The Corpus Luteum of the Dog: Source and Target of Steroid Hormones?

Autor(es)

Papa, P. C. ^[1] ; Hoffmann, B. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Setor Anat, Dept Cirurgia, Fac Med Vet & Zootecnia, BR-05508270 Sao Paulo - Brazil

^[2] Univ Giessen, Fak Vet Med, Klin Geburtshilfe Gynaekol & Androl Gross & Klein, Giessen - Germany

• Tipo de documento: Artigo de Revisão
• Fonte: REPRODUCTION IN DOMESTIC ANIMALS; v. 46, n. 4, p. 750-756, AUG 2011.
• Citações Web of Science: 13

Resumo

Aim of this paper is to review our present understanding on the endocrine control of luteal function in the bitch and to add some new data generated in our laboratories in support of the hypothesis of a paracrine/autocrine role of corpus luteum (CL) derived steroid hormones. Luteal lifespan in non-pregnant dogs often exceeds that of pregnant dogs, where luteal regression terminates in a rapid luteolysis, immediately prior to parturition. In non-pregnant dogs, luteal regression occurs independently of a uterine luteolysin and in spite of increased gonadotropic support during the last third of dioestrus. The CL is the only source of progesterone (P(4)) maintaining pregnancy, and they have the capacity to synthesize oestrogens as substantiated by expression of the CYP19 (aromatase) gene observed in this study. Our data demonstrated that lutein and non-lutein cells of the canine CL express in a rather constant manner the progesterone receptor (PR) and the oestrogen receptor, classifying them as targets for an autocrine/paracrine activity of CL-derived steroids. Therefore, a functional role of P4 within a positive loop feedback system, including StAR and 3 beta-hydroxysteroid dehydrogenase, has been postulated. (AU)

• Processo FAPESP: 02/07392-7 - Expressão do VEGF e bFGF na placenta bovina e seus efeitos sobre a produção de hormônios esteróides neste órgão
• Beneficiário: Paula de Carvalho Papa Keohane
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores