Does plasma from essential hypertensive subjects increase mean arterial pressure in a rat model compared to plasma from normotensive subjects?
Plasma from essential hypertensive subjects contains a novel circulating factor that increases mean arterial pressure and stimulates calcium uptake in vascular smooth muscle.
The pressor responses to dialyzed plasma extracts from normotensive (n = 15) and essential hypertensive (n = 14) human subjects were evaluated in anesthetized Sprague-Dawley rats. Hypertensive but not normotensive plasma raised mean arterial pressure (23.6 +/- 3.6 versus -0.5 +/- 2.5 mmHg, P less than 0.0001), and this effect was correlated significantly with its ability to stimulate 45Ca uptake in rat tail artery vascular smooth muscle (r = 0.883, P less than 0.002). These data suggest a humoral contribution to the pathophysiology of essential hypertension in at least some individuals. The time-course and molecular weight distribution of the dialyzed plasma suggest that this effect is not due to known vasopressor substances, but to a factor we tentatively term plasma hypertensive factor.
LEWANCZUK et al. (1990) studied this question.