Emerging clinical and preclinical evidence suggests that a compound displaying high affinity for μ, κ, and δ opioid (MOP, KOP, and DOP) receptors and antagonist activity at each, coupled with moderate affinity and efficacy at nociceptin opioid peptide (NOP) receptors will have utility as a relapse prevention agent for multiple types of drug abuse. Members of the orvinol family of opioid ligands...

Various studies have investigated the role of central opioid peptides in feeding behavior; however, only a few have addressed the participation of opioids in the control of salt appetite. The present study investigated the effect of intracerebroventricular injections of the δ-opioid antagonist, naltrindole (5, 10 and 20 nmol/rat) and the agonist, deltorphin II (2.5, 5, 10 and 20 nmol/rat) on sa...

Opioid receptors of the mu-, delta- and kappa-subtypes mediate the potent analgesic and addictive actions of opioid drugs. They also regulate responses to pain, stress and emotions when activated by endogenous opioid peptides. Recently, mice lacking opioid receptors or opioid peptides have been produced by gene targeting, providing molecular tools to study opioid function in vivo. Observations ...

This presentation will review basic and clinical concepts on pain mechanisms underlying opioid analgesia. It describe the structure, function, cellular signaling of receptors; endogenous exogenous receptor ligands; as well central peripheral sites actions. The also discuss novel opioid-based therapeutic strategies, developed from recently gained knowledge structures signaling, patholo...

Opioid receptors, MORP, DORP and KORP, belong to the family A of G protein coupled receptors (GPCR), and have been found to modulate a large number of physiological functions, including mood, stress, appetite, nociception and immune responses. Exogenously applied opioid alkaloids produce analgesia, hedonia and addiction. Addiction is linked to alterations in function and responsiveness of all t...

Opioids are widely prescribed pain relievers with multiple side effects and potential complications. They produce analgesia via G-protein-protein coupled receptors: μ-, δ-, κ-opioid and opioid receptor-like 1 receptors. Bivalent ligands targeted to the oligomerized opioid receptors might be the key to developing analgesics without undesired side effects and obtaining effective treatment for opi...

one of the main components of the stress system is hypothalamus- pituitary-adrenal (hpa) axis. acute activation of µ-opioid receptors increases the activity of the hpa axis, leading to release of acth and corticosterone. glucocorticoids can change behaviors, depend on age but there were no evidences about the interaction between age, opioid system and glucocorticoids. in this experiment, effect...

To fi nd appropriate and effective treatment options for chronic pain syndromes is a challenging task. Multimodal treatment approach has been gaining acceptance for chronic pain. However, combining treatments, such as acupuncture, with rational pharmacology is still in its infancy. Acupuncture infl uences the opioid and cannabinoid system through releasing endogenous receptor ligands. Low dose ...

Background: S. alopecuroides, Z. officinale and M. officinalis are used traditionally in the treatment of pain. Objective: To evaluate the plants effects in the rat formalin test and their activity on the opioid receptors. Methods: Each rat was placed individually in a cage for 30 min to get acclimated. Then 0.05 mL of 10% formalin was injected subcutaneously into the dorsal surface of the r...

The presence of endogenous opioid peptides in different testicular cell types has been extensively characterized and provides evidence for the participation of the opioid system in the regulation of testicular function. However, the exact role of the opioid system during the spermatogenesis has remained controversial since the presence of the mu-, delta- and kappa-opioid receptors in spermatoge...