Dobutamine stress echocardiography in healthy adult male rats.
BACKGROUND
Dobutamine stress echocardiography is used to investigate a wide variety of heart diseases in humans. Dobutamine stress echocardiography has also been used in animal models of heart disease despite the facts that the normal response of healthy rat hearts to this type of pharmacological stress testing is unknown. This study was performed to assess this normal response.


METHODS
15 normal adult male Wistar rats were evaluated. Increasing doses of dobutamine were infused intravenously under continuous imaging of the heart by a 12 MHz ultrasound probe.


RESULTS
Dobutamine stress echocardiography reduced gradually LV diastolic and systolic dimensions. Ejection fraction increased by a mean of +24% vs. baseline. Heart rate increased progressively without reaching a plateau. Changes in LV dimensions and ejection fraction reached a plateau after a mean of 4 minutes at a constant infusion rate.


CONCLUSIONS
DSE can be easily performed in rats. The normal response is an increase in heart rate and ejection fraction and a decrease in LV dimensions. A plateau in echocardiographic measurements is obtained after 4 minutes of a constant infusion rate in most animals.
Plante
Eric
E
Groupe de Recherche sur les Valvulopathies, Centre de Recherche Hôpital Laval, Institut de Cardiologie de Québec, Université Laval, Québec, Canada. eric.plante@crhl.ulaval.ca
Lachance
Dominic
D
Drolet
Marie-Claude
MC
Roussel
Elise
E
Couet
Jacques
J
Arsenault
Marie
M
D000818:Animals; D004280:Dobutamine / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004452:Echocardiography / Q000379:methods*; D005080:Exercise Test; D006339:Heart Rate / Q000187:drug effects; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000187:drug effects*; D007262:Infusions, Intravenous; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013318:Stroke Volume / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects*
D004280:Dobutamine