Demonstration of antihistamine properties with AST-1: a bioactive extract from garden slugs (Diplosolenodes occidentalis).
Parched and ground whole garden slugs are claimed in rural Jamaican folklore practices to have useful effects in the treatment of bronchial asthma. Since this claim may be associated with respiratory dysfunction due to histamine from allergic sensitization, the authors investigated the effects of a semi-pure alcoholic extract (AST-1) on histamine-induced contraction of the guinea pig in vitro tracheal muscle preparation and cutaneous allergic responses in ovalbumin sensitized guinea pigs. Chemical analysis of AST-1 by column chromatography and thin layer chromatography indicated two compounds in the composition, but the molecular structures were not determined Pharmacological evaluation of AST-1 produced a concentration-dependent inhibition of histamine-induced contraction of the guinea pig tracheal muscle preparation. AST-1 also inhibited contraction of the tracheal muscle produced by selective H1 receptor stimulation with HTMT dimaleate. H2 receptors were not involved, as indicated by the absence of contraction with dimaprit hydrochloride, a selective H2 agonist. Also, in ovalbumin sensitized guinea pigs, AST-1 and diphenhydramine, a selective H1 antagonist, inhibited the cutaneous responses due to intradermal injection of histamine and ovalbumin. These results suggest that AST-1 has H1 anti-histamine properties which can inhibit histamine-induced tracheobronchial muscle contraction and cutaneous responses due to allergy.
Jacob
A
A
Department of Basic Medical Sciences, The University of the West Indies, Kingston 7, Jamaica.
Simon
O
O
Reese
P
P
Singh
P
P
D000818:Animals; D001685:Biological Factors / Q000494:pharmacology*; D002855:Chromatography, Thin Layer; D049851:Gastropoda; D006168:Guinea Pigs; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D007563:Jamaica; D008297:Male; D008519:Medicine, Traditional; D009119:Muscle Contraction / Q000187:drug effects*; D014132:Trachea / Q000187:drug effects / Q000502:physiology
D001685:Biological Factors; D006634:Histamine H1 Antagonists