Participation of GABAB Receptors of Parafacial Respiratory Group in the Regulation of Respiration in Rats

Abstract

The respiratory effects of microinjections of baclofen and 2-hydroxysaclofen into the parafacial respiratory group were studied in experiments on rats. It was shown that activation of GABA_B receptors of the parafacial respiratory group suppressed external respiration due to a decrease in the tidal volume and inspiratory flow rate. In parallel, we observed a decrease in the amplitude and an increase in the duration of inspiratory bursts of the diaphragm. Injection of GABA_B receptor blocker into the parafacial respiratory group increased pulmonary ventilation due to an increase in volumetric parameters of the inspiratory phase. This effect was accompanied by prolongation of expiration and lengthening of the intervals between the inspiratory bursts of the diaphragm. These results suggest that GABA_B receptors of the parafacial respiratory group are an important element of the central mechanisms regulating the volumetric respiratory parameters and are involved in the regulation of the phases of the respiratory cycle.