Biomaterial Database

Histrionicotoxin and alkylguanidine interactions with the solubilized and membrane-bound muscarinic acetylcholine receptor from porcine atria. 1983

C Cremo, and M I Schimerlik

The interaction of alkylguanidines and decahydrohistrionicotoxin with the membrane-bound and solubilized muscarinic acetylcholine receptor (mAcChR) from porcine atria was described. Alkylguanidines with alkyl chain lengths from one to ten carbons displaced L-[3H]quinuclidinyl benzilate (L-[3H]QNB) competitively from a single class of sites for the membrane-bound mAcChR. From a plot of -1n Ki versus alkyl carbon chain number, a value of -(473 +/- 30) cal/mol was estimated as the energetic contribution per methylene group to the total binding energy. The binding of alkylguanidines to the digitonin/cholate solubilized mAcChR was complex in nature resulting in titration curves that did not obey the law of mass action for simple competitive inhibition at higher alkyl carbon numbers and a sigmoidal plot of -1n Ki versus carbon number. Decahydrohistrionicotoxin bound in a competitive manner versus L-[3H]QNB to both the membrane-bound (Ki = (6.9 +/- 1.4) X 10(-6) M) and the solubilized (Ki = (1.5 +/- 0.3) X 10(-5) M) preparations.

UI	MeSH Term	Description	Entries
D008566	Membranes	Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.	Membrane Tissue,Membrane,Membrane Tissues,Tissue, Membrane,Tissues, Membrane
D011950	Receptors, Cholinergic	Cell surface proteins that bind acetylcholine with high affinity and trigger intracellular changes influencing the behavior of cells. Cholinergic receptors are divided into two major classes, muscarinic and nicotinic, based originally on their affinity for nicotine and muscarine. Each group is further subdivided based on pharmacology, location, mode of action, and/or molecular biology.	ACh Receptor,Acetylcholine Receptor,Acetylcholine Receptors,Cholinergic Receptor,Cholinergic Receptors,Cholinoceptive Sites,Cholinoceptor,Cholinoceptors,Receptors, Acetylcholine,ACh Receptors,Receptors, ACh,Receptor, ACh,Receptor, Acetylcholine,Receptor, Cholinergic,Sites, Cholinoceptive
D006146	Guanidines	A family of iminourea derivatives. The parent compound has been isolated from mushrooms, corn germ, rice hulls, mussels, earthworms, and turnip juice. Derivatives may have antiviral and antifungal properties.
D006325	Heart Atria	The chambers of the heart, to which the BLOOD returns from the circulation.	Heart Atrium,Left Atrium,Right Atrium,Atria, Heart,Atrium, Heart,Atrium, Left,Atrium, Right
D000664	Amphibian Venoms	Venoms produced by frogs, toads, salamanders, etc. The venom glands are usually on the skin of the back and contain cardiotoxic glycosides, cholinolytics, and a number of other bioactive materials, many of which have been characterized. The venoms have been used as arrow poisons and include bufogenin, bufotoxin, bufagin, bufotalin, histrionicotoxins, and pumiliotoxin.	Frog Venoms,Toad Venoms,Amphibian Venom,Frog Venom,Toad Venom,Venom, Amphibian,Venom, Frog,Venom, Toad,Venoms, Amphibian,Venoms, Frog,Venoms, Toad
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
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog