Differential venous effects of isoprenaline in conscious rats

Aly Abdelrahman, Catherine C.Y. Pang*

*المؤلف المقابل لهذا العمل

نتاج البحث: المساهمة في مجلةمقالمراجعة النظراء

17 اقتباسات (Scopus)

ملخص

The role β-adrenoceptors in the control of venous tone is not clear. This study examines the dose-response effects of isoprenaline, a non-selective β-adrenoceptor agonist, on mean circulatory filling pressure (MCFP), an index of body venous tone, in conscious and unrestrained rats. Dose-response curves of isoprenaline were constructed in three groups of rats, namely, I, intact; III, pretreated with the ganglionic blocker hexamethonium; and V, pretreated with noradrenaline. Three additional groups, Groups II, IV and VI, served as time controls and were treated similar to I, III and V, respectively, except that they were given normal saline in place of isoprenaline. The infusion of isoprenaline in intact rats dose dependently decreased mean arterial pressure (MAP) and increased heart rate (HR) and MCFP while in the ganglionic-blocked rat, it caused similar effects on MAP and HR but had no significant effects on MCFP. In rats given noradrenaline, isoprenaline again decreased MAP and increased HR and, in contrast to the other two groups, it decreased MCFP. The results show that isoprenaline has variable venous effects depending on existing venous tone. It causes reflex-mediated venoconstriction under normal conditions due to its hypotensive effects and direct venodilatation when venous tone is elevated by the infusion of noradrenaline.

اللغة الأصليةEnglish
الصفحات (من إلى)321-327
عدد الصفحات7
دوريةEuropean Journal of Pharmacology
مستوى الصوت190
رقم الإصدار3
المعرِّفات الرقمية للأشياء
حالة النشرPublished - نوفمبر 13 1990
منشور خارجيًانعم

ASJC Scopus subject areas

  • ???subjectarea.asjc.3000.3004???

بصمة

أدرس بدقة موضوعات البحث “Differential venous effects of isoprenaline in conscious rats'. فهما يشكلان معًا بصمة فريدة.

قم بذكر هذا