The evolutionary origin and diversification of the reptilian venom system is described. The resolution of higher-order molecular phylogenetics has clearly established that a venom system is ancestral to snakes. The diversification of the venom system within lizards is discussed, as is the role of venom delivery in the behavioural ecology of these taxa (particularly Varanus komodoensis). The mor...

most specialized feeding mechanisms among vertebrates. The biomechanics and kinematics of prey ingestion have been documented from several snake taxa, although the full diversity of ingestive mechanics has only recently been appreciated (Cundall and Greene, 2000). Less attention has been paid to prey capture and, in particular, the mechanics of venom injection (Savitzky, 1980; Kochva, 1987). Ve...

UNLABELLED The scorpion Mesobuthus martensii is the most populous species in eastern Asian countries, and several toxic components have been identified from their venoms. Nevertheless, a complete proteomic profile of the venom of M. martensii is still not available. In this study, the venom of M. martensii was analyzed by comprehensive proteomic approaches. 153 fractions were isolated from the ...

In the life of the fire ant, Solenopsis invicta, venom plays several important roles, including prey capture, defense, and anti-microbial action. Although this venom's chemistry, pharmacology, and effects on humans have been extensively studied, its patterns of synthesis and use have not. We determined the ability of different-aged workers to synthesize venom, and measured the amount of venom w...

The effect of Indian red scorpion (Mesobuthus tamulus concanesis, Pocock; MBT) venom was investigated on isolated rat right atrial preparations. MBT venom (0.001-3.0 micrograms/ml) exhibited a peculiar concentration-response pattern with respect to rate. The venom concentrations between 0.001-0.01 microgram/ml increased the atrial rate (phase I), followed by a relative decrease with 0.03-0.3 mi...

Temporary paralysis is a rare manifestation of envenoming following the yellow Iranian scorpion, Odontobuthus doriae (O. doriae). Thus, to elucidate the underlying mechanism, we investigated the neurotoxic effect of venom in the sciatic nerve, the possible mechanism in a mice model. The neurotoxicity and temperature effects in the venom-induced neurotoxicity were examined using the mouse sciati...

Temporary paralysis is a rare manifestation of envenoming following the yellow Iranian scorpion, Odontobuthus doriae (O. doriae). Thus, to elucidate the underlying mechanism, we investigated the neurotoxic effect of venom in the sciatic nerve, the possible mechanism in a mice model. The neurotoxicity and temperature effects in the venom-induced neurotoxicity were examined using the mouse sciati...

Background: Immunotherapy is the only specific treatment for scorpion envenomation. In the present study, the protective effects of polyvalent antivenom against histopathological complications in kidneys and marker changes (BUN and creatinine) induced by Mesobuthus eupeus (Me) scorpion venom was investigated in anesthetized rabbits. Methods: Twenty four rabbits were randomized into four gro...

A new procedure for determining the amount of venom ejected by a bite of a poisonous snake was established. The procedure consists of exposing a fresh piece of rabbit muscle to an attack by a poisonous nake, extracting the injected venom from the piece, determining the toxic activity of the extract and calculating the amount of venom ejected. We confirmed that about 90 % of the injected venom w...

The noradrenergic innervation of Bothrops jararaca venom gland is thought to be important in the production and secretion of venom. We investigated the characteristics of the alpha-adrenoceptor in the venom gland and its role in venom production. This receptor had relatively low sensitivity to noradrenaline (pD(2)=4.77+/-0.09, N=7) and to phenylephrine (pD(2)=3.77+/-0.06, N=11). The receptor be...