Naloxone pro-drug rescues morphine induced respiratory depression in Sprague-Dawley rats.
Respiratory depression is the main obstacle for the safe administration of morphine for acute pain after injury. Due to this complication, new delivery methods are needed to insure that safe and effective doses of opioid analgesics are administered during emergencies. A depot formulation containing a naloxone pro-drug was designed to release the antidote when morphine causes dangerous hypoxic conditions in the blood. The aim of this work was to test the naloxone release in vivo in response to a severe overdose of morphine in the Sprague-Dawley rat model. Non-invasive two-chamber plethysmography was used to monitor and record respiration and to test the capability of the naloxone pro-drug to respond to and rescue morphine-induced respiratory depression in the animal. We show that the pro-drug formulation can both prevent and reverse severe morphine induced respiratory depression. The animal model demonstrates that co-administration of the naloxone pro-drug reliably antagonizes profound respiratory depressive effects of morphine.
Department of Physiology & Pharmacology, School of Medicine, Oregon Health & Science University, Portland, OR 97239-3098, USA.
Michael
M
Wallisch
Nehad M
NM
El Rody
Baohua
B
Huang
Dennis R
DR
Koop
James R
JR
Baker
George D
GD
Olsen
D000701:Analgesics, Opioid / Q000633:toxicity*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D008297:Male; D009020:Morphine / Q000633:toxicity*; D009270:Naloxone / Q000008:administration & dosage / Q000493:pharmacokinetics*; D009292:Narcotic Antagonists / Q000008:administration & dosage / Q000493:pharmacokinetics*; D010991:Plethysmography; D011355:Prodrugs / Q000008:administration & dosage / Q000493:pharmacokinetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012131:Respiratory Insufficiency / Q000139:chemically induced / Q000188:drug therapy*
D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D011355:Prodrugs; D009270:Naloxone; D009020:Morphine