Paper Information

Title: 

INTRATHECAL ADMINISTRATION OF EPINEPHRINE INHIBITS AND REVERSES ANALGESIC TOLERANCE TO MORPHINE IN RATS

Type: POSTER
Author(s): SATARIAN L.,JAVAN M.,FATH ELAHI Y.
 
 
 
Name of Seminar: IRANIAN CONGRESS OF PHYSIOLOGY AND PHARMACOLOGY
Type of Seminar:  CONGRESS
Sponsor:  PHYSIOLOGY AND PHARMACOLOGY SOCIETY, MASHHAD UNIVERSITY OF MEDICAL SCIENCE
Date:  2007Volume 18
 
 
Abstract: 

Introduction: Several researches have reported that stress is able to inhibit the development of morphine tolerance via activating of Hypothalamic-Pituitary-Adrenal (HPA) axis. In the current study we tried to examine the effect of epinephrine, the product of adrenal medulla, on the development of morphine tolerance.
Methods: Analgesic tolerance was induced by intrathecal (i.t.) injection of morphine 15
mg/kg, twice a day for 5 days. To study the effect of epinephrine on morphine tolerance, epinephrine (2, 5, 10 or 20 g/kg, i.t.) was administrated 15 minutes before morphine injection. Analgesia was assessed using tail flick test.
Results: In animals which received combined treatments of morphine and epinephrine in doses 2, 5, 10 or 20 mg/kg for 5 days, at 6th day, morphine produced a more potent analgesia comparing with animals received saline and morphine during days 1-5. When tolerance was induced during first 5 days, co-administration of epinephrine and morphine during second 5 days reduced the initial tolerance as it as mentioned by potent analgesia at day 11th.
Conclusion: Our results showed that i.t. administration of epinephrine is able to inhibit and reverse the analgesic tolerance to morphine. It also suggests the possible role of adrenal medulla and epinephrine in mediating the inhibitory effect of stress and HPA activation of the development of analgesic tolerance to morphine.

 
Keyword(s): 
 
Yearly Visit 10   tarjomyar
 
Latest on Blog
Enter SID Blog