Biomaterial Database

Effects of topical anesthetics on tympanic membrane structure. 1988

J Strutz, and R Blessing, and C Zöllner

Department of Oto-Rhino-Laryngology, University of Freiburg, Federal Republic of Germany.

Topical application of a local anesthetic agent can induce adequate insensibility to pain, and therefore can avoid the use of general anesthesia or invasive infiltration techniques for myringotomy or the insertion of a tympanostomy tube. A comparative study was conducted on a guinea pig animal model to determine the effects of three agents on the structure of the tympanic membrane: 5% tetracaine base dissolved in dimethylsulfoxide (DMSO), pure DMSO, and Bonain's solution. Survival times ranged from 1 day to 3 months. Following removal from the animals, membranes were embedded in Spurr and cut in semithin sections. Signs of mild or severe external otitis were frequent; to avoid non-specific results, infected specimens were not evaluated. Bonain's solution caused loss of the epidermis and mucosal epithelium within 1 day of treatment. The connective tissue layers of the drum were severely hyperplastic after a survival time of 1 month. Tetracaine base in DMSO caused a loss of epithelium and mucosal cells in 3 days. Regeneration started within 7 days and a restitution to integrity was seen after 3 months in drums treated with tetracaine base or DMSO alone.

UI	MeSH Term	Description	Entries
D008610	Menthol	A monoterpene cyclohexanol produced from mint oils.	Cyclohexanol, 5-methyl-2-(1-methylethyl)-,Menthol, (1alpha,2beta,5alpha)-Isomer
D010636	Phenols	Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
D003042	Cocaine	An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake.	Cocaine HCl,Cocaine Hydrochloride,HCl, Cocaine,Hydrochloride, Cocaine
D004121	Dimethyl Sulfoxide	A highly polar organic liquid, that is used widely as a chemical solvent. Because of its ability to penetrate biological membranes, it is used as a vehicle for topical application of pharmaceuticals. It is also used to protect tissue during CRYOPRESERVATION. Dimethyl sulfoxide shows a range of pharmacological activity including analgesia and anti-inflammation.	DMSO,Dimethyl Sulphoxide,Dimethylsulfoxide,Dimethylsulphinyl,Dimethylsulphoxide,Dimexide,Rheumabene,Rimso,Rimso 100,Rimso-50,Sclerosol,Sulfinylbis(methane),Rimso 50,Rimso50,Sulfoxide, Dimethyl,Sulphoxide, Dimethyl
D004338	Drug Combinations	Single preparations containing two or more active agents, for the purpose of their concurrent administration as a fixed dose mixture.	Drug Combination,Combination, Drug,Combinations, Drug
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
D000287	Administration, Topical	The application of drug preparations to the surfaces of the body, especially the skin (ADMINISTRATION, CUTANEOUS) or mucous membranes. This method of treatment is used to avoid systemic side effects when high doses are required at a localized area or as an alternative systemic administration route, to avoid hepatic processing for example.	Drug Administration, Topical,Administration, Topical Drug,Topical Administration,Topical Drug Administration,Administrations, Topical,Administrations, Topical Drug,Drug Administrations, Topical,Topical Administrations,Topical Drug Administrations
D000779	Anesthetics, Local	Drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. They act on any part of the nervous system and on every type of nerve fiber. In contact with a nerve trunk, these anesthetics can cause both sensory and motor paralysis in the innervated area. Their action is completely reversible. (From Gilman AG, et. al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed) Nearly all local anesthetics act by reducing the tendency of voltage-dependent sodium channels to activate.	Anesthetics, Conduction-Blocking,Conduction-Blocking Anesthetics,Local Anesthetic,Anesthetics, Topical,Anesthetic, Local,Anesthetics, Conduction Blocking,Conduction Blocking Anesthetics,Local Anesthetics,Topical Anesthetics
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
D012996	Solutions	The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Solution