Pathogenic mechanisms of sand tampan toxicoses induced by the tick, Ornithodoros savignyi

• Published in: Toxicon (Oxford) Vol. 40; no. 7; pp. 1007 - 1016
• Main Authors: MANS, Ben J, STEINMANN, Christiaan M. L, VENTER, Jacobus D, LOUW, Abraham I, NEITZ, Albert W. H
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Science 01.07.2002
• Subjects: Animal poisons toxicology. Antivenoms; Animals; Biological and medical sciences; Chromatography, High Pressure Liquid; In Vitro Techniques; Insect Proteins - chemistry; Insect Proteins - metabolism; Insect Proteins - toxicity; Male; Medical sciences; Mice; Myocardial Contraction - drug effects; Ornithodoros - pathogenicity; Ornithodoros - physiology; Rats; Rats, Sprague-Dawley; Salivary Glands - metabolism; Tick Infestations; Tick Paralysis - etiology; Tick Paralysis - physiopathology; Tissue Extracts - administration & dosage; Toxicology; Toxins, Biological - chemistry; Toxins, Biological - metabolism; Toxins, Biological - toxicity; Ventricular Dysfunction - chemically induced; Ventricular Dysfunction - physiopathology; Heart; Rat; Arrhythmia; Motor system disorder; Pathogenesis; Toxicity; Extract; Acari; Paralysis; Neurological disorder; Parasitiformes; Nervous system diseases; Rodentia; Animal origin; Salivary gland; Toxin; Arachnida; Vertebrata; Mammalia; Argasidae; Mouse; Ixodida; Arthropoda; Animal; Ornithodoros; Isolation; Circulatory system; Invertebrata
• ISSN: 0041-0101; 1879-3150
• DOI: 10.1016/s0041-0101(02)00098-3

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.