Antinociception and Hypertension.A review of available data indicates that acute and chronic increases in arterial blood pressure (ABP) are associated with antinociception in animals and hypoalgesia in humans. The primary issues of concern are whether increases in ABP are directly responsible for altered nociceptive function, and the extent to which carotid sinus, aortic depressor, and/or vagal afferents contribute to the changes in nociceptive function.