title: Histamine H2 receptor blockade augments blood pressure responses to acute submaximal exercise in males.
abstract: Histamine is a potent vasodilator that has been found to increase during exercise. We tested the hypothesis that histamine would attenuate blood pressure (BP), cardiac output (CO), and vascular resistance responses to short-term, submaximal dynamic exercise during H2 receptor blockade. Fourteen healthy men (20-29 years of age) were studied. Systolic (SBP), diastolic (DBP), and mean arterial (MAP) BP and heart rate (HR) were assessed at rest and during the last minute of 10 min of submaximal cycling exercise (60% of peak oxygen consumption) in the absence and presence of histamine H2 receptor blockade (ranitidine, 300 mg). Stroke volume (SV) (impedance cardiography) and plasma norepinephrine (NE) were measured, and CO, rate × pressure product (RPP), and total peripheral resistance (TPR) were calculated. Plasma levels of histamine were also measured. H2 blockade had no effects on any variables at rest. During exercise, SBP (184 ± 3 mm Hg vs. 166 ± 2 mm Hg), MAP (121 ± 2 mm Hg vs. 112 ± 5 mm Hg), and RPP (25.9 ± 0.8 × 10(3) mm Hg·beats/min vs. 23.5 ± 0.8 × 10(3) mm Hg/beats·min) were greater during blocked conditions (P < 0.05), and an interaction was observed for TPR. SV, DBP, HR, and NE levels were unaffected by blockade. Plasma histamine increased from 1.83 ± 0.14 ng/mL at rest to 2.33 ± 0.23 ng/mL during exercise (P < 0.05) and was not affected by H2 blockade (1.56 ± 0.23 ng/mL vs. 1.70 ± 0.24 ng/mL). These findings suggest that, during submaximal exercise, histamine attenuates BP, vascular resistance, and the work of the heart via activation of H2 receptors and that these effects occurred primarily in the vasculature and not in the myocardium.
authors.affiliation: a Graduate School of Physical Education, Kyung Hee University, Yongin, Korea.
authors.forename: Hyung-Woo
authors.initials: HW
authors.lastname: Doh
authors.affiliation: b Department of Internal Medicine, Division of Cardiovascular Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Charles L
authors.initials: CL
authors.lastname: Stebbins
authors.affiliation: a Graduate School of Physical Education, Kyung Hee University, Yongin, Korea.
authors.forename: Hyun-Min
authors.initials: HM
authors.lastname: Choi
authors.affiliation: a Graduate School of Physical Education, Kyung Hee University, Yongin, Korea.
authors.forename: Joonsung
authors.initials: J
authors.lastname: Park
authors.affiliation: a Graduate School of Physical Education, Kyung Hee University, Yongin, Korea.
authors.forename: Hosung
authors.initials: H
authors.lastname: Nho
authors.affiliation: a Graduate School of Physical Education, Kyung Hee University, Yongin, Korea.
authors.forename: Jong-Kyung
authors.initials: JK
authors.lastname: Kim
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination; D002302:Cardiac Output / Q000502:physiology; D015444:Exercise; D006339:Heart Rate; D006632:Histamine / Q000097:blood; D006635:Histamine H2 Antagonists / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D009638:Norepinephrine / Q000097:blood; D010101:Oxygen Consumption; D010807:Physical Endurance; D011899:Ranitidine / Q000008:administration & dosage; D011970:Receptors, Histamine H2 / Q000378:metabolism; D013318:Stroke Volume / Q000502:physiology; D014655:Vascular Resistance / Q000502:physiology; D055815:Young Adult
chemical_list: D006635:Histamine H2 Antagonists; D011970:Receptors, Histamine H2; D006632:Histamine; D011899:Ranitidine; D009638:Norepinephrine
keywords: cycling; cyclisme; norepinephrine; norépinéphrine; produit tension-fréquence; ranitidine; rate × pressure product; stroke volume; volume d’éjection systolique