A growing literature has reported a significant reduction in pain sensitivity among hypertensioe animals and humans. One of the key questions about this finding is whether a reduced sensitivity to pain can be observed in normotensive individuals who go on to develop high blood pressure. Blood pressure was re-assessed in one hundred and fifteen 19 year-old boys initially tested at age 14, when they were also presented with a pain stimulus (mechanical finger pressure). Analyses indicated that information regarding pain sensitivity improved prediction of changes in blood pressure beyond that afforded by differences in blood pressure at age 14, parental history of hypertension, and body mass index. Similar results were found in comparable analyses predicting 24-hour blood pressure recorded in one hundred and seventeen of the young men at age 22. Significant associations were also observed between pain sensitivity in 14 year-olds and 24-hour heart rate variability in various frequency bands at age 22, suggesting increased sympathetic and reduced parasympathetic tone among individuals less sensitive to pain. In order to further assess the relationship between autonomic function and pain sensitivity, one hundred and sixteen adolescent boys were assessed for pain sensitivity and autonomic responses to orthostatic challenge. Analyses indicated that exaggerated autonomic responses to postural change were associated with reduced pain sensitivity. Finally, to examine the potential role of endogenous opioids in blood pressure-related hypoalgesia, a group of young normotensive men were administered low-frequency transcutaneous electrical nerve 5 stimulation (TENS), which has been demonstrated to elicit endogenous opioid release, prior to being presented with two painful stimuli (electric shock and arm ischemia). A negative association between pain and resting blood pressure was significantly strengthened by administration of low-frequency TENS. The resu
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.82837 |
| Date | January 2002 |
| Creators | Campbell, Tavis S. |
| Contributors | Ditto, Blaine (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Psychology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001984266, proquestno: AAINQ88431, Theses scanned by UMI/ProQuest. |
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