Participation of purinergic receptors of nucleus of the solitary tract in the cardiorespiratory responses induced by hypoxia

• Grant number: 13/25056-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2014
• End date: February 28, 2015
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Patricia Maria de Paula
• Grantee: Naira Marques
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The nucleus of solitary tract (NTS) is located in the brainstem, the first area in the central nervous system that receives projections from the peripheral baroreceptors and chemoreceptors. Studies demonstrated that L-glutamate and more recently the ATP are the neurotransmitters involved in the peripheral chemorreflex in the NTS. The hypoxia is a well-known stimulus that decreases the partial pressure of oxygen in the arterial blood, promoting an increase in discharges of the peripheral chemoreceptors that stimulate the many central areas for example the NTS, resulting in a series of compensatory responses like an increase on ventilation and hypothermia. Recent studies have showed that purinergic neurotransmitters (ATP e Adenosine) participate in central cardiorespiratory control, acting specifically in the NTS. Furthermore, preliminary results from our laboratory showed that blockade of purinergic receptors, by the injection of suramin (non-selective purinergic receptors antagonist) in the NTS attenuates the hyperventilation response induced by hypoxia. This way it is possible that the purinergic receptors in the NTS participate in the cardiorespiratory responses induced by hypoxia. Thus in the present study, we investigated the involvement of P2Y purinergic receptors in the NTS, through the injection of P2Y purinergic receptor antagonist (MRS 2179) and agonist (MRS 2365) and compare these effects with the P2X purinergic receptors agonist ±,²-metileneATP in the NTS on cardiorespiratory responses induced by hypoxia in awake rats. (AU)