Assessment of opiate modulation of pain and nociceptive responding in young adults with a parental history of hypertension

Effects of opioid blockade on nociceptive flexion reflex thresholds and nociceptive responding in hypertensive and normotensive individuals

“…The current findings are congruent with recent pharmacological blockade studies which failed to find opioid mediation of cold, ischemic or electrocutaneous pain in patients with essential hypertension Ring et al, 2008). In addition, these results concur with previous blockade studies examining the effects of opioid antagonists on pain in individuals with normal or highnormal blood pressure that have also yielded little (McCubbin and Bruehl, 1994;McCubbin et al, 2006) or no (Bruehl et al, 2002;France et al, 2005;Schobel et al, 1998) support for an opioid hypothesis for hypertensive hypoalgesia. The absence of opioid antagonist effects on the nociception flexion reflex has also been noted in previous research examining the effects of opioid blockade in young, presumably normotensive, healthy adults.…”

“…Although sex differences in pain ratings have been reported in the literature, we believe the lack of sex differences for the nociceptive flexion reflex is not particularly curious. Indeed, none of our previous studies found sex differences in the nociceptive flexion reflex (e.g., al 'Absi et al, 2005;Edwards et al, 2001;France et al, 2005). However, it must be conceded that some other studies have found a sex effect for the nociceptive flexion reflex (e.g., France & Suchowiecki, 2001;Page & France, 1997).…”

“…Further, recent blockade studies have also failed to find opioid mediation of cold, ischemic or electrocutaneous pain in patients with essential hypertension Ring et al, 2008). In addition, France et al (2005) have observed that nociceptive flexion reflex thresholds were not affected by naltrexone in young normotensive adults at varying risk for hypertension. However, to date, no studies have investigated the role of opioids on nociception flexion reflex activity in patients with essential hypertension.…”

Nociceptive flexion reflex thresholds and pain during rest and computer game play in patients with hypertension and individuals at risk for hypertension

“…In humans, the evidence in favour of opioid dysfunction is mostly negative (e.g., Bruehl et al, 2002;France et al, 2005;Ring et al, 2007;Schobel et al, 1998;cf. McCubbin and Bruehl, 1994;McCubbin et al, 2006) whereas the evidence for baroreceptor activation is more mixed (e.g., al 'Absi et al, 2005;Edwards et al, 2001Edwards et al, ,2003aGuasti, Zanotta, Mainardi, et al, 2002;McIntyre et al, 2006;Rau et al, 1995).…”

Effects of naltrexone on electrocutaneous pain in patients with hypertension compared to normotensive individuals

“…Several pain experiments have investigated the effects of opioid antagonists on pain in individuals with normal or high-normal blood pressure. However, their results have yielded either little (McCubbin & Bruehl, 1994;McCubbin et al, 2006) or no (Bruehl, Chung, Ward, Johnson & McCubbin, 2002;Schobel, Hanwerker, Schmieder, Heusser, Dominiak, & Luft, 1998;France et al, 2005) support for an opioid mechanism underlying variations in sensitivity to pain with blood pressure status. It is possible that these studies failed to find support for an opioid mechanism because they tested young adults with blood pressures in the normal range, and therefore, research on patients with confirmed essential hypertension offers a more definitive test.…”