(1980) demonstrated that although cypermethrin and bioresmethrin did not potentiate veratridine-induced 22[Na.sup.+] uptake in neuroblastoma cells, they did produce a concentration-dependent reduction of 22[Na.sup.+] uptake induced by a combination of veratridine and kadethrin.
These data are consistent with results in neuroblastoma cells showing that cw-permethrin and bioresmethrin inhibited 22[Na.sup.+] influx induced by a combination of veratridine and kadethrin (Jacques et al.
Berberine, palmatine and jatrorrhizine, the components of RC, all inhibited CA secretion induced by ACh, veratridine
and/or 56 mM [K.sup.+] (Figs.
The present study further characterizes these major processes of cholinergic function, by analyzing the time-course of ACh release and Ch uptake and by comparing the effect of two secretagogues, KCl and veratridine, in pinched-off nerve terminals (synaptosomes) from cuttlefish optic lobes.
After incubation for several minutes at room temperature, the depolarization stimulus was applied by addition of KCl (final concentration 40 mmol [1.sup.-1]) or veratridine (final concentration 40 [micro]mol [1.sup.-1]).
In contrast, addition of veratridine produced, after a short latency, a moderate and slow enhancement of light emission (Fig.
To further evaluate the effects of high potassium concentration and of veratridine on the neurotransmitter release, we analyzed the cumulative release profiles.
In the present study, we evaluated this possibility by measuring light emission upon stimulation with KCI or veratridine of synaptosomes pretreated with 47 [micro]mol [1.sup.-1] of echothiophate iodide, an acetylcholinesterase inhibitor.
Honerjager, P., Reiter, M.: The relation between the effects of veratridine on action potential and contraction in mammalian ventricular myocardium.
Pang, D.C., Sperelakis, N.: Veratridine stimulation of calcium uptake by chick embryonic heart cells in culture.
Patmore, L., Duncan, G.P., Spedding, M.: The effects of calcium antagonist on calcium overload contractures in embryonic chick myocytes induced by ouabain and veratridine. Br.
Sperelakis, N., Pappano, A.J.: Increase in [P.sub.Na] and [P.sub.K] of cultured heart cells produced by veratridine, J.