Receptor ligands endogenous

Of the several classes of receptors for endogenous chemical signals [3], two are used as postsynaptic receptors in synaptic transmission ligand-gated ion channels (LGICs) and G protein-coupled receptors (GPCRs Fig. 1). Due to the large number of transmitters and the existence of several receptor types for almost all, postsynaptic receptor activation is the most diversified step of synaptic transmission. Table 1 shows selected neurotransmitter receptors. 

THE QUEST FOR THE ENDOGENOUS BENZODIAZEPINE RECEPTOR LIGAND ( ENDOZEPINES )... 

Since the cloning of the cannabinoid receptors, their endogenous ligands, the endocannabinoids, have received a great deal of research interest. A number of recent review articles have extensively covered the end-ocannabinoid system [10-12], so the coverage in this article will be brief. 

INTERACTION OF OPIOID RECEPTORS WITH ENDOGENOUS PEPTIDE LIGANDS... 

Protein receptors for endogenous ligands (e.g., hormones, neurotransmitters) share some common properties. They contain a ligand-binding domain, where the hormone or neurotransmitter attaches, and an effector domain, which translates the binding into some from of action. 

Romero J, de Miguel R, Garcia-Palomero E, Fernandez-Ruiz JJ, Ramos JA. (1995). Time-course of the effects of anandamide, the putative endogenous cannabinoid receptor ligand, on extrapyramidal function. Brain Res. 694(1-2) 223-32. 

Substances with a neuromodulatory effect on brain neurotransmitters by direct actions of specific receptors that modify the actions of the transmitters listed include prostaglandins, adenosine, enkephalins, substance P, cholecystokinin, endorphins, endogenous benzodiazepine receptor ligands, and possibly histamine. CNS, central nervous system. NMDA, N-methyl-D-aspartate. Strych, strychnine. 

Later, we described the isolation of a second type of cannabinoid receptor ligand, 2-arachidonoyl glycerol (2-AG) (K = 5-85 0.12 xM), an ester isolated from canine gut. " This was the first putative endogenous cannabinoid receptor ligand isolated from a peripheral tissue. Later, Sugiura et al isolated independently this compound from brain. 

SugiuraT, Kondo S, Sukagawa A, Nakane S, Shinoda A, Itoh K, Yamashita A, Waku K, 2-Arachidonoylglycerol A possible endogenous cannabinoid receptor ligand in brain, Biochem Biophys Res Commun 215 89—97, 1995. 

Although prostanoids can activate peroxisome proliferator-activated receptors (PPARs) if added in sufficient concentration in vitro, it remains questionable whether these compounds attain concentrations sufficient to function as endogenous nuclear-receptor ligands in vivo. 

Receptor subtypes Endogenous ligands Selective antagonists ... 

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