Opioid receptors endogenous ligands

The identification of the opioid peptides in the mid-1970s opened up a whole new area for the development of opioid receptor ligands. The endogenous opioid peptides, both mammalian and amphibian (see below), have served as lead compounds that have been extensively modified to enhance potency, receptor type selectivity, stability, and/or decrease conformational flexibility. Peptide ligands selective for both fx and d opioid receptors are found in more than one type of peptide sequence. Thus some enkephalin analogs, as well as the recently discovered endomorphins, analogs of... 

Endogenous opioid peptides are the wide variety of endogenous peptides isolated since 1975 which are the natural ligands for the opioid receptors. The peptides... 

Nociceptin is an opioid peptide, which is the endogenous ligand for the opioid receptor-like protein (ORL). 

INTERACTION OF OPIOID RECEPTORS WITH ENDOGENOUS PEPTIDE LIGANDS... 

The mu, kappa, and delta opioid receptors have been found to interact with endogenous peptide ligands that share certain pharmacologic properties with opioid drugs. These peptide ligands are derived from at least three different prohormones located in both... 

Marijuana and hashish are derivatives of the cannabis sativa plant 919 Cannabinoid effects in the CNS are mediated by the CB1 receptor 919 Endocannabinoids are endogenous ligands for the CB1 receptor 919 Endocannabinoids serve as retrograde messengers 920 There are many similarities between endogenous opioid and cannabinoid systems 921... 

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... 

Okuda-Ashitaka, E., Tachibana, S., Houtani, T Minami, T Masu, Y., Nishi, M., Takeshima, H., Sugimoto, T., Ito, S. Identification and characterization of an endogenous ligand for opioid receptor homologue ROR-C its involvement in allodynic response to innocuous stimulus, Brain Res. Mol. Brain Res. 1996, 43, 96-104. 

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