Search results for "Rate of rise"
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Ca-abh�ngige Membranpotential�nderungen am Herzen und ihre Bedeutung f�r die elektro-mechanische Kopplung. Versuche mit Tetrodotoxin in Na-haltigen L…
1969
1. Tetrodotoxin (TTX), at a concentration of less than 10−6 g/ml, had no effect on membrane potential and contraction of isolated, thin ventricular trabeculae of sheep and calf hearts. 10−6 to 2 × 10−5 g/ml TTX decreased the rate of rise, over-shoot, and duration (phase of 90% repolarisation) of the action potential and the amplitude of contraction, without change in the resting potential and the plateau (20% repolarisation phase) of the action potential. Excitation block regularly occurred only with 10−5 to 2×10−5 g/ml TTX. 2. In a solution containing Na and TTX (5×10−6-2×10−5 g/ml) graded depolarisation was possible if the preparations were stimulated by square wave pulses of 500 msec dur…
Wirkung und Wechselwirkung von Theophyllin und Chinin auf die neuromuskuläre Übertragung und die elektromechanische Kopplung am M. gastrocnemius
1982
It has been reported that theophylline improves the effect of quinine in relieving patients from nocturnal muscle cramps. We therefore examined the actions and interactions of quinine and theophylline on mechanical and electrical properties of the rabbit’s N. ischiadicus — M. gastrocnemius nerve-muscle preperation in situ. Maximal tension, rate of rise of tension, contraction time, relaxation time and latency of single maximal twitch, evoked by electrical stimulation of N. ischiadicus were measured before and after i.p. or iv. application of therapeutic doses of quinine and theophylline given alone or in combination. In addition, changes of conduction velocities of action potentials of the …