%0 Journal Article
%T Neuromuscular activity of Bothrops neuwiedi pauloensis snake venom in mouse nerve-muscle preparations
%A Durigon
%A A. M.
%A Borja-Oliveira
%A C. R.
%A Dal Belo
%A C. A.
%A Oshima-Franco
%A Y.
%A Cogo
%A J. C.
%A Lapa
%A A. J.
%A Souccar
%A C.
%A Rodrigues-Simioni
%A L.
%J Journal of Venomous Animals and Toxins including Tropical Diseases
%D 2005
%I Centro de Estudos de Venenos e Animais Pe?onhentos - CEVAP, Universidade Estadual Paulista - UNESP
%R 10.1590/S1678-91992005000100004
%X the pharmacological effects of bothrops neuwiedi pauloensis venom on mouse phrenic nerve-diaphragm (pnd) preparations were studied. venom (20 mg/ml) irreversibly inhibited indirectly evoked twitches in pnd preparations (60 ¡À 10% inhibition, mean ¡À sem; p<0.05; n=6). at 50 mg/ml, the venom blocked indirectly and directly (curarized preparations) evoked twitches in mouse hemidiaphragms. in the absence of ca2+, venom (50 mg/ml), produced partial blockade only after an 80 min incubation, which reached 40.3 ¡À 7.8% (p<0.05; n=3) after 120 min. venom (20 mg/ml) increased (25 ¡À 2%, p< 0.05) the frequency of giant miniature end-plate potentials in 9 of 10 end-plates after 30 min and the number of miniature end-plate potentials which was maximum (562 ¡À 3%, p<0.05) after 120 min. during the same period, the resting membrane potential decreased from - 81 ¡À 1.4 mv to - 41.3 ¡À 3.6 mv 24 fibers; p<0.01; n=4) in the end-plate region and from - 77.4 ¡À 1.4 to -44.6 ¡À 3.9 mv (24 fibers; p<0.01; n=4) in regions distant from the end-plate. these results indicate that b. n. pauloensis venom acts primarily at presynaptic sites. they also suggest that enzymatic activity may be involved in this pharmacological action.
%K giant mepps
%K myotoxicity
%K neurotoxicity
%K presynaptic action.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S1678-91992005000100004&lng=en&nrm=iso&tlng=en