title: Isolation, purification and partial chemical characterization of a lethal factor from common indian toad (Bufo melanostictus, Schneider) skin extract.
abstract: Indian toad (Bufo melanostictus, Schneider) skin extract (TSE) is pharmacologically potent and probably contains several bioactive compounds [Das et. al., Indian J Pharmacol, 28 (1996) 72]. A lethal factor was isolated and purified by neutral alumina column chromatography followed by HPLC. Spectroscopic (UV, IR, FAB-MASS) study indicated that the lethal factor (TSE-LF) was a 254 Da long chain compound with carbonyl, hydroxyl and ester as functional groups. LD50 of TSE-LF was found to be 3.5 mg/kg (iv). Biological study showed that TSE-LF possesses hypotensive, cardiotoxic, neurotoxic activity and produced death by apnoea in experimental animal. Cyproheptadine antagonised TSE-LF induced contraction of isolated smooth muscle indicating involvement of histamine/serotonin receptors. TSE-LF induced neurotoxic action on chick biventer cervices was mediated through Ca2+ ion.
authors.affiliation: Department of Physiology, University of Calcutta, India.
authors.forename: M
authors.initials: M
authors.lastname: Das
authors.forename: S C
authors.initials: SC
authors.lastname: Dasgupta
authors.forename: A
authors.initials: A
authors.lastname: Gomes
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D002025:Bufonidae; D002319:Cardiovascular System / Q000187:drug effects; D002352:Carrier Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity; D002851:Chromatography, High Pressure Liquid; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007928:Lethal Dose 50; D051381:Rats; D012867:Skin / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D002352:Carrier Proteins; C030325:anthrax toxin