['INBIFO', 'Institut', 'far', 'biologische', 'Forschung', '-', 'KéIn', 'DOCUMENTATION', 'P', '0500/5061', 'MNO69RA24', '6155', 'PAGE', '4-4', ' ', 'recurrent', 'nerve', 'of', 'the', 'vagus', 'nerve', 'in', 'the', 'larynx.', 'A', 'few', 'reflex', 'responses', 'are', 'mediated', 'by', 'stimulation', 'of', 'free', 'nerve', 'endings', 'in', 'the', 'inner', 'oral', 'cavity', 'and', 'tongue', 'as', 'well', 'as', 'by', 'those', 'of', 'the', 'cornea.', 'All', 'mentioned', 'receptors', 'belong', 'to', 'the', '"common', 'chemical', 'sense"', 'in', 'mammals', 'and', 'in', 'general', 'can', 'be', 'stimulated', 'by', 'the', 'same', 'chemical.', 'Sensory', 'irritation', 'is', 'associated', 'with', 'a', 'painful', 'burning', 'sensation', 'and', 'a', 'wide', 'variety', 'of', 'reflex', 'reactions.', 'The', 'ist', 'to', 'be', 'observed', 'is', 'a', 'decrease', 'in', 'respiratory', 'rate', 'which', 'limits', 'or', 'prevents', 'the', 'material', 'from', 'reaching', 'the', 'lower', 'respiratory', 'tract.', 'The', 'reaction', 'is', 'caused', 'by', 'a', 'lengthening', 'of', 'the', 'respiratory', 'phase', 'and', 'is', 'due', 'to', 'an', 'inhibition', 'of', 'the', 'phrenic', 'nerve', 'and', 'the', 'intercostal', 'nerves', 'which', 'innervate', 'the', 'diaphragm', 'and', 'the', 'intercostal', 'muscles', 'respec-', 'tively.', 'Other', 'reactions', 'also', 'occur,', 'mostly', 'secondary', 'to', 'the', 'decrease', 'in', 'respiratory', 'rate', 'which', 'compensate', 'for', 'the', 'lower', 'pulmonary', 'ventilation', 'during', 'the', 'exposure', 'to', 'sensory', 'irritants.', 'These', 'compensating', 'reactions', 'are', 'started', 'by', 'influencing', 'the', 'sympathetic', 'and', 'parasympathetic', 'nervous', 'system.', 'The', 'physiologic', 'reactions', 'mediated', 'by', 'the', 'sympathetic', 'nervous', 'systems', 'are', '(1)', 'a', 'vasoconstriction', 'of', 'the', 'blood', 'vessels', 'of', 'skin,', 'muscles,', 'viscera', 'and', 'kidney', 'with', 'a', 'rise', 'in', 'arterial', 'blood', 'pressure,', '(2)', 'a', 'secretion', 'of', 'catecholamines', 'by', 'the', 'adrenal', 'medulla', 'and', '(3)', 'a', 'decrease', 'in', 'coronary', 'blood', 'flow.', 'The', 'physiologic', 'reactions', 'mediated', 'by', 'the', 'parasympathetic', 'nervous', 'system', 'are', '(1)', 'a', 'bradycardia,', '(2)', 'a', 'bronchoconstriction,', '(3)', 'a', 'spasm', 'of', 'the', 'larynx', 'and', '(4)', 'a', 'coughing', 'response.', 'The', 'bradycardia', 'results', 'in', 'a', 'decrease', 'in', 'cardiac', 'output', 'which', 'affects', 'other', 'organs', 'such', 'as', 'lung', 'or', 'kidney.', 'In', 'both', 'organs', 'the', 'blood', 'flow', 'is', 'reduced.', 'In', 'case', 'of', 'the', 'kidney', 'this', 'reduced', '|', 'blood', 'flow', 'causes', 'a', 'decrease', 'in', 'clearance.', 'In', 'the', 'nose', 'sensory', 'irritants', 'trigger', 'a', 'sneezing', 'response', 'and', 'sometimes', 'a', 'closure', 'of', 'the', 'nares', 'whereas', 'in', 'the', 'eyes', 'they', 'cause', 'lacrimation.', 'In', 'addition:', 'to', 'possible', 'edema', 'in', 'the', 'respiratory', 'tract,', 'the', 'closure', 'of', 'the,', 'nares,', 'the', 'spasm', 'of', 'the', 'larynx', 'and', 'the', 'bronchoconstriction', 'are:', 'responsible', 'for', 'the', 'increase', 'in', 'airflow', 'resistance', 'in', 'the', "respira-'", 'tory', 'tract.', '3285', '802Zersosz']