Biomaterial Database

Guanidines as analogs of histamine and antihistamines on the isolated guinea-pig ileum. 1976

L Rezende, and C R Diniz, and M Mares-Guia

The present work describes the interaction of phenylguanidine and cyclohexylguanidine with receptor structures of the isolated guinea-pig ileum. It is suggested that phenylguanidine in the range of 0.2-2 mM, acts in a way similar to histamine. At lower concentrations in the bath, phenylguanidine and cyclohexylguanidine, behave as competitive antagonists of histamine, with Ki values close to 0.1 mM and 0.4 mM, respectively. At higher concentrations phenylguanidine acts as agonist with a Kn near 0.3 mM; the Kn for histamine was found to be 0.127 muM, in agreement with previous data from the literature. The agonistic action of phenylguanidine is inhibited by promethazine and atropine, which have Ki values of 0.342 muM and 0.575 muM, respectively. Cyclohexylguanidine is devoid of spasmogenic activity, and this was attributed to the lack of aromatic character and to the bulkiness of the cyclohexyl side chain.

UI	MeSH Term	Description	Entries
D007082	Ileum	The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D011968	Receptors, Histamine	Cell-surface proteins that bind histamine and trigger intracellular changes influencing the behavior of cells. Histamine receptors are widespread in the central nervous system and in peripheral tissues. Three types have been recognized and designated H1, H2, and H3. They differ in pharmacology, distribution, and mode of action.	Histamine Binding Sites,Histamine Receptors,Histamine Receptor,Binding Sites, Histamine,Receptor, Histamine,Sites, Histamine Binding
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.
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D006632	Histamine	An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.	Ceplene,Histamine Dihydrochloride,Histamine Hydrochloride,Peremin
D006633	Histamine Antagonists	Drugs that bind to but do not activate histamine receptors, thereby blocking the actions of histamine or histamine agonists. Classical antihistaminics block the histamine H1 receptors only.	Antihistamine,Antihistamines,Histamine Antagonist,Antagonist, Histamine,Antagonists, Histamine
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
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In