertilization.…”

Chromosome Abnormalities in Rabbit Preimplantation Blastocysts Induced by Superovulation

“…Excessive administration of HCG has been reported to affect sperm capacitation in rabbits (Soupart, 1967;Wettemann & Hafs, 1970), and the development ofthe zona pellucida in baboons (Katzberg & Hendrickx, 1966). Recently, a high incidence of triploid embryos has been associated with PMSG-HCG\x=req-\ induced superovulation in mice (N. Takagi, personal communication).…”

Current research in rabbit biotechnology

“…Το ποσοστό εγκυμοσύνης ήταν 81%. Όταν η τεχνητή γονιμοποίηση και η μεταφορά εμβρύων έγιναν εναλλακτικά, διαπιστώθηκαν τα εξής: 1) Η μεταφορά εμ βρύων πέτυχε τουλάχιστον τα ίδια ποσοστά εγκυμοσύνης με την τεχνητή γονιμοποίηση (Wettemann and Hafs, 1970), 2) η μεταφορά επαναλήφθηκε χωρίς μείωση της γο νιμότητας (Illera et al, 1990) ή προβλήματα εμβρυϊκής εμφύτευσης .…”