1. Extracellular Adenosine 5'-Triphosphate in Obstructive Airway Diseases
Amir Pelleg, PhD, Edward S. Schulman, MD, Peter J. Barnes, DM, Master FCCP 
CHEST 
Volume 150, Issue 4, Pages (October 2016)
DOI: /j.chest
Copyright © 2016 American College of Chest Physicians Terms and Conditions

2. Figure 1
Multiunit recordings demonstrating that ATP but not capsaicin activates canine pulmonary rapidly adapting receptors (RARs) in vivo. Arrowheads show AP of Aδ fibers with RARs. Smaller amplitude AP: C-fibers’ discharge. Note the cardiac bradycardia and the associated drop in BP due to a concurrent cardio-cardiac central vagal reflex.64 AP = action potentials; ATP = adenosine 5′-triphosphate; ECG II = lead II electrocardiogram; IPS = impulses per second; TP = tracheal pressure.
CHEST  , DOI: ( /j.chest )
Copyright © 2016 American College of Chest Physicians Terms and Conditions

3. Figure 2
Effect of bilateral cervical vagotomy on ATP-induced bronchoconstriction in the canine lungs in vivo. Radiograph shows control (left panel); following injection of ATP (10 μmol/kg into the right atrium [middle panel]); and following injection of ATP in the presence of bilateral cervical vagatomy (right panel). I-III represent generations of the airways. Arrows denote marked change in airway diameter. In the presence of bilateral vagotomy, ATP did not cause any bronchoconstriction; moreover, the noticeable bronchodilation indicates constitutive vagal tone under baseline conditions, which was eliminated by the vagatomy. See Figure 1 legend for expansion of abbreviation.
CHEST  , DOI: ( /j.chest )
Copyright © 2016 American College of Chest Physicians Terms and Conditions

4. Figure 3
Schematic diagram summarizing the sources of extracellular ATP and its effects under physiologic and pathophysiologic conditions in the lungs. P1R = P1 purinergic receptors (adenosine receptors); P2R = P2 purinergic receptors (ATP receptors, which can be activated by other adenine nucleotides). See Figure 1 legend for expansion of other abbreviation.
CHEST  , DOI: ( /j.chest )
Copyright © 2016 American College of Chest Physicians Terms and Conditions