Sympathetic modulation of biochemical and physiological response to immune degranulation in canine bronchial airways in vivo. j Clin. Invest. 75

The effect of sympathetic stimulation on bronchial smooth muscle contractile response after mast cell degranulation with Ascaris suum antigen was studied in 36 natively allergic dogs in situ. Bronchial smooth muscle response was measured isometrically in a single right middle lobe bronchus. A dose of antigen causing maximal release of mediator was administered to the bronchus through the bronchial arterial circulation. Serial plasma histamine concentrations were determined at 15-s intervals after intra-arterial (i.a.) administration of antigen. Samples of blood were obtained simultaneously from right heart and femoral artery, and arteriovenous difference (AVd) in histamine concentration across the bronchus was determined during mast cell degranulation. In nine dogs showing bronchial mast cell degranulation to antigen challenge, bronchial smoot