Berlind A
Biology Department, Wesleyan University, Middletown, CT 06457, USA.
Comp Biochem Physiol C Toxicol Pharmacol. 2001 Sep;130(1):85-95. doi: 10.1016/s1532-0456(01)00222-8.
Haloperidol (a dopamine D2 blocker in vertebrates) and phentolamine (an alpha-adrenergic blocker) alter the pattern of bursting by the isolated cardiac ganglion of the lobster when perfused at concentrations of 10(-6)-10(-5) mol/l. Both drugs decrease the frequency of bursting and increase burst duration. They are most effective in slowing the ganglion when applied selectively to the anterior ganglionic trunk, the same region of the ganglion where dopamine (DA) and 5-hydroxytryptamine (5HT) are most effective in speeding up bursting. When exogenous monoamine transmitters are applied in the presence of 3x10(-6) mol/l haloperidol, the effect of 5HT, but not of DA, is significantly reduced. At the same concentration, phentolamine does not suppress the actions of DA, 5HT or noradrenaline (NA). Both haloperidol and phentolamine significantly alter the properties of endogenous burst-organizing potentials (driver potentials) generated by motorneurons in the ganglion. It is possible that the effects of these drugs on bursting reflect alteration of endogenous electrical properties of the constituent neurons, rather than receptor antagonism.
氟哌啶醇（脊椎动物中的多巴胺D2受体阻滞剂）和酚妥拉明（一种α-肾上腺素能阻滞剂）在以10⁻⁶ - 10⁻⁵摩尔/升的浓度灌注时，会改变龙虾离体心脏神经节的爆发模式。两种药物都会降低爆发频率并增加爆发持续时间。当选择性地应用于神经节前干时，它们在减慢神经节活动方面最为有效，神经节前干是神经节中多巴胺（DA）和5-羟色胺（5HT）加速爆发最有效的相同区域。当在3×10⁻⁶摩尔/升氟哌啶醇存在的情况下应用外源性单胺递质时，5HT的作用会显著降低，但DA的作用不会。在相同浓度下，酚妥拉明不会抑制DA、5HT或去甲肾上腺素（NA）的作用。氟哌啶醇和酚妥拉明都会显著改变神经节中运动神经元产生的内源性爆发组织电位（驱动电位）的特性。这些药物对爆发的影响可能反映了组成神经元内源性电特性的改变，而不是受体拮抗作用。
