Several studies have demonstrated that serotonergic and noradrenergic systems have
important roles in morphine analgesia and tolerance. However, the exact mechanism …

Abstract Background. Alpha 2 (α2)-adrenoceptor agonists may be useful for their potential to
increase or prolong opioid analgesia while attenuating the development of opioid tolerance …

This paper is the thirty-fourth consecutive installment of the annual review of research
concerning the endogenous opioid system. It summarizes papers published during 2011 …

Tolerance to the local antiallodynic effects of morphine, DPDPE ([d-Pen (2), d-Pen (5)]-
Enkephalin) or JWH-015 ((2-methyl-1-propyl-1H-indol-3-yl)-1-naphthalenylmethanone) after …

Cannabinoid CB1 and CB2 receptor antagonists may be useful for their potential to increase
or prolong opioid analgesia while attenuating the development of opioid tolerance. The aim …

Linalool, a terpene alcohol, has been shown to interact with the opioid system and N‐methyl‐
d‐aspartate (NMDA) receptor. Therefore, the effect of linalool on morphine dependence and …

Opioid receptor agonist drugs, such as morphine, are very effective for treating chronic and
severe pain; but, tolerance can develop with long-term use. Although there is a lot of …

Morphine is a drug of choice for the treatment of severe and chronic pain, but tolerance to
the antinociceptive effect limits its use. The development of tolerance to morphine has …

Ghrelin, a peptide hormone released from the gastric endocrine glands, shows analgesic
activity apart from its various physiological effects. Nevertheless, the effects of ghrelin …

Background Opioids are effective analgesics in the management of chronic pain. However,
their clinical use is hindered by adverse side effects such as addiction and analgesic …