Effects of serotonin re-uptake inhibition on ventilatory control in goats.
Fluoxetine (Prozac) inhibits serotonin (5-HT) re-uptake. thereby enhancing serotonergic effects. Since serotonin is known to affect ventilation in a variety of circumstances, we investigated the effects of chronic serotonin re-uptake inhibition with fluoxetine on selected ventilatory responses including: (1) eupnea; (2) the hypercapnic ventilatory response at rest; (3) the exercise ventilatory response and (4) repeated trials of hypercapnic exercise. Ventilatory and arterial blood gases were measured in goats (n = 5) at rest, during steady-state treadmill exercise, and during successive rest/exercise trials with increased respiratory dead space (0.4-0.6 L). Fluoxetine was administered (> or = 4 weeks, 1 mg/kg, SQ, SID) and protocols were repeated. Following fluoxetine, PaCO2 was increased in most conditions studied; however, no differences were seen in exercise PaCO2 regulation or ventilatory responses pre- versus post-fluoxetine. We conclude that chronic fluoxetine slightly depresses respiratory control at rest, but, has minimal effects during exercise or with mild hypercapnia during rest or exercise in goats.
Henderson
D R
DR
Department of Comparative Biosciences, University of Wisconsin, Madison 53706, USA. hendersd@svm.vetmed.wisc.edu
Konkle
D M
DM
Mitchell
G S
GS
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D005260:Female; D005473:Fluoxetine / Q000097:blood / Q000494:pharmacology*; D006041:Goats; D006935:Hypercapnia / Q000503:physiopathology; D009043:Motor Activity / Q000502:physiology; D012119:Respiration / Q000187:drug effects*; D017367:Selective Serotonin Reuptake Inhibitors / Q000097:blood / Q000494:pharmacology*
D005473:Fluoxetine; D017367:Selective Serotonin Reuptake Inhibitors