Episodic stimulation of central chemoreceptor neurons elicits disordered breathing and autonomic dysfunction in volume overload heart failure.

Episodic stimulation of central chemoreceptor neurons elicits disordered breathing and autonomic dysfunction in volume overload heart failure. Am J Physiol Lung Cell Mol Physiol. 2019 Oct 16;: Authors: Diaz HS, Andrade DC, Toledo C, Pereyra KV, Schwarz KG, Díaz-Jara E, Lucero C, Arce-Alvarez A, Schultz HD, Silva JN, Takakura AC, Moreira TS, Marcus NJ, Del Rio R Abstract Enhanced central chemoreflex (CC) gain is observed in volume overload heart failure (HF) and is correlated with autonomic dysfunction and breathing disorders. The aim of this study was to determine the role of the CC in the development of respiratory and autonomic dysfunction in HF. Volume overload was surgically created to induced HF in male Sprague-Dawley rats. Radiotelemetry transmitters were implanted for continuous monitoring of blood pressure and heart rate. Upon recovery from surgery, conscious unrestrained rats were exposed to episodic hypercapnic stimulation (EHS, 10 cycles/5 min, FiCO27%) in a whole-body plethysmograph for recording of cardiorespiratory function. To determine the contribution of CC to cardiorespiratory variables, selective ablation of chemoreceptor neurons within the retrotrapezoid nucleus (RTN) was performed via injection of saporin toxin-conjugated to substance P (SSP-SAP). Vehicle treated rats (HF+Veh and Sham+Veh) were used as controls for SSP-SAP experiments. Sixty minutes post-EHS, minute ventilation was depressed in sham animals rela...
Source: American Journal of Physiology. Lung Cellular and Molecular Physiology - Category: Cytology Authors: Tags: Am J Physiol Lung Cell Mol Physiol Source Type: research