Autoregulatory index, adrenergic responses, and interaction between adrenoreceptors and prostacyclin in the coronary system of rainbow trout
✍ Scribed by Agnisola, C.; Mustafa, T.; Hansen, J.K.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 962 KB
- Volume
- 275
- Category
- Article
- ISSN
- 0022-104X
No coin nor oath required. For personal study only.
✦ Synopsis
Some salient regulatory properties of the coronary system in nonworking heart preparation of trout are studied, in particular: (1) the pressure dependence of coronary resistance;
(2) the reactivity to adrenergic compounds; and (3) the interaction between prostacyclin and specific adrenergic agonists. Coronary resistance was not influenced by variation in ventricle weight or heart rate among various preparations used throughout this study. A positive autoregulatory index (ArI) was determined in the pressure range of 2.5-3.5 kPa, suggesting the existence of an active vasoconstrictive response probably involving local regulatory mechanisms. Noradrenaline was a powerful vasoconstrictor and prostacyclin (PG12) was a vasodilator when perfused separately. Both the ul-agonist phenylephrine and the u2-agonist clonidine induced dose-dependent