Progesterone plays a critical role in canine oocyte maturation and fertilization.
Canine oocyte maturation and fertilization take place within the oviducts under increasing plasma levels of progesterone (P4). In order to investigate the role of P4 in these processes, 51 beagle bitches were treated with the P4 receptor antagonist aglepristone at the end of proestrus and 32 females were kept untreated. Fifteen treated and 13 control bitches were inseminated at Days +1 and +2 after ovulation (Day 0). Stages of oocyte maturation and embryo development were determined after ovariectomy at different time points after ovulation. Aglepristone did not prevent ovulation but delayed the resumption of oocyte meiosis and inhibited its progression: first metaphase I (MI) stage was observed at 173 h postovulation and 39% of oocytes reached MII as late as 335 h postovulation in treated females whereas first MI occurred at 76 h and 100% of oocytes were in MII at 109 h postovulation in controls. Aglepristone extended the stay of morphologically normal oocytes within the oviducts: first signs of oocyte degeneration were observed at 335 h in treated versus 100- to 110-h postovulation in control bitches. In inseminated females, aglepristone prevented sperm progression toward the oviducts and fertilization, although motile spermatozoa were observed in the uterine tip flush and within the cranial uterine glands. A proteomic analysis of the tubal fluid from treated and control noninseminated bitches at Day +4 found evidence of 79 differential proteins potentially involved in the oocyte phenotype. In conclusion, P4 plays key roles in postovulatory canine oocyte maturation, aging, and in fertilization.
Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France.
Karine
K
Reynaud
Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France AgroParisTech, Génétique Elevage Reproduction, Paris, France marie.saint-dizier@tours.inra.fr.
Marie
M
Saint-Dizier
Ecole Nationale Vétérinaire d'Alfort, Reproduction, Maisons-Alfort, France INRA, Unité Mixte de Recherche Biologie du Développement et Reproduction, Jouy-en-Josas, France.
Muhammad Zahid
MZ
Tahir
Ecole Nationale Vétérinaire d'Alfort, Reproduction, Maisons-Alfort, France INRA, Unité Mixte de Recherche Biologie du Développement et Reproduction, Jouy-en-Josas, France.
Tiphaine
T
Havard
Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France INRA, Plateforme d'Analyse Intégrative des Biomolécules, Nouzilly, France.
Grégoire
G
Harichaux
Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France INRA, Plateforme d'Analyse Intégrative des Biomolécules, Nouzilly, France.
Valérie
V
Labas
Ecole Nationale Vétérinaire d'Alfort, Reproduction, Maisons-Alfort, France.
Sandra
S
Thoumire
Ecole Nationale Vétérinaire d'Alfort, Reproduction, Maisons-Alfort, France.
Alain
A
Fontbonne
Ecole Nationale Vétérinaire d'Alfort, Reproduction, Maisons-Alfort, France INRA, Unité Mixte de Recherche Biologie du Développement et Reproduction, Jouy-en-Josas, France.
Bénédicte
B
Grimard
Institut National Polytechnique-Ecole Nationale Vétérinaire de Toulouse, Reproduction, Toulouse, France INRA, Unité Mixte de Recherche Interactions Hôte-Pathogènes, Toulouse, France.
Sylvie
S
Chastant-Maillard
D000818:Animals; D004285:Dogs; D047108:Embryonic Development / Q000187:drug effects; D004963:Estrenes / Q000494:pharmacology; D005187:Fallopian Tubes / Q000502:physiology; D005260:Female; D005306:Fertilization / Q000502:physiology*; D008297:Male; D008540:Meiosis / Q000187:drug effects; D008677:Metaphase / Q000187:drug effects; D009865:Oocytes / Q000502:physiology*; D010052:Ovariectomy; D011247:Pregnancy; D011374:Progesterone / Q000037:antagonists & inhibitors / Q000502:physiology*; D020543:Proteome / Q000187:drug effects; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects; D014599:Uterus / Q000187:drug effects
D004963:Estrenes; D020543:Proteome; C419063:aglepristone; D011374:Progesterone
aglepristone; antiprogestin; canine; fertilization; maturation; oocyte; progesterone; spermatozoa