Jd. Harkins et al., EFFECT OF FUROSEMIDE ON PHYSIOLOGICAL VARIABLES IN EXERCISING HORSES, American journal of veterinary research, 54(12), 1993, pp. 2104-2109
Twelve horses (6 Standardbreds and 6 Thoroughbreds) received IM inject
ions of furosemide (250 mg) or physiologic saline solution and perform
ed standard exercise tests, to assess the effects of furosemide and br
eed on blood gas values, PCV, plasma lactate concentration, and heart
rate during exercise. After furosemide administration, arterial and ve
nous blood pH values were significantly (P < 0.05) increased. Partial
pressures of O-2 and CO2 in arterial blood and of CO2 in venous blood
(Pa-O2, Pa-CO2, and PVCO2, respectively) were unaffected by furosemide
treatment, whereas venous partial pressures of O-2 (PVO2) were signif
icantly (P < 0.05) less during exercise after furosemide treatment, su
ggesting an increase in oxygen uptake by the exercising muscles or a c
hange in cardiac output. A significant (P < 0.05) difference was found
between Thoroughbred and Standardbred values for arterial and venous
pH, Pa-O2, Pa-CO2, plasma lactate concentration, and heart rate, sugge
sting that Standardbreds exercised at a relatively higher work rate th
an did Thoroughbreds.