Year-end Sale % OFF 
Abstract
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.
Highlights
The respiratory and cardiovascular systems act in synergy to maintain blood gas homeostasis in animals
Post hoc histological analysis revealed the guillardia theta anion channelrhodopsin 2 (GtACR2) expression was targeted to the gap in the rostrocaudal column of parvalbumin-expressing neurons (Figure 1A; Alheid et al, 2002), dorsal to tyrosine hydroxylase (TH)-expressing A1-C1 neurons, ventral to the caudal tip of the compact part of the nucleus ambiguus, and at the level containing the highest density of neurokinin type 1 receptor (NK1R)-positive neurons (Figure 1B)
We investigated the role played by PreBotC neurons in the respiratory modulation of thoracic sympathetic nerve activity (tSNA) (RespSNA), perfusion pressure (PP) (Traube-Hering waves) and heart rate (HR) (RSA)
Summary
The respiratory and cardiovascular systems act in synergy to maintain blood gas homeostasis in animals Beyond their respective separate roles, these systems are functionally coupled, with oscillations in blood pressure (BP), called Traube-Hering waves, and in heart rate (HR), called respiratory sinus arrhythmia (RSA), that are in phase with the respiratory cycle. This respiratory entrainment of cardiovascular activity is a highly conserved physiological property present in vertebrates, including mammals, fish, amphibians and reptiles (Taylor et al, 2010; Taylor et al, 1999), and was recently found in the early air-breathing primitive lungfish (Monteiro et al, 2018).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
