Biomaterial Database

Desensitization of the isolated guinea pig ileum to antihistaminic agents. 1983

I Onnen, and G Olive

Guinea pig ileum developed in vitro a progressive desensitization to the antihistaminic agents mepyramine and benadryl. This desensitization had uncommon characteristics: (1) at the 6.5-9 h period of the experiments, it consisted only of a decreased rate of action of the drugs (1.66 fold and 2 fold increases in the 2 min Kb value of mepyramine and benadryl respectively), without variation in the equilibrium Kb values; (2) it was not a drug effect since control strips (strips exposed to the first dose of antihistaminic agent after 5.5 h in vitro) also showed a decreased rate of action of the drugs (1.58 fold and 1.6 fold increases in the 2 min Kb value of mepyramine and benadryl respectively), without variation in the Kbe values. The desensitization also did not depend on the bathing medium or on the amount of available histamine receptors. The only explanation of the desensitization is a slowing in the antihistaminic agent-receptor reaction either in its access stage or less probably in its interaction stage.

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
D009130	Muscle, Smooth	Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)	Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
D011738	Pyrilamine	A histamine H1 antagonist. It has mild hypnotic properties and some local anesthetic action and is used for allergies (including skin eruptions) both parenterally and locally. It is a common ingredient of cold remedies.	Mepyramine,Pyranisamine,Anthisan,Boots Bite & Sting Relief,Kriptin,Mepyramine Maleate,Pyrilamine Maleate,Maleate, Mepyramine,Maleate, Pyrilamine
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
D004155	Diphenhydramine	A histamine H1 antagonist used as an antiemetic, antitussive, for dermatoses and pruritus, for hypersensitivity reactions, as a hypnotic, an antiparkinson, and as an ingredient in common cold preparations. It has some undesired antimuscarinic and sedative effects.	Benhydramin,Diphenylhydramin,2-Diphenylmethoxy-N,N-dimethylethylamine,Allerdryl,Benadryl,Benylin,Benzhydramine,Dimedrol,Diphenhydramine Citrate,Diphenhydramine Citrate (1:1),Diphenhydramine Hydrochloride,Diphenylhydramine,Dormin,Citrate, Diphenhydramine,Hydrochloride, Diphenhydramine
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
D006634	Histamine H1 Antagonists	Drugs that selectively bind to but do not activate histamine H1 receptors, thereby blocking the actions of endogenous histamine. Included here are the classical antihistaminics that antagonize or prevent the action of histamine mainly in immediate hypersensitivity. They act in the bronchi, capillaries, and some other smooth muscles, and are used to prevent or allay motion sickness, seasonal rhinitis, and allergic dermatitis and to induce somnolence. The effects of blocking central nervous system H1 receptors are not as well understood.	Antihistamines, Classical,Antihistaminics, Classical,Antihistaminics, H1,Histamine H1 Antagonist,Histamine H1 Receptor Antagonist,Histamine H1 Receptor Antagonists,Histamine H1 Receptor Blockaders,Antagonists, Histamine H1,Antagonists, Histamine H1 Receptor,Antihistamines, Sedating,Blockaders, Histamine H1 Receptor,First Generation H1 Antagonists,H1 Receptor Blockaders,Histamine H1 Blockers,Receptor Blockaders, H1,Antagonist, Histamine H1,Classical Antihistamines,Classical Antihistaminics,H1 Antagonist, Histamine,H1 Antagonists, Histamine,H1 Antihistaminics,Sedating Antihistamines
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