Opioids naturally occurring

ENDOGENOUS OPIOIDS Naturally occurring opioids in the body includes three classes of neurotransmitters—the endorphins, enkephalins, and dynorphins. 

Opioids. Morphine [57-27-2] C yH NO, (8) the most prevalent and analgesicaHy potent of the naturally occurring opium alkaloids (qv), has been used as an anesthetic premedication for over one hundred years (93). It has also been used as an iv analgesic for the last four decades, and, since 1969, in high doses as an anesthetic agent (117). 

The word opioid is used to refer to the overall class including the semi- and fully-synthetic agents, but the word opiate only refers to the naturally occurring opioids such as heroin, opium, and morphine. 

Erspamer Y, Melchiorri P, Falconieri-Erspamer G, et al. Deltorphins a family of naturally occurring peptides with high affinity and selectivity for opioid binding sites. Proc Natl Acad Sci USA 1989 86 5188-5192. 

Roth, B.L., Baner, K., Westkaemper, R., Siebert, D., Rice, K.C., Steinberg, S., Ernsberger, P. and Rothman, R.B. (2002) Salvinorin A a potent naturally occurring nonnitrogenous kappa opioid selective... 

Roth BL, Baner K, Westkaemper R, et al., Salvinorin A A potent naturally occurring nonnitrogenous K opioid selective agonist, Proc Natl Acad Sci USA 99 11934-11939,2002. 

Like morphine, codeine is a naturally occurring opioid found in the poppy plant. Codeine is indicated for the treatment of mild to moderate pain and for its antitussive effects. It is widely used as an opioid antitussive because at antitussive doses it has few side effects and has excellent oral bioavailability. Codeine is metabolized in part to morphine, which is believed to account for its analgesic effect It is one of the most commonly used opioids in combination with nonopioids for the relief of pain. The administration of 30 mg of codeine in combination with aspirin is equivalent in analgesic effect to the administration of 65 mg of codeine. The combination of the drugs has the advantage of reducing the... 

The third group consists of naturally occurring and synthetic peptides with opioid-like properties. The opioid peptides were discovered during the search for endogenous ligands of the opioid receptors and share the same action and side-effect profile as the non-peptidic compounds... 

Opioid derivatives used to treat diarrhea are listed in Table 27-3. Opium tincture (laudanum) and camphorated opium tincture (paregoric) are naturally occurring opiates that are very potent inhibitors of peristalsis. These natural agents are still available for treating diarrhea, but they have essentially been replaced by newer opioids such as diphenoxylate and loperamide. These newer opioids are somewhat less potent but may produce fewer side effects. 

A unique characteristic of amphibian opioid peptides is the presence in the second N-terminal position of a D-amino acid residue that confers to these compounds high resistance against enzyme degradation. Hence amphibian opioids, unique among naturally occurring opioid peptides, can act centrally after peripheral administration. 

Bals-KubikR, Herz A, Shippenberg TS (1988) fi-endorphin-(l-27) is a naturally occurring antagonist of the reinforcing effects of opioids. Naunyn-Schmiedeberg s Arch Pharmacol 338 392-396... 

There are naturally-occurring opioid agonists from plants, such as morphine, which owes its dramatic psychopharmacological effects in mammals to an interaction with receptors for enkephalins and endorphins. As evidence increases that insects and other arthropods utilize neuroactive peptides as neuromessengers (16), it becomes more likely that some of the plant opiates are defensive chemicals having a "psychomanipulant" type of mechanism. 

Like Rohypnol, GHB is a central nervous system (CNS) depressant, which, when tested on animals, induces a sleep-like state in doses ranging from 0.1 to 1.5 milligrams per kilogram.33 Although many neurotransmitter systems are affected by treatment with GHB, evidence supports the hypothesis that GHB itself acts as a neurotransmitter. This implies that GHB is a naturally occurring chemical in the body that is necessary for normal nervous system functions. Administered as a drug, GHB has been shown to temporarily inhibit the release of dopamine in the brain.34 This inhibition is followed by a marked increase in the release of both dopamine and naturally occurring opioids, such as endorphins.35... 

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