Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0344307 (analgesia)
 28,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes in the content of angiotensin II (A II) immunoreactivity (ir) in rat spinal perfusate induced by electroacupuncture (EA) stimulation of different frequencies were measured by radioimmunoassay (RIA). The results were analyzed in relation to the role of opioid receptor. (1) 2 Hz EA produced a 20% (P > 0.05) decrease in A II -ir content in the spinal perfusate. 15 Hz EA produced an even more decrease (62%, P < 0.01), whereas 100 Hz produced a significant increase (65%, P < 0.05). (2) The release in spinal A II -ir produced by 15 Hz EA was reversed by the opioid antagonist naloxone to a of 125% highter than that of the control (P < 0.05), suggesting that 15 Hz EA may accelerate the release of endogenous opioids to suppress the release of A II. (3) This was substantiated by the finding that intrathecal (i.t.) injection of the selective mu agonist ohmefentanyl produced a dramatic suppression (20%, P < 0.05) of A II release, but not by delta and kappa agonist. (4) Intrathecal injection of salarasin, the angiotensin receptor antagonist, produced a significant potentiation of the analgesia produced by 100 Hz EA, but not that produced by 2 or 15 Hz EA. It is concluded that 15 Hz EA may induce the release of endogenous opioids acting on mu opioid receptor so as to suppress A II release, and that 100 Hz EA may accelerate the release of A II serving as a brake for 100 Hz EA-induced analgensia. Removal of the brake by angiotensin antagonist may be advised as an adjunct for the potentiation of 100 Hz EA-induced analgesia.
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PMID:[Angiotensin II release and anti-electroacupuncture analgesia in spinal cord]. 938 52

The angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are a well known entity and have been used in therapeutics for various indications like hypertension, myocardial infarction and CHF. However, there is a renewed interest in these compounds in terms of their effects on pain perception in animals as well as in human beings. They have yielded contradictory results, showing hyperalgesia in some studies but analgesia in others. Hence this study was undertaken to evaluate the effect of Ramipril (an ACE-I) and Losartan (an ARB) on pain perception in human volunteers using cola caps and handcuff of sphygmomanometer. A total of 30 healthy, normotensive individuals with no previous history of intake of analgesics during or 4 weeks prior to the study were selected after an informed consent. The first group received a single dose of placebo, the second group received Ramipril (2.5 mg) & the third group received Losartan (50 mg). Pain perception threshold (the point at which an individual first experiences pain) and the maximum tolerated pain were assessed using the above method. The control group showed no significant changes in pain threshold, but the group receiving either Ramipril or Losartan showed a decline in threshold for maximum tolerated pain. Only Ramipril and not Losartan decreased the pain perception threshold. Our study revealed that single dose treatment of healthy volunteers with Ramipril and Losartan may cause algesia as early as after ingestion of the first dose and further studies are needed to study their long term effects on pain perception.
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PMID:Modulation of pain perception by ramipril and losartan in human volunteers. 1883 57