Department of Physiology, University of Melbourne, Victoria, Australia; Institut de Neurobiologie de la Méditerranée, INMED UMR1249, INSERM, Aix-Marseille Université, Marseille, France
Angela A Connelly
Department of Physiology, University of Melbourne, Victoria, Australia
Jaspreet K Bassi
Department of Physiology, University of Melbourne, Victoria, Australia
Mariana R Melo
Department of Physiology, University of Melbourne, Victoria, Australia
Sheng Le
Faculty of Medicine & Health Sciences, Macquarie University, NSW, Australia
Jessica Kamar
Department of Physiology, University of Melbourne, Victoria, Australia
Natasha N Kumar
Department of Pharmacology, School of Medical Sciences, University of New South Wales, NSW, Australia
Department of Physiology, University of Melbourne, Victoria, Australia; Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia
Heart rate and blood pressure oscillate in phase with respiratory activity. A component of these oscillations is generated centrally, with respiratory neurons entraining the activity of pre-sympathetic and parasympathetic cardiovascular neurons. Using a combination of optogenetic inhibition and excitation in vivo and in situ in rats, as well as neuronal tracing, we demonstrate that preBötzinger Complex (preBötC) neurons, which form the kernel for inspiratory rhythm generation, directly modulate cardiovascular activity. Specifically, inhibitory preBötC neurons modulate cardiac parasympathetic neuron activity whilst excitatory preBötC neurons modulate sympathetic vasomotor neuron activity, generating heart rate and blood pressure oscillations in phase with respiration. Our data reveal yet more functions entrained to the activity of the preBötC, with a role in generating cardiorespiratory oscillations. The findings have implications for cardiovascular pathologies, such as hypertension and heart failure, where respiratory entrainment of heart rate is diminished and respiratory entrainment of blood pressure exaggerated.
