title: Pathogenic mechanisms of sand tampan toxicoses induced by the tick, Ornithodoros savignyi.
abstract: The tick, Ornithodoros savignyi has been implicated in inducing paralysis and tampan toxicosis. In this study, a basic toxin (TSGP4) was identified and the presence of an acidic toxin (TSGP2) was confirmed. Both basic and acidic toxins were more lethal than previously described, with TSGP4 (34microg) and TSGP2 (24microg) causing mortality of adult mice within 30min. Pathological effects on the cardiac system, notably of salivary gland extract on an isolated rat heart perfusion system and of purified toxins on mouse electrocardiogram patterns could be observed. TSGP4 caused Mobitz type ventricular block, while TSGP2 induced ventricular tachycardia. Conversely, fractions from reversed phase high performance liquid chromatography preparations caused paralysis-like symptoms of the limbs after only 48h. The toxins also differ from previously described tick paralysis toxins in terms of molecular behavior and properties. These results indicate that tampan toxicoses and tick paralysis are unrelated pathogenic phenomena.
authors.affiliation: Department of Biochemistry, University of Pretoria, South Africa.
authors.forename: Ben J
authors.initials: BJ
authors.lastname: Mans
authors.forename: Christiaan M L
authors.initials: CM
authors.lastname: Steinmann
authors.forename: Jacobus D
authors.initials: JD
authors.lastname: Venter
authors.forename: Abraham I
authors.initials: AI
authors.lastname: Louw
authors.forename: Albert W H
authors.initials: AW
authors.lastname: Neitz
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D066298:In Vitro Techniques; D019476:Insect Proteins / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D008297:Male; D051379:Mice; D009200:Myocardial Contraction / Q000187:drug effects; D026861:Ornithodoros / Q000472:pathogenicity / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012469:Salivary Glands / Q000378:metabolism; D013984:Tick Infestations; D013985:Tick Paralysis / Q000209:etiology* / Q000503:physiopathology; D014020:Tissue Extracts / Q000008:administration & dosage; D014118:Toxins, Biological / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D018754:Ventricular Dysfunction / Q000139:chemically induced / Q000503:physiopathology
chemical_list: D019476:Insect Proteins; D014020:Tissue Extracts; D014118:Toxins, Biological