ISSN:
1432-1041
Keywords:
theophylline
;
beta-blocker
;
asthma
;
arterial blood pressure
;
inotropism
;
heart rate
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Medicine
Notes:
Summary The effects of theophylline upon cardiovascular function were studied in 8 male subjects, aged 22–33 years, before and during concomitant administration of metoprolol (50 mg every 6 h) and propranolol (40 mg every 6 h). Theophylline, as aminophylline (6.7–7.3 mg/kg) was given over 30 min. The theophylline level five minutes after completion of the aminophylline infusion was 15.9±1.8 µg/ml in the absence of beta blockade, 16.1±1.7 µg/ml during metoprolol, and 15.1±1.6 µg/ml during propranolol. Theophylline produced a 7% increase in mean arterial pressure which was not attenuated by either metoprolol or propranolol. Heart rate was not changed by theophylline. The QS2 Index (QS2I), a sensitive indicator of inotropism, was shortened from 488±16 to 476±16 msec (p〈0.01) by theophylline alone. After administration of metoprolol or propranolol, theophylline produced no shortening of the QS2I. Theophylline has a mild inotropic effect in healthy subjects. This effect is prevented by pretreatment with beta-adrenergic antagonists.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00637510
