Effect of acute alpha adrenergic stimulation on cardiac function.
BACKGROUND
Phenylephrine (PE) is a alpha-adrenergic agent commonly administered by perfusion and anesthesia. It is important to identify the effect of PE, especially on cardiac function. This study was intended to show the effects of PE on cardiac function in the murine model via pressure-volume loops.


METHODS
Six C57BL/6J twelve-week-old female mice were studied prior to and following PE administration at 50 microg/kg IV. In vivo pressure-volume loops were recorded at both time points.


RESULTS
There was an expected increase in maximum arterial pressure by 30% (p < 0.001) and end-systolic pressure by 34% (p < 0.001). However, there was a decrease in cardiac output by 30% (p = 0.0006), ejection fraction by 36% (p = 0.0003) and stroke volume by 25% (p < 0.004).


CONCLUSIONS
This study demonstrates that PE has an effect on cardiac function beyond increasing vascular resistance. The data suggest the negative effects of PE on cardiac function may be related to stimulation of cardiac alpha-adrenergic receptors.
Dunaway
Stacy
S
Sarver Heart Center, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA.
Yu
Qianli
Q
Larson
Douglas F
DF
D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D002302:Cardiac Output / Q000187:drug effects*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D010656:Phenylephrine / Q000008:administration & dosage / Q000494:pharmacology*; D011941:Receptors, Adrenergic / Q000378:metabolism; D013318:Stroke Volume / Q000187:drug effects
D000316:Adrenergic alpha-Agonists; D011941:Receptors, Adrenergic; D010656:Phenylephrine