title: Melatonin deprival modifies follicular and corpus luteal growth dynamics in a sheep model.
abstract: This study assessed the effect of melatonin deprival on ovarian status and function in sheep. Experimental procedures were carried out within two consecutive breeding seasons. Animals were divided into two groups: pinealectomised (n=6) and sham-operated (n=6). The completeness of the pineal gland removal was confirmed by the plasma concentration of melatonin. Ovarian status was monitored by ovarian ultrasonography for 1 year to study reproductive seasonality. Follicular and corpus luteal growth dynamics were assessed during an induced oestrous cycle. As the effects of melatonin on the ovary may also be mediated by its antioxidant properties, plasma Trolox equivalent antioxidant capacity (TEAC) was determined monthly for 1 year. Pinealectomy significantly extended the breeding season (310±24.7 vs 217.5±24.7 days in controls; P<0.05). Both pinealectomised and sham-operated ewes showed a well-defined wave-like pattern of follicle dynamics; however, melatonin deficiency caused fewer waves during the oestrous cycle (4.3±0.2 vs 5.2±0.2; P<0.05), because waves were 1 day longer when compared with the controls (7.2±0.3 vs 6.1±0.3; P<0.05). The mean area of the corpora lutea (105.4±5.9 vs 65.4±5.9 mm(2); P<0.05) and plasma progesterone levels (7.1±0.7 vs 4.9±0.6 ng/ml; P<0.05) were significantly higher in sham-operated ewes compared with pinealectomised ewes. In addition, TEAC values were significantly lower in pinealectomised ewes compared with control ones. These data suggest that melatonin, besides exerting its well-known role in the synchronisation of seasonal reproductive fluctuations, influences the growth pattern of the follicles and the steroidogenic capacity of the corpus luteum.
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Manca
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Manunta
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Antonio
authors.initials: A
authors.lastname: Spezzigu
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Laura
authors.initials: L
authors.lastname: Torres-Rovira
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Antonio
authors.initials: A
authors.lastname: Gonzalez-Bulnes
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Valeria
authors.initials: V
authors.lastname: Pasciu
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Piu
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Giovanni G
authors.initials: GG
authors.lastname: Leoni
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Sara
authors.initials: S
authors.lastname: Succu
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, FranceDepartment of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Chesneau
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Naitana
authors.affiliation: Department of Veterinary MedicineUniversity of Sassari, Via Vienna 2, 07100 Sassari, ItalyEmbryo SardegnaTechnology, Reproduction, and Fertility, 07034 Perfugas, Località Suiles (SS), ItalyDepartment of Animal ReproductionINIA, Avda. Puerta de Hierro s/n, 28040 Madrid, SpainInstitut National de la Recherche Agronomique (INRA)UMR85, F-37380 Nouzilly, FranceCNRSUMR 7247, Université François Rabelais de Tours, F-37041 Tours, France berling@uniss.it.
authors.forename: Fiammetta
authors.initials: F
authors.lastname: Berlinguer
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D003338:Corpus Luteum / Q000000981:diagnostic imaging / Q000378:metabolism*; D030762:Estrous Cycle / Q000378:metabolism*; D005260:Female; D008550:Melatonin / Q000097:blood / Q000172:deficiency*; D023421:Models, Animal; D006080:Ovarian Follicle / Q000000981:diagnostic imaging / Q000378:metabolism*; D010870:Pineal Gland / Q000378:metabolism* / Q000601:surgery; D011374:Progesterone / Q000097:blood; D012098:Reproduction; D012621:Seasons; D012756:Sheep; D013997:Time Factors; D014463:Ultrasonography
chemical_list: D000975:Antioxidants; D011374:Progesterone; D008550:Melatonin