The evoked reversal characteristics of atracurium were studied in 21 patients using edrophonium or neostigmine and a train-of-four pattern of stimulation. Reversal of residual atracurium -induced neuromuscular blockade was significantly more rapid using edrophonium compared with neostigmine. The ratio of the fourth twitch in the train-of-four to the first twitch--the T4 ratio--was significantly...

In vitro studies using the rat phrenic nerve-hemidiaphragm preparation were performed to investigate the effects of diazepam and three of its metabolites on indirectly evoked twitch tension. Diazepam, desmethyldiazepam and temazepam alone caused an increase in twitch tension in lower concentrations, followed by complete depression in higher concentrations. Oxazepam did not cause an initial incr...

TRANSCUTANEOUS ELECTRICAL and, later, magnetic twitch stimulation of the femoral nerve have been introduced to quantify quadriceps muscle function. These techniques were developed in an attempt to overcome the drawbacks of measurements of maximal voluntary contraction force and tetanic stimulations. Maximal voluntary contractions are motivation-dependent maneuvers that can be marred by submaxim...

Voluntary activation. A muscle is activated voluntarily when force is produced by the recruitment of motoneurons through increased descending drive from the motor cortex. This activation is usually deliberate and is accompanied by a sense of effort. There are many other influences on motoneurons at rest and during voluntary contractions that may alter the response of motoneurons to descending d...

Effects of 5 kinds of fluorides on the twitch of the sartorius muscle of the bull frog were investigated. All of the fluorides (0.1-2.0 mM) enhanced the twitch evoked by nerve stimulation. The extents of enhancement at 2.0 mM were in the order: stannous fluoride much greater than potassium fluoride greater than sodium silico fluoride greater than sodium fluoride greater than diammine silver flu...

effects of venom from black scorpion androctonus crasicuda (ac) were determined on isolated chick biventer cervices nerve-muscle and mouse hemidiaphragm preparations using twitch tension method. the isolated nerves were stimulated by electrical stimulator and response to each stimulus was recorded. the venom mainly acted prejunctionally to facilitate neuromuscular activity due to an increase in...