ウサギ摘出回腸における傍血管神経刺激,Nicotine及びTyramineの弛緩機序,特にAcetylcholine及びCalciumとの関連

抄録

1) Relaxations of periarterial nerve stimulation, nicotine (in the presence of atropine), tyramine, acetylcholine (in the presence of atropine and eserine) and calcium in the isolated rabbit's ileum have been investigated from the standpoint of catecholamine release phenomenon.
2) Periarterial nerve stimulation, nicotine and acetylcholine produce catecholamine release through mobilization of calcium. This calcium mobilization could be due to depolarization of sympathetic nerve ending membrane. Tyramine releases catecholamine by exchange reaction without mobilization of calcium.
3) The hypothesis of Burn et al. suggesting that catecholamine release by the sympathetic nerve stimulation is produced via the release of acetylcholine within this nerve cannot be accepted.
4) Nicotine releases catecholamine chiefly through the action of acetylcholine released from the parasympathetic nerve ending by the stimulation of parasympathetic ganglion. 5) Periarterial nerve stimulation, nicotine, acetylcholine and calcium release catecholamine from the same catecholamine store, while tyramine releases catecholamine from other stores.