title: Patterns of Apoptosis and Proliferation throughout the Biennial Reproductive Cycle of Viviparous Female Typhlonectes compressicauda (Amphibia, Gymnophiona).
abstract: Typhlonectes compressicaudais an aquatic gymnophionan amphibian living in South America. Its breeding cycle is linked to seasons, characterized by a regular alternation of rainy and dry seasons. During a complex biennial cycle, the female genital tract undergoes a series of alternations of increasing and decreasing, governed by equilibrium of proliferation and apoptotic phenomena. Immunohistochemical methods were used to visualize cell proliferation with the detection of Ki67 antibody, a protein present in proliferative cells; terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and Apostain were performed to detect apoptotic cells on sections of ovaries and oviducts. In ovaries, both phenomena affect the germinal nests and follicles according to the cycle period. In the oviduct, the balance was in favor of proliferation during preparation for reproduction, and in favor of apoptosis when genital ducts regress. Apoptosis and proliferation are narrowly implicated in the remodeling of the genital tract and they are accompanied by the differentiation of tissues according to the phase of the breeding cycle. These variations permit the capture of oocytes at ovulation, always at the same period, and the parturition after 6-7 months of gestation, at a period in which the newborns live with their mother, protected in burrows in the mud. During the intervening year of sexual inactivity, the female reconstitutes body reserves.
authors.affiliation: Laboratory of General Biology, Lyon Catholic University, UMRS 449, University of Lyon, 69288 Lyon Cedex 02, France. mraquet@univ-catholyon.fr.|Laboratory of Reproduction and Comparative Development, Ecole Pratique des Hautes Etudes, Paris Sciences Lettres, 69288 Lyon Cedex 02, France. mraquet@univ-catholyon.fr.
authors.forename: Michel
authors.initials: M
authors.lastname: Raquet
authors.affiliation: Laboratory of General Biology, Lyon Catholic University, UMRS 449, University of Lyon, 69288 Lyon Cedex 02, France. cbrun@univ-catholyon.fr.|Laboratory of Reproduction and Comparative Development, Ecole Pratique des Hautes Etudes, Paris Sciences Lettres, 69288 Lyon Cedex 02, France. cbrun@univ-catholyon.fr.
authors.forename: Claire
authors.initials: C
authors.lastname: Brun
authors.affiliation: Laboratory of General Biology, Lyon Catholic University, UMRS 449, University of Lyon, 69288 Lyon Cedex 02, France. jmexbrayat@univ-catholyon.fr.|Laboratory of Reproduction and Comparative Development, Ecole Pratique des Hautes Etudes, Paris Sciences Lettres, 69288 Lyon Cedex 02, France. jmexbrayat@univ-catholyon.fr.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Exbrayat
mesh_terms: D000663:Amphibians; D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D005260:Female; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D010053:Ovary / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D012098:Reproduction; D012621:Seasons; D052286:Viviparity, Nonmammalian
keywords: Typhlonectes compressicauda; amphibian; apoptosis; gymnophiona; ovary; oviduct; proliferation; sexual cycle