Participation of orexinergic neurotransmission in the cardio-respiratory responses to hypercarbia and hypoxia of toads

• Grant number: 10/16793-1
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2011
• End date: December 31, 2012
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Luciane Helena Gargaglioni Batalhão
• Grantee: Luciane Helena Gargaglioni Batalhão
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Hypocretin or orexin plays an important role on the cardio-respiratory control in mammals, but no study examined this possibility in non-mammalian vertebrate. Thus, the present project will investigate the role of orexinergic neurotransmission of toads (Rhinella schneideri) in the respiratory and cardiovascular responses during normocapnia normoxic, hypoxia and hypercapnia. To this end, we will perform c-fos immunocytochemistry to examine whether orexinergic neurons are activated in situations of hypercarbia (5% CO2) and hypoxia (5% O2). Additionally, we will inject agonists (orexin A) and antagonist of orexin 1 receptor (SB-334867) or vehicle in the ventricle, to compare the cardio-respiratory responses to normocapnia normoxia, hypoxia and hypercapnia, before and after microinjection. (AU)