Ultra-low doses (ULD) of the opioid receptor antagonists, naloxone and naltrexone,
augment the analgesic actions of morphine, block the induction of tolerance, and reverse …

Background: The development of analgesic tolerance following chronic morphine
administration can be a significant clinical problem. Preclinical studies demonstrate that …

Intraperitoneal (ip) injection of toxins, such as the bacterial endotoxin lipopolysaccharide
(LPS), is associated with a well-characterized increase in sensitivity to painful stimuli …

Development of analgesic tolerance and withdrawal-induced pain enhancement present
serious difficulties for the use of opioids for pain control. Although neuronal mechanisms to …

Long-term use of opioid analgesics is limited by tolerance development and undesirable
adverse effects. Paradoxically, spinal administration of ultra-low-dose (ULD) G-protein …

Recent preclinical and clinical studies have demonstrated that cotreatments with extremely
low doses of opioid receptor antagonists can markedly enhance the efficacy and specificity …

Degree: M. Sc. DegreeYear: 2002 Institute: Queen''s University at Kingston (Canada)
Adviser: Khem Jhamandas. Opioids traditionally produce an inhibitory effect on neuronal …

Introduction: Opioid use to treat chronic pain is limited by the development of tolerance and
increased risk of side effects as dosages are increased to compensate for loss of analgesia …

The magnitude of tolerance and dependence is defined in part by agonist concentration and
duration of receptor exposure. Therefore, in the face of continued exposure to an opioid …

Low-dose naloxone-precipitated withdrawal hyperalgesia is a reliable indicator of physical
dependence after chronic morphine treatment. A remarkably similar long-lasting (> 3–4 h) …