title: Inhibition of cyclooxygenase attenuates the blood pressure response to plantar flexion exercise in peripheral arterial disease.
abstract: Prostanoids are produced during skeletal muscle contraction and subsequently stimulate muscle afferent nerves, thereby contributing to the exercise pressor reflex. Humans with peripheral arterial disease (PAD) have an augmented exercise pressor reflex, but the metabolite(s) responsible for this augmented response is not known. We tested the hypothesis that intravenous injection of ketorolac, which blocks the activity of cyclooxygenase, would attenuate the rise in mean arterial blood pressure (MAP) and heart rate (HR) evoked by plantar flexion exercise. Seven PAD patients underwent 4 min of single-leg dynamic plantar flexion (30 contractions/min) in the supine posture (workload: 0.5-2.0 kg). MAP and HR were measured on a beat-by-beat basis; changes from baseline in response to exercise were determined. Ketorolac did not affect MAP or HR at rest. During the first 20 s of exercise with the most symptomatic leg, ΔMAP was significantly attenuated by ketorolac (2 ± 2 mmHg) compared with control (8 ± 2 mmHg, P = 0.005), but ΔHR was similar (6 ± 2 vs. 5 ± 1 beats/min). Importantly, patients rated the exercise bout as "very light" to "fairly light," and average pain ratings were 1 of 10. Ketorolac had no effect on perceived exertion or pain ratings. Ketorolac also had no effect on MAP or HR in seven age- and sex-matched healthy subjects who performed a similar but longer plantar flexion protocol (workload: 0.5-7.0 kg). These data suggest that prostanoids contribute to the augmented exercise pressor reflex in patients with PAD.
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania mmuller1@hmc.psu.edu.
authors.forename: Matthew D
authors.identifier: http://orcid.org/0000-0002-7411-8816
authors.initials: MD
authors.lastname: Muller
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.
authors.forename: Rachel C
authors.identifier: http://orcid.org/0000-0001-8001-1946
authors.initials: RC
authors.lastname: Drew
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Ross
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Blaha
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.
authors.forename: Aimee E
authors.initials: AE
authors.lastname: Cauffman
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.
authors.forename: Marc P
authors.initials: MP
authors.lastname: Kaufman
authors.affiliation: Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.
authors.forename: Lawrence I
authors.initials: LI
authors.lastname: Sinoway
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D016022:Case-Control Studies; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D015444:Exercise; D005260:Female; D005528:Foot / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D020910:Ketorolac / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D058729:Peripheral Arterial Disease / Q000378:metabolism / Q000503:physiopathology*
chemical_list: D016861:Cyclooxygenase Inhibitors; D020910:Ketorolac
keywords: cyclooxygenase; exercise physiology; intermittent claudication