Brain distribution of immunoreactive neurons and fibers expressing GnIH in pejerrey, Odontesthes bonariensis.

GUSTAVO M. SOMOZA; MARÍA RITA PÉREZ; PAULA GABRIELA VISSIO; ANA MARÍA PAHÍ-ROSERO; GABRIELA CARINA LÓPEZ

Ciudad Autonoma de Buenos Aires

Congreso; REUNIÓN CONJUNTA DE SOCIEDADES DE BIOCIENCIAS; 2018

SOCIEDAD ARGENTINA DE BIOLOGÍA (SAB)

Gonadotrophin-inhibitory hormone (GnIH) is a RFamide peptide,originally characterized in the japanese quail as an inhibitorof gonadotropins, changing the classical view of the regulation ofvertebrate reproduction. Later, it was also found in others vertebratespecies, with similar function. However, the effects in fish remaincontroversial. In this context, as a first step, the objective of this workwas characterized the neuroanatomic distribution of GnIH neuronsand fibers in the brain of adult pejerrey by immunohistochemistry.Our results showed that neuronal somata with immunoreactivity toGnIH (ir-GnIH) were localized at the olfactory bulbs, the junction ofthe olfactory bulbs and telencephalon (Terminal Nerve Ganglion orNucleus Olfacto Retinalis) and the Nucleus Posterioris Periventricularis(NPPv). This distribution was similar to that reported in otherteleost fish species. Moreover, some isolated neuronal somata weredetected in the Nucleus Paraventricularis Posterioris (NPP) in thepreoptic area (POA). While ir-GnIH fibres were present in all brainareas examined, and also at the pituitary gland. In addition, doublelabelling with GnIH and GnRH I (also known as pjGnRH) antiserawas performed, in order to analyze a possible relationship betweenGnIH and the hypophysiotropic GnRH variant of this species. Indouble labelling immunocytochemistry, ir-GnIH fibers were localizedvery close to ir-GnRH neurons in the preoptic area, suggesting thatboth neurons could interact. This is the report on the GnIH distributionin the brain of pejerrey and its relation with GnRH.