Central hemodynamic effects of cocaine and ritodrine in the isolated, perfused rat heart.
OBJECTIVE
To explore the cardiac interactions of cocaine and ritodrine in pregnancy.


METHODS
Using the isolated, perfused rat-heart model, hearts from pregnant Sprague-Dawley rats were exposed to increasing concentrations of ritodrine: 25, 50, 100, and 250 ng/mL. Hearts of half of the animals, the experimental group, were exposed to cocaine (5 x 10(-6) mol/L). Left ventricular systolic pressure, heart rate, and contractility were measured.


RESULTS
Ritodrine had marked positive inotropic and chronotropic effects. Cocaine exposure resulted in smaller increases in all indices.


CONCLUSIONS
Cocaine blunted but did not obliterate the cardiac stimulatory effects of ritodrine in this model.
Kurtzman
J T
JT
Department of Obstetrics and Gynecology, University of North Carolina School of Medicine, Chapel Hill.
Thorp
J M
JM
Spielman
F J
FJ
Mueller
R A
RA
Cefalo
R C
RC
D000818:Animals; D003042:Cocaine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*; D010477:Perfusion; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D012312:Ritodrine / Q000494:pharmacology*; D013268:Stimulation, Chemical; D013599:Systole / Q000187:drug effects
D012312:Ritodrine; D003042:Cocaine