Mu receptors opioids

Mahajan SD, Schwartz SA, Shanahan TC, Chawda RP, Nair MP (2002) Morphine regulates gene expression of alpha- and beta-chemokines and their receptors on astroglial cells via the opioid mu receptor. J Immunol 169 3589-3599... 

Porreca, F., Tang, Q. B., Bian, D., Riedl, M., Elde, R., and Lai, J. (1998). Spinal opioid mu receptor expression in lumbar spinal cord of rats following nerve injury. Brain Res. 795, 197-203. 

Analgesia Opioid mu-receptor agonist Hydrated dextrates, citric acid, dibasic sodium phosphate, berry flavor, magnesium stearate, modified food starch, confectioner s sugar Cephalon... 

ADL-2-1294 (opioid mu receptor agonist) Adolor USA Conjunctivitis Phase II... 

Naloxone Opioid mu receptor antagonist used to reverse CNS depressant effects of... 

Tsai F-F, Fan S-Z, Yang Y-M, Chien K-L, Su Y-N, Chen L-K. Human opioid mu-receptor A118G polymorphism may protect against central pruritus by epidural morphine for post-cesarean analgesia. Acta Anaesthesiol Scand 2010 54 1265-9. 

Morphine acts on the mu receptor, and so do most of the clinically used opioid drugs. The detailed structure of these receptors has been described and we now have a reasonable understanding of their relative roles in physiological functions and in different pain states. 

There is little new with regard to the mu receptor, the main target for opioid drugs. The receptor is remarkably similar in structure and function in all species studied so animal studies will be good predictors for clinical applications. Although there have been suggestions of subtypes of the receptor, the cloned mu receptors have all been identical. 

These differences in the behavioural properties of the opioid receptor sub-types are of considerable interest because the clinical use of currently marketed opioid analgesic drugs is limited by their undesirable side-effects, which include respiratory depression, constipation and an abuse or dependence liability. These side-effects have been associated with mu receptor ac-... 

Both U-62066 (spiradoline) (10) and PD 117302 (12) are racemic mixtures of two enantiomers. The kappa opioid activity has been shown to reside in the (—) enantiomer, and in the case of U62066 the (-h) enantiomer is a weak mu receptor agonist [49, 50]. (See above for discussion on absolute stereochemistry.)... 

Opioid receptors are found in the dorsal horn as well as in other areas throughout the spinal cord and brain. Three major classes of opioid receptors exist mu receptors (/r), kappa receptors (k) and delta... 

It is a potent and long acting opioid with partial mu receptor agonist property. 25 times more potent than morphine. Effects are similar to morphine but constipation is less marked. It undergoes extensive presystemic elimination and therefore is... 

It is N-allyl analogue of oxymorphone, have a high affinity for mu receptor and lower affinity at delta and kappa sites. It selectively antagonizes the respiratory depression produced by opioids. After intravenous administration, it antagonizes all actions of morphine. It also blocks the actions of endogenous opioid peptides. 

Chen, Z.R., Irvine, R.J., Somogyi, A.A., Bochner, F. Mu receptor binding of some commonly used opioids and their metabolites. Life Sci. 1991, 48, 2165-2171. 

Hydrocodone is a semisynthetic opioid derived from codeine.18It is utilized as an analgesic and antitussive available for oral administration, often in combination with acetaminophen or ibuprofen. As a rule, potent analgesics containing a methoxyl group at position 3 (e.g., hydrocodone, K, = 19.8 nM) bind the mu receptor relatively weakly, but their O-demethylated metabolites (such as hydromorphone, Kt = 0.6 nM) bind more strangely. As with oxycodone, the possibility exists that some of their ability to relieve pain may actually derive from their active metabolites 48... 

Buprenorphine is derived from thebaine. It is a partial mu agonist with kappa antagonist activity. Buprenorphine has 25 to 50 times the potency of morphine. It is used to produce a longer-lasting analgesia than morphine. Effects of buprenorphine last longer because it is released more slowly from mu receptors than morphine. It is available as an injectable for intramuscular (IM) or intravenous administration in a 1-ml solution containing 0.3 mg buprenorphine (as buprenorphine HC1) for the relief of moderate to severe pain. It is also available to treat opioid dependence in the formulation of a tablet,51 alone or in combination with naloxone, in 2- or 8-mg... 

The existence of several classes of opioid receptors has therefore lead to the development of drugs that are somewhat more selective in the receptor class or subclass that they stimulate. In particular, drugs that selectively stimulate kappa or delta receptors may still provide sufficient analgesia, but will be less likely to provoke problems like respiratory depression and opioid abuse if they avoid or even block (antagonize) the mu receptors. Certain opioid drugs, for example, stimulate kappa receptors while avoiding or blocking... 

A new addition to this category is buprenorphine (Buprenex). This drug partially activates mu receptors but is an antagonist at kappa receptors. Because of these selective effects, buprenorphine has been advocated not only as an analgesic, but also as a treatment for opioid dependence and withdrawal.26 84 The use of this drug in treating opioid addiction is discussed in more detail later in this chapter. 

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