Role played by P2X and P2Y receptors in evoking the muscle chemoreflex

• Published in: Journal of applied physiology (1985) Vol. 104; no. 2; pp. 538 - 541
• Main Authors: Hayes, Shawn G, McCord, Jennifer L, Kaufman, Marc P
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.02.2008; American Physiological Society
• Subjects: Adenosine triphosphatase; Adenosine Triphosphate - administration & dosage; Adenosine Triphosphate - analogs & derivatives; Adenosine Triphosphate - metabolism; Animals; Baroreflex - drug effects; Biological and medical sciences; Blood Pressure; Capsaicin - administration & dosage; Cats; Chemoreceptor Cells - drug effects; Chemoreceptor Cells - metabolism; Exercise; Fundamental and applied biological sciences. Psychology; Heart Rate; Injections, Intra-Arterial; Male; Muscle Contraction; Muscle Denervation; Muscle, Skeletal - drug effects; Muscle, Skeletal - innervation; Muscle, Skeletal - metabolism; Nervous system; Phrenic Nerve - physiology; Physical Exertion - physiology; Pulmonary Ventilation; Purinergic P2 Receptor Agonists; Receptors, Purinergic P2 - metabolism; Sciatic Nerve - surgery; T cell receptors; Tissues; Uridine Triphosphate - administration & dosage; Uridine Triphosphate - metabolism; Physical exercise; Fissipedia; Carnivora; Chemoreflex; exercise; neural control of circulation; Striated muscle; phrenic nerve activity; Vertebrata; Mammalia; P2Y purinergic receptor; cats; Phrenic nerve; Autonomic nervous system; Cat; P2X purinergic receptor; groups III and IV muscle afferents
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00929.2007

Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania Submitted 31 August 2007 ; accepted in final form 30 November 2007 ABSTRACT The role played by purinergic 2Y receptors in evoking the muscle chemoreflex is not well defined. To shed light on this issue, we compared the pressor responses with popliteal arterial injection of UTP (1 mg/kg), a selective P2Y agonist, with those to popliteal arterial injection of ATP (1 mg/kg), a P2X and P2Y agonist, and to ,β-methylene ATP (50 µg/kg), a selective P2X1 and P2X3 agonist, in decerebrate unanesthetized cats. We found that injection of ATP and ,β-methylene ATP increased mean arterial pressure by 19 ± 2 and 15 ± 4 mmHg, whereas UTP had no affect on arterial pressure. In addition, the pressor responses to injection of ATP and ,β-methylene ATP were abolished by section of the sciatic nerve, demonstrating that they were reflex in origin. We conclude that P2Y receptors on thin fiber muscle afferents play no role in evoking the muscle chemoreflex. exercise; groups III and IV muscle afferents; cats; autonomic nervous system; neural control of circulation; phrenic nerve activity Address for reprint requests and other correspondence: S. G. Hayes, Heart and Vascular Institute H047, Penn State College of Medicine, 500 Univ. Dr., Hershey, PA 17033 (e-mail: shayes1{at}hmc.psu.edu )