Biomaterial Database

Colchicine competitively antagonizes glycine receptors expressed in Xenopus oocytes. 1998

T K Machu

Department of Pharmacology, Texas Tech University Health Sciences Center, Lubbock 79430, USA. phrtkm@ttushc.edu

Ligand-gated ion channel association with the cytoskeleton may play an important role in receptor distribution and function. However, the microtubule depolymerizing agent, colchicine, has inhibitory effects on glycine receptors that are independent of microtubule depolymerization. The actions of colchicine and other microtubule-modifying drugs were examined on glycine alpha1 and alpha2 receptors expressed in Xenopus oocytes. The potency of colchicine was much greater in alpha2 than alpha1 receptors, with IC50s of approximately 64 and 324 microM in alpha2 and alpha1 receptors, respectively. Colchicine inhibition of receptor function was instantaneous. Pre-incubation with colchicine failed to enhance its inhibition, and washout of colchicine's inhibition could be observed in 30 s. Incubation of oocytes on ice for 2 h to depolymerize microtubules failed to alter colchicine's antagonism of glycine receptors. Taxol, a microtubule polymerizing agent, and nocodazole, a depolymerizing drug, had no effect on receptor function when co-applied with glycine. The antagonism of glycine-mediated currents by colchicine (100-600 microM) was competitive. Thus, the action of colchicine at the agonist recognition site of the glycine receptor suggests that this drug should be used with care when studying microtubule-associated changes in ligand-gated ion channel function.

UI	MeSH Term	Description	Entries
D003078	Colchicine	A major alkaloid from Colchicum autumnale L. and found also in other Colchicum species. Its primary therapeutic use is in the treatment of gout, but it has been used also in the therapy of familial Mediterranean fever (PERIODIC DISEASE).	Colchicine, (+-)-Isomer,Colchicine, (R)-Isomer
D005998	Glycine	A non-essential amino acid. It is found primarily in gelatin and silk fibroin and used therapeutically as a nutrient. It is also a fast inhibitory neurotransmitter.	Aminoacetic Acid,Glycine, Monopotassium Salt,Glycine Carbonate (1:1), Monosodium Salt,Glycine Carbonate (2:1), Monolithium Salt,Glycine Carbonate (2:1), Monopotassium Salt,Glycine Carbonate (2:1), Monosodium Salt,Glycine Hydrochloride,Glycine Hydrochloride (2:1),Glycine Phosphate,Glycine Phosphate (1:1),Glycine Sulfate (3:1),Glycine, Calcium Salt,Glycine, Calcium Salt (2:1),Glycine, Cobalt Salt,Glycine, Copper Salt,Glycine, Monoammonium Salt,Glycine, Monosodium Salt,Glycine, Sodium Hydrogen Carbonate,Acid, Aminoacetic,Calcium Salt Glycine,Cobalt Salt Glycine,Copper Salt Glycine,Hydrochloride, Glycine,Monoammonium Salt Glycine,Monopotassium Salt Glycine,Monosodium Salt Glycine,Phosphate, Glycine,Salt Glycine, Monoammonium,Salt Glycine, Monopotassium,Salt Glycine, Monosodium
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014982	Xenopus laevis	The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.	Platanna,X. laevis,Platannas,X. laevi
D018009	Receptors, Glycine	Cell surface receptors that bind GLYCINE with high affinity and trigger intracellular changes which influence the behavior of cells. Glycine receptors in the CENTRAL NERVOUS SYSTEM have an intrinsic chloride channel. GlyA receptor is sensitive to STRYCHNINE and localized in the post-synaptic membrane of inhibitory glycinergic neurons. GlyB receptor is insensitive to strychnine and associated with the excitatory NMDA receptor.	Excitatory Glycine Receptors,GlyA Receptors,GlyB Receptors,Glycine A Receptors,Glycine B Receptors,Glycine Receptor alpha1,Glycine Receptors,Inhibitory Glycine Receptor,SIG Receptor,Strychnine-Insensitive Glycine Receptor,Strychnine-Sensitive Glycine Receptor,Glycine Receptor,Glycine Receptor, Inhibitory,Glycine Receptor, Strychnine-Insensitive,Glycine Receptor, Strychnine-Sensitive,Receptor, Glycine,Receptor, Inhibitory Glycine,Receptor, SIG,Receptor, Strychnine-Insensitive Glycine,Receptor, Strychnine-Sensitive Glycine,Receptors, GlyB,Strychnine Insensitive Glycine Receptor,Strychnine Sensitive Glycine Receptor
D018408	Patch-Clamp Techniques	An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.	Patch Clamp Technique,Patch-Clamp Technic,Patch-Clamp Technique,Voltage-Clamp Technic,Voltage-Clamp Technique,Voltage-Clamp Techniques,Whole-Cell Recording,Patch-Clamp Technics,Voltage-Clamp Technics,Clamp Technique, Patch,Clamp Techniques, Patch,Patch Clamp Technic,Patch Clamp Technics,Patch Clamp Techniques,Recording, Whole-Cell,Recordings, Whole-Cell,Technic, Patch-Clamp,Technic, Voltage-Clamp,Technics, Patch-Clamp,Technics, Voltage-Clamp,Technique, Patch Clamp,Technique, Patch-Clamp,Technique, Voltage-Clamp,Techniques, Patch Clamp,Techniques, Patch-Clamp,Techniques, Voltage-Clamp,Voltage Clamp Technic,Voltage Clamp Technics,Voltage Clamp Technique,Voltage Clamp Techniques,Whole Cell Recording,Whole-Cell Recordings