The presence of neurotrophins and their specific receptors in adult and developing Japanese quail ovaries

The presence of neurotrophins and their specific receptors in adult and developing Japanese quail ovaries Nechita E-L, Arcamone N, Maruccio L, Solcan C, Cotea C Nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) are members of neurotrophins family, which are involved in growth, maintaining, differentiation and survival of neurons in the central and peripheral nervous system. The activity of these neurotrophins is elicited in systems other than nervous, such as reproductive and endocrine systems. In mammals, neurotrophins and their receptors TrkA, TrkB, TrkC play a critical role in oogenesis and folliculogenesis, promoting the follicular development and oo-cyte maturation, also during early embryonic development. In this study we report the presence of NGF, BDNF, NT-3 and their specific receptors in adult and embryonic quail gonads. The investigations were con-ducted on embryonic stages from 4th to 17th day of incubation and on adult laying quail ovaries. Immunohisto-chemical Envision technique was used. The immunoreactivity (ir) was observed from 6th day of embryonic de-velopment. Neurotrophins and their receptors were differently distributed in cortical and medullary areas. The localization of NGF, NT3 and Trk receptors-ir was differently observed in cytoplasm of oocytes, follicular cells and stromal cells, both in adult and embryonic quail ovaries from the 9th day of incubation, while BDNF ir was observed only in adult. The results obtained confirm the involvement of neurotrophins during the development of gonads in quails, as well as in mammals. Furthermore, the occurrence of neurotrophins and the receptors could provide new insights on their possible paracrine and/or autocrine mode of action in quail ovary during development and folliculogenesis.