For comparable blood pressures, plasma noradrenaline is disproportionately higher in patients with phaechromocytoma than in those with essential hypertension. The 'pressor-dose' of noradrenaline or its reciprocal, the reactivity index, were abnormal in patients with phaechromocytoma before surgery and were normalized by surgical removal of the phaechromocytoma. There was a significant correlation between blood pressures and the logarithm of plasma noradrenaline concentrations. The higher dose of exogenous noradrenaline required in patients with phaechromocytoma for a given rise in blood pressure seems to be the expression of the higher levels of endogenous noradrenaline rather than true decreased reactivity.
|Publication status||Published - 1981|
ASJC Scopus subject areas