ADP is a vasodilator component from Lasiodora sp. mygalomorph spider venom

• Published in: Toxicon (Oxford) 2013-09, Vol.72, p.102-112
• Main Authors: Horta, C.C., Rezende, B.A., Oliveira-Mendes, B.B.R., Carmo, A.O., Capettini, L.S.A., Silva, J.F., Gomes, M.T., Chávez-Olórtegui, C., Bravo, C.E.S., Lemos, V.S., Kalapothakis, E.
• Format: Article
• Language: English
• Subjects: adenosine diphosphate; Adenosine Diphosphate - chemistry; Adenosine Diphosphate - pharmacology; Adenosine monophosphate; Adenosine Monophosphate - chemistry; ADP; Animals; antagonists; Araneae; Assaying; Blotting, Western; Brazil; Chemical Fractionation; edema; endothelial nitric oxide synthase; Endothelium; Endothelium - drug effects; erythema; fractionation; heart; humans; In Vitro Techniques; Inhibitors; Lasiodora; Mass Spectrometry; NG-Nitroarginine Methyl Ester - metabolism; Nitric oxide; Nitric Oxide Synthase - metabolism; Nuclear magnetic resonance; nuclear magnetic resonance spectroscopy; Nuclear Magnetic Resonance, Biomolecular; pain; Phosphorylation; Phosphorylation - drug effects; Rats; Spider; Spider Venoms - chemistry; Spiders; Spiders - chemistry; suramin; Suramin - chemistry; Vasodilation; Vasodilation - drug effects; Vasodilator Agents - chemistry; Vasodilator Agents - pharmacology; Venom; venoms; Western blotting
• ISSN: 0041-0101; 1879-3150
• DOI: 10.1016/j.toxicon.2013.06.006

Members of the spider genus Lasiodora are widely distributed in Brazil, where they are commonly known as caranguejeiras. Lasiodora spider venom is slightly harmful to humans. The bite of this spider causes local pain, edema and erythema. However, Lasiodora sp. spider venom may be a source of important pharmacological tools. Our research group has described previously that Lasiodora sp. venom produces bradycardia in the isolated rat heart. In the present work, we sought to evaluate the vascular effect of Lasiodora sp. venom and to isolate the vasoactive compounds from the venom. The results showed that Lasiodora spider venom induced a concentration-dependent vasodilation in rat aortic rings, which was dependent on the presence of a functional endothelium and abolished by the nitric oxide synthase (NOS) inhibitor L-NAME. Western blot experiments revealed that the venom also increased endothelial NOS function by increasing phosphorylation of the Ser1177 residue. Assay-directed fractionation isolated a vasoactive fraction from Lasiodora sp. venom. Mass spectrometry (MS) and nuclear magnetic resonance (NMR) assays identified a mixture of two compounds: adenosine diphosphate (ADP, approximately 90%) and adenosine monophosphate (AMP, approximately 10%). The vasodilator effects of Lasiodora sp. whole venom, as well as ADP, were significantly inhibited by suramin, which is a purinergic P2-receptor antagonist. Therefore, the results of the present work indicate that ADP is a main vasodilator component of Lasiodora sp. spider venom. •Lasiodora mygalomorph spider venom caused a pronounced concentration-dependent vasodilator response in isolated rat aorta.•The vasodilator effects of Lasiodora sp. venom on the rat aorta were endothelium and nitric oxide-dependent.•ADP is a main vasodilator component from Lasiodora sp. venom.