Assessing supraspinal modulation of pain perception in individuals at riskfor hypertension

In this study we tested the hypothesis that hypoalgesia in individuals at r isk for hypertension is related to enhanced activation of supraspinal pain modulation systems. Supraspinal inhibition of pain signals was assessed usi ng a diffuse noxious inhibitory control paradigm, in which a noxious condit ioning stimulus was used to suppress pain in response to a noxious test sti mulus applied to a remote area of the body. Specifically, the nociceptive f lexion reflex (NFR) was assessed in 113 healthy young adults before, during , and after exposure to forearm tourniquet ischemia. Consistent with previo us evidence of hypoalgesia in individuals at risk for hypertension, offspri ng of hypertensive individuals exhibited significantly higher NFR threshold s than offspring of normotensive persons. Although NFR activity was signifi cantly decreased in all participants during concomitant application of fore arm ischemia, the degree of attenuation of NFR activity was not significant ly different as a function of risk for hypertension.