Comparative study between peripherally and centrally acting sublethal and lethal doses of Leiurus quinquestriatus scorpion venom in rabbits: The usefulness of the sodium channel blocker lidocaine

Abstract Background: Scorpion envenomation is common among desert dwellers, affecting several systems and resulting in multiple organ dysfunction (MOD) or failure (MOF), mainly due to their action on Na+ channels. Although scorpion venoms toxins do not pass the blood brain barrier, their CNS effects are prominent, occurring in conjunction with, or as an aftermath of peripheral actions of the venom. Objective: To determine the ability of venom of the common scorpion Leiurus quinquestriatus (LQQ) to induce MOD or MOF when injected into rabbits in micro quantities centrally (intracere- broventricularly, i.c.v.) or macro amounts peripherally (s.c. or i.v.). Also, to assess if the Na+ channel blocker lidocaine can protect rabbits from the resultant manifestations. Methods: Rabbits were injected with LQQ venom centrally or peripherally, in either sublethal or lethal doses, and MOD or MOF determined by assessing: cardiac output (CO), estimated hepatic blood flow (EHBF), biochemical parameters indicative of cardiac/hepatic/renal and pancreatic functions, blood pressure (BP), survival, lung/body index (LBI, indicative of pulmonary edema), and/or histological changes in hearts, lungs, livers plus kidneys. In pre-treatment experiments, lidocaine was injected 40 min before venom and protective ability examined.