Influence of insulin-like growth factor-binding proteins-2 and -3 in follicular cysts in bovine with cystic ovarian disease

RODRIGUEZ FM; SALVETTI NR; PANZANI CG; BARBEITO CG; ORTEGA HH; REY F

ANIMAL REPRODUCTION SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2011 vol. 128 p. 1 - 10

0378-4320

Ovarian cysts are one of the major causes of infertility in dairy cows. Their development is associated with an endocrine imbalance in the hypothalamo-hypophyseal-gonadal axis in which endocrine factors, such as growth factors, participate in follicular growth and differentiation and in the secretion of ovarian hormones. Growth factors such as those belonging to the Insulin-like growth factor family are also essential local regulators of ovarian follicle development and functionality and in some cases their actions are mediated by binding protein activity. The aim of the present study was to analyse the expression of IGFBP-2 and IGFBP-3 in developing follicles of normal cycling animals and with spontaneous and induced cystic ovarian disease (COD) to determine IGF bioavailability. The mRNA of IGFBP-2 and IGFBP-3 in follicular walls was quantified by reverse transcription-polymerase chain reaction (RT-PCR) and in-situ hybridisation. Protein expression was analysed by immunohistochemistry. The results demonstrated reduced levels of mRNA of both IGFBPs in the granulosa cells of ovarian follicles of animals with COD (p<0.05). The present study suggests that the IGF system or imbalances between IGFs and IGFBPs may be involved in bovine COD.