Possible Interaction: Tubocurarine and Hexamethonium

“The positive inotropic effects of all three drugs are blocked by ganghionic blocking agents hexamethonium , tetracthmylammonium and d tubocurarine).”

“High DMPP concentrations (10 and 30 μM) enhanced the evoked release only when the pretreatment interval was reduced from 15 min to 20 s Tubocurarine and hexamethonium concentration-dependently inhibited the end-organ response.”

“These nicotinic actions were completely reversed by dihydro-beta-erythroidine (DH-beta-E) or hexamethonium and reduced by D-tubocurarine.”

“Increasing the concentration of hexamethonium produced potentiation of the neuromuscular blocking effect, this being greater with tubocurarine than with either pancuronium or alcuronium.”

“Low concentrations of hexamethonium antagonized the neuromuscular blocking effect of all three neuromuscular blocking drugs, less with tubocurarine than with the other two.”

“The effectiveness of hexamethonium in blocking end‐plate currents was reduced in the presence of (+)‐tubocurarine , indicating that hexamethonium has a competitive blocking action on the receptors.”

“1 The ability of hexamethonium (C6) to reverse the neuromuscular blocking action of tubocurarine (Tc) has been reinvestigated at the voltage clamped endplate of the omohyoid muscle of rat.”

“At present, it is shown that atropine and tubocurarine do not inhibit this activity of acetylcholine, but that it is inhibited by blocking the N1 receptor with hexamethonium.”

“ Tubocurarine and hexamethonium presumably competitively antagonized acetylcholine (pA2 values, 7·3 and 5·8); lobeline was a noncompetitive antagonist (pD′2 value, 6·4).”

“Equilibration with hexamethonium reduces the fraction excluded by tubocurarine and the transmitter now competes with hexamethonium for more receptors and produces a larger response.”

“At a [3H]acetyl-α-bungarotoxin … 0.875 µm, 1 µm d-tubocurarine inhibited binding 52%; 1 µm acetylcholine, 30%; 1 µm choline, 0%; 1 µm carbachol, … µm atropine, 0%; 1 mum gallamine, 33%; 1 µm decamethonium, 44%; 1 µm hexamethonium , 16%; 1 µm propanpheline, … 1 µm serotonin, 0%.”