Decreased ventilatory response to exercise by dopamine-induced inhibition of peripheral chemosensitivity.
The contribution of the peripheral chemoreflex to the ventilatory response to exercise and aerobic exercise capacity remains incompletely understood. Low-dose dopamine has been reported to specifically inhibit the peripheral chemoreceptors. We therefore investigated the effects of intravenous dopamine (3 microg kg(-1)min(-1)) on cardiopulmonary exercise test (CPET) variables in 13 healthy young male subjects. The study was prospective, placebo-controlled, and randomized with more than 24h between placebo and dopamine administrations. During the CPET, dopamine decreased the .V(E)/.V(CO2) output slope (24.61+/-1.84 vs. 23.09+/-1.81, placebo vs. Dopamine respectively, p=0.025), without affecting maximum workload, .V(E) and O(2) uptake. In conclusion, our study reveals that inhibition of peripheral chemoreflex function with dopamine decreases the .V(E)/.V(CO2) slope during dynamic exercise, with no change in aerobic exercise capacity.
Janssen
C
C
Department of Cardiology, Erasme University Hospital, 808 Lennik Road, Brussels, Belgium. chrisrv.janssen@gmail.com
Beloka
S
S
Kayembe
P
P
Deboeck
G
G
Adamopoulos
D
D
Naeije
R
R
van de Borne
P
P
D000328:Adult; D002316:Cardiotonic Agents / Q000494:pharmacology*; D002628:Chemoreceptor Cells / Q000187:drug effects* / Q000502:physiology; D004298:Dopamine / Q000494:pharmacology*; D004311:Double-Blind Method; D017079:Exercise Tolerance / Q000187:drug effects; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects*; D011446:Prospective Studies; D012123:Pulmonary Ventilation / Q000187:drug effects*; D055815:Young Adult
D002316:Cardiotonic Agents; D004298:Dopamine