Cardiopulmonary function and dysregulated cardiopulmonary reflexes following acute oleoresin capsicum exposure in rats

Cardiopulmonary functions such as respiratory depression, severe irritation, inflamed respiratory tract, hyperventilation and, tachycardia are the most affected ones when it comes to the riot control agent oleoresin capsicum (OC) exposure. However, no studies have been done to elucidate the mechanism underlying deterioration of the combined cardiopulmonary functions. Parameters such as acute respiratory, cardiac, parameters and ultrasonography (USG) measurements were investigated in an in vivo setup using Wistar rats at 1 h and 24 h post inhalation exposure to 2%, 6% and 10% OC, whereas, cell migration in rat peritoneal mast cells (RPMCs), metabolomics and eosinophil peroxidase (EPO) activity in bronchoalveolar lavage fluid (BALF) were investigated in an in vitro setup. Results obtained from electrophysiological recording indicated that OC exposure produces apnea and decrease in mean arterial pressure (MAP) was obtained from hemodynamic parameters whereas cardiac parameters assessment revealed increase in the level of cardiac output (CO) and decrease in stroke volume (SV) with recovery towards the post-exposure period. A decrease in the percentage area of certain fatty acid pathway metabolites in BALF appropriately linked the lung injury following OC exposure which was further cemented by increasing concentration of EPO. Histopathology and SEM also proved to be favorable techniques for the detection of OC induced physiological cardiac and pulmonary modifications respectively. Furthermore, Boyden chamber experiment established the chemoattractant property of OC. It may be concluded from the above studies that these newly reported facets may be utilized pharmacologically to mitigate cardiopulmonary adverse effects owing to OC exposure.

Keywords: Biodistribution; Cardiopulmonary; Chemotactic; Oleoresin Capsicum; Riot Control; Ultrasonography.