Laboratory of Autonomic and Respiratory Control Leni G.H. Bonagamba
Role of neuron-glia interaction on
the synaptic transmission of chemoreflex
Short-term sustained hypoxia [(SH) 24 hours, pO2 10%] produces cardiovascular and respiratory changes due to peripheral chemoreflex activation. Moreover, SH also produces alterations in structural and functional integrity of tripartite synapse (presynaptic membrane, postsynaptic membrane and their intimate association with surrounding astrocytes), consequently affecting the synaptic transmission. Using whole-cell patch clamp technique, we evaluate the effect of SH on tripartite synapse at the Nucleus Tractus Solitarius (NTS), the first synaptic station of peripheral chemoreflex in the central nervous system.
Role of Astrocytes on possible changes in the autonomic and respiratory responses to sustained hypoxia in mice
The main purpose of this project is to characterize the cardiovascular and respiratoryalterations in mice submitted to the sustained hypoxia protocol [(SH) - 24 hs - FiO2 = 0.1). In this context, we are using the in situ Working Heart–Brainstem Preparation (WHBP), to test the hypothesis that glial cells/astrocytes participate in the modulation of neural circuits in the ventral medulla and, consequently, in the sympathetic and respiratory changes in response to sustained hypoxia.
Role of astrocytes glutamate transporters in the modulation
of excitatory synaptic transmission in NTS neurons of mice
submitted to sustained hypoxia
Sustained hypoxia (SH - 24 h - FiO 2 = 0.1) increases the excitatory transmission and reduces astrocytic modulation in the NTS. Considering that the concentration of L-glutamate in the synaptic cleft is regulated by the activity of astrocytic transporters GLT-1 and GLAST, in this project we are evaluating the role of L-glutamate transporters (GLAST and GLT-1) in the enhancement of excitatory transmission in NTS neurons after SH. For this purpose we are using the whole cell patch-clamp technique in brainstem slices.