RT Journal Article
T1 Impact of the glutamatergic neurotransmission within the A5 region on the cardiorespiratory response evoked from the midbrain dlPAG
A1 González-García, Marta
A1 Carrillo-Franco, Laura
A1 Peinado-Aragonés, Carlos Antonio
A1 Díaz-Casares, Amelia
A1 Gago-Calderón, Belén
A1 López-González, Manuel Víctor
A1 Dawid-Milner, Marc Stefan
K1 Transmisión nerviosa
K1 Sistema cardiovascular
K1 Aparato respiratorio
AB Stimulation of the dorsolateral periaqueductal grey matter (dlPAG) in rats evokes an active defensive behaviour together with a cardiorespiratory response characterised by tachypnoea, tachycardia and hypertension. The dlPAG neurons involved in these responses are excitatory, presumably glutamatergic, due to the presence of vesicular glutamate transporter VGLUT2 within their axon terminals. Previously, our group described a functional interaction between dlPAG and the pontine A5 region. Accordingly, in the present work, in order to characterize the role of glutamate within this interaction, experiments were carried out in spontaneously breathing anaesthetized rats (sodium pentobarbitone 60 mg/kg i.p., suplemented with 20 mg/kg i.p.). The cardiorespiratory response evoked by electrical stimulation of the dlPAG (1 ms pulses, 20–50 μA, given at 100 Hz, during 5 s) was analysed before and after the microinjection, within the A5 region, of either kynurenic acid (non-specific glutamate receptor antagonist; 5–10 nmol), DAP-5 (NMDA antagonist; 1 pmol), CNQX (non-NMDA antagonist; 1 pmol) or MCPG (metabotropic antagonist; 0,1 nmol). Kynurenic acid decreased the intensity of both the tachypnoea (p < 0,001) and tachycardia (p < 0,001) induced by dl-PAG stimulation. Blockade of no-NMDA receptors reduced the increase of respiratory frequency, heart rate and pressor response to dl-PAG stimulation (p < 0,01, p < 0,001, p < 0,05 respectively). Blockade of either NMDA or metabotropic receptors reduced the dlPAG-evoked tachycardia and pressor response (p < 0,01; p < 0,05 respectively). These results suggest a neuromodulatory role for A5 region via glutamate neurotransmission of the dlPAG-evoked cardiorespiratory response, confirming the role of the ventrolateral pons in the neuronal circuits involved in respiratory and heart rate control.
PB Springer Nature
YR 2022
FD 2022-12-22
LK https://hdl.handle.net/10630/26459
UL https://hdl.handle.net/10630/26459
LA eng
NO González-García, M. A. R. T. A., Carrillo-Franco, L. A. U. R. A., Peinado-Aragonés, C. A., Díaz-Casares, A. M. E. L. I. A., Gago, B. E. L. É. N., López-González, M. V., & Dawid-Milner, M. S. (2023). Impact of the glutamatergic neurotransmission within the A5 region on the cardiorespiratory response evoked from the midbrain dlPAG. Pflügers Archiv-European Journal of Physiology, 475(4), 505-516.
NO Funding for open access publishing: Universidad Málaga/CBUA   // The study was supported by a program grant Junta de Andalucía, Group nº CTS-156, Spain.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 21 ene 2026