P2X2/3 and P2X3 receptors contribute to the metaboreceptor component of the exercise pressor reflex

Jennifer L. McCord, Hirotsugu Tsuchimochi, Marc Kaufman

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

The exercise pressor reflex is due to activation of thin fiber afferents within contracting muscle. These afferents are in part stimulated by ATP activation of purinergic 2X (P2X) receptors during contraction. Which of the P2X receptors contribute to the reflex is unknown; however, P2X2/3 and P2X3 receptor subtypes are good candidates because they are located on thin fiber afferents and are involved in sensory neurotransmission. To determine if P2X2/3 and P2X3 receptors evoke the metabolic component of the exercise pressor reflex, we examined the effect of two P2X2/3 and P2X3 antagonists, A-317491 (10 mg/kg) and RO-3 (10 mg/kg), on the pressor response to injections of α,β-methylene ATP (α,β-MeATP; 50 μg/kg), freely perfused static contraction, contraction of the triceps surae muscles while the circulation was occluded, and postcontraction circulatory occlusion in decerebrate cats. We found that the antagonists reduced the pressor response to α,β- MeATP injection (beforeΔ20 ± 3 mmHg; drugΔ11 ± 3 mmHg; P < 0.05), suggesting the antagonists were effective in blocking P2X2/3 and P2X3 receptors. P2X2/3 and P2X3 receptor blockade reduced the pressor response to freely perfused contraction (beforeΔ33 ± 5 mmHg; drugΔ15 ± 5 mmHg; P < 0.05), contraction with the circulation occluded (beforeΔ52 ± 7 mmHg; drugΔ20 ± 4 mmHg; P < 0.05), and during postcontraction circulatory occlusion (beforeΔ15 ± 1 mmHg; drug Δ 5 ± 1 mmHg; P < 0.05). Our findings suggest that P2X2/3 and P2X3 receptors contribute to the metabolic component of the exercise pressor reflex in decerebrate cats.

Original languageEnglish (US)
Pages (from-to)1416-1423
Number of pages8
JournalJournal of Applied Physiology
Volume109
Issue number5
DOIs
StatePublished - Nov 1 2010

Fingerprint

Purinergic P2X2 Receptors
Purinergic P2X3 Receptors
Reflex
Purinergic Receptors
Cats
Adenosine Triphosphate
Muscles
Injections
Synaptic Transmission
Pharmaceutical Preparations

All Science Journal Classification (ASJC) codes

  • Physiology
  • Physiology (medical)

Cite this

@article{0fecc2d412b840e68a3f01bf3ae2d246,
title = "P2X2/3 and P2X3 receptors contribute to the metaboreceptor component of the exercise pressor reflex",
abstract = "The exercise pressor reflex is due to activation of thin fiber afferents within contracting muscle. These afferents are in part stimulated by ATP activation of purinergic 2X (P2X) receptors during contraction. Which of the P2X receptors contribute to the reflex is unknown; however, P2X2/3 and P2X3 receptor subtypes are good candidates because they are located on thin fiber afferents and are involved in sensory neurotransmission. To determine if P2X2/3 and P2X3 receptors evoke the metabolic component of the exercise pressor reflex, we examined the effect of two P2X2/3 and P2X3 antagonists, A-317491 (10 mg/kg) and RO-3 (10 mg/kg), on the pressor response to injections of α,β-methylene ATP (α,β-MeATP; 50 μg/kg), freely perfused static contraction, contraction of the triceps surae muscles while the circulation was occluded, and postcontraction circulatory occlusion in decerebrate cats. We found that the antagonists reduced the pressor response to α,β- MeATP injection (beforeΔ20 ± 3 mmHg; drugΔ11 ± 3 mmHg; P < 0.05), suggesting the antagonists were effective in blocking P2X2/3 and P2X3 receptors. P2X2/3 and P2X3 receptor blockade reduced the pressor response to freely perfused contraction (beforeΔ33 ± 5 mmHg; drugΔ15 ± 5 mmHg; P < 0.05), contraction with the circulation occluded (beforeΔ52 ± 7 mmHg; drugΔ20 ± 4 mmHg; P < 0.05), and during postcontraction circulatory occlusion (beforeΔ15 ± 1 mmHg; drug Δ 5 ± 1 mmHg; P < 0.05). Our findings suggest that P2X2/3 and P2X3 receptors contribute to the metabolic component of the exercise pressor reflex in decerebrate cats.",
author = "McCord, {Jennifer L.} and Hirotsugu Tsuchimochi and Marc Kaufman",
year = "2010",
month = "11",
day = "1",
doi = "10.1152/japplphysiol.00774.2010",
language = "English (US)",
volume = "109",
pages = "1416--1423",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "5",

}

P2X2/3 and P2X3 receptors contribute to the metaboreceptor component of the exercise pressor reflex. / McCord, Jennifer L.; Tsuchimochi, Hirotsugu; Kaufman, Marc.

In: Journal of Applied Physiology, Vol. 109, No. 5, 01.11.2010, p. 1416-1423.

Research output: Contribution to journalArticle

TY - JOUR

T1 - P2X2/3 and P2X3 receptors contribute to the metaboreceptor component of the exercise pressor reflex

AU - McCord, Jennifer L.

AU - Tsuchimochi, Hirotsugu

AU - Kaufman, Marc

PY - 2010/11/1

Y1 - 2010/11/1

N2 - The exercise pressor reflex is due to activation of thin fiber afferents within contracting muscle. These afferents are in part stimulated by ATP activation of purinergic 2X (P2X) receptors during contraction. Which of the P2X receptors contribute to the reflex is unknown; however, P2X2/3 and P2X3 receptor subtypes are good candidates because they are located on thin fiber afferents and are involved in sensory neurotransmission. To determine if P2X2/3 and P2X3 receptors evoke the metabolic component of the exercise pressor reflex, we examined the effect of two P2X2/3 and P2X3 antagonists, A-317491 (10 mg/kg) and RO-3 (10 mg/kg), on the pressor response to injections of α,β-methylene ATP (α,β-MeATP; 50 μg/kg), freely perfused static contraction, contraction of the triceps surae muscles while the circulation was occluded, and postcontraction circulatory occlusion in decerebrate cats. We found that the antagonists reduced the pressor response to α,β- MeATP injection (beforeΔ20 ± 3 mmHg; drugΔ11 ± 3 mmHg; P < 0.05), suggesting the antagonists were effective in blocking P2X2/3 and P2X3 receptors. P2X2/3 and P2X3 receptor blockade reduced the pressor response to freely perfused contraction (beforeΔ33 ± 5 mmHg; drugΔ15 ± 5 mmHg; P < 0.05), contraction with the circulation occluded (beforeΔ52 ± 7 mmHg; drugΔ20 ± 4 mmHg; P < 0.05), and during postcontraction circulatory occlusion (beforeΔ15 ± 1 mmHg; drug Δ 5 ± 1 mmHg; P < 0.05). Our findings suggest that P2X2/3 and P2X3 receptors contribute to the metabolic component of the exercise pressor reflex in decerebrate cats.

AB - The exercise pressor reflex is due to activation of thin fiber afferents within contracting muscle. These afferents are in part stimulated by ATP activation of purinergic 2X (P2X) receptors during contraction. Which of the P2X receptors contribute to the reflex is unknown; however, P2X2/3 and P2X3 receptor subtypes are good candidates because they are located on thin fiber afferents and are involved in sensory neurotransmission. To determine if P2X2/3 and P2X3 receptors evoke the metabolic component of the exercise pressor reflex, we examined the effect of two P2X2/3 and P2X3 antagonists, A-317491 (10 mg/kg) and RO-3 (10 mg/kg), on the pressor response to injections of α,β-methylene ATP (α,β-MeATP; 50 μg/kg), freely perfused static contraction, contraction of the triceps surae muscles while the circulation was occluded, and postcontraction circulatory occlusion in decerebrate cats. We found that the antagonists reduced the pressor response to α,β- MeATP injection (beforeΔ20 ± 3 mmHg; drugΔ11 ± 3 mmHg; P < 0.05), suggesting the antagonists were effective in blocking P2X2/3 and P2X3 receptors. P2X2/3 and P2X3 receptor blockade reduced the pressor response to freely perfused contraction (beforeΔ33 ± 5 mmHg; drugΔ15 ± 5 mmHg; P < 0.05), contraction with the circulation occluded (beforeΔ52 ± 7 mmHg; drugΔ20 ± 4 mmHg; P < 0.05), and during postcontraction circulatory occlusion (beforeΔ15 ± 1 mmHg; drug Δ 5 ± 1 mmHg; P < 0.05). Our findings suggest that P2X2/3 and P2X3 receptors contribute to the metabolic component of the exercise pressor reflex in decerebrate cats.

UR - http://www.scopus.com/inward/record.url?scp=78549234030&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78549234030&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.00774.2010

DO - 10.1152/japplphysiol.00774.2010

M3 - Article

C2 - 20798273

AN - SCOPUS:78549234030

VL - 109

SP - 1416

EP - 1423

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 5

ER -