THE TERM INTRINSIC SENSITIVITY AND ITS APPLICATION TO THE VASOPRESSOR ACTION OF NORADRENALINE AND VASOPRESSIN IN ARTERIOSCLEROTIC RATS

  • 1 January 1980
    • journal article
    • research article
    • Vol. 247  (1) , 31-38
Abstract
The intrinsic sensitivity [i.s.], as the quotient of the maximum of the cumulative dose-response curve of an agonist in a pathologically or otherwise changed target object to the maximum of the cumulative dose-response curve of the agonist in the normal target object, was used to characterize the reaction ability for vasocontriction of the blood vessel system of the isolated perfused hind legs of arterioslcerotic rats (pretreatment with vitamin D2) on the injection of noradrenaline [norepinephrine] (NA), 8-lysine-vasopressin (LVP) and a vasopressin preparation with an admixture of oxytocin (VA), respectively. I.s. was 0.80 to NA, 0.32 to LVP but 1.27 to VA. The reaction ability for vasoconstriction of the blood vessel system of vitamin D2-pretreated arteriosclerotic rats is decreased for certain agonists, but is increased for others. The pD2 value of NA was 4.69 in normal rats and 4.85 in vitamin D2-pretreated rats; the respective data were 5.80 and 6.32 for LVP and 3.58 and 3.88 for VA. Dose response curves of NA, LVP, VA, prostaglandin F2.alpha. and angiotensin II were compared.