The neuromuscular and skeletal muscle actions of @entity32766 kaouthia snake venom were studied in @entity1 ( @entity35 left hemidiaphragm) and avian ( @entity1573 biventer cervicis) nerve-muscle preparations. The venom (5 and 10 micro g/ml) produced @entity4094 (85% in 36.8+/-2.0min, mean+/-SEM, n=5, and 18+/-0.6min, n=3, p<0.01, respectively) in the @entity35 preparation. That the phospholipase A(2) (PLA(2)) activity of the venom is involved in this effect was evaluated by inhibiting this enzyme with @entity3349 . This resulted in significantly (p<0.01) increasing the time required for 85% blockade with 5 and 10 micro g/ml to 54+/-4.6min (n=3) and 29+/-0.6min (n=3), respectively. In @entity1573 preparations, the venom (5 micro g/ml) produced @entity4094 in 14.0+/-1.8min (n=5). The contractures to exogenous @entity934 were completely inhibited by the venom, whereas those to 134 micro M @entity4338 were partially blocked in @entity1573 preparations (n=4, n=3, respectively). The venom (5 micro g/ml) produced a progressive decrease in the amplitude of miniature end-plate potentials (m.e.p.ps) in the @entity35 hemidiaphragm, but did not alter the resting membrane potential at 5 micro g/ml. @entity1339 (5.8 micro M) immediate and partially reversed the 85% blockade produced by venom (61%, n=3) in @entity35 preparations, as did @entity973 (53 micro M) ( approximately 59%, n=3). The @entity973 and @entity1339 also restored the m.e.p.ps to pre-venom (control) values. In @entity35 preparations, the venom damaged 47%+/-11% and 62.7+/-3.6% of the muscle fibers at concentrations of 5 and 10 micro g/ml, respectively. For venom in which PLA(2) activity was inhibited, the corresponding values were 38+/-11.8% (5 micro g/ml) and 67+/-9.6% (10 micro g/ml). These findings suggest a post-synaptic neurotoxic action for N. n. kaouthia venom, and that inhibiting phospholipase activity of the venom reduces significantly the @entity4094 but not the direct myotoxicity.

Neurotoxic and myotoxic actions of XXXX kaouthia venom on skeletal muscle in vitro.

@entity1 :: ('9606', 'Species') :: ['mammalian'] @entity4094 :: ('MESH:D009468', 'Disease') :: ['neuromuscular blockade', 'neuromuscular block'] @entity3349 :: ('MESH:C006821', 'Chemical') :: ['p-bromophenacyl bromide'] @entity973 :: ('MESH:D015761', 'Chemical') :: ['4-aminopyridine'] @entity1573 :: ('9031', 'Species') :: ['chick'] @entity32766 :: ('35670', 'Species') :: ['Naja naja'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity1339 :: ('MESH:D009388', 'Chemical') :: ['neostigmine', 'Neostigmine'] @entity4338 :: ('CHEBI:32588', 'Chemical') :: ['KCl'] @entity934 :: ('MESH:D000109', 'Chemical') :: ['acetylcholine']
@entity32766 :: (35670,Species) :: ['Naja naja']
