Ramos J C
Acta Physiol Lat Am. 1975;25(4):288-98.
The sensitivity of some electrocortical potentials of rats to topically applied tetrodotoxin (TTX), manganese, lanthanum, calcium, mescaline and strychnine was followed from the age of 6 to 20 days and compared with that of adult animals. Sensitivity to TTX was relatively greater in the younger rats. In contrast, the blocking effect of Mn2+ or La3+ was small initially but increased with age. Similarly, the ability of mescaline or strychnine to give rise to giant spikes (dendritic action potentials) increased with maturation of the brain cortex. Finally, an increase in external calcium concentration depressed cortical potentials in the younger animals and had the usual increase of the mescaline or strychnine spikes in the older rats. It is concluded that the formation of calcium channels in dendritic membranes is part of the maturation process of cortical neurons and possibly related to the learning mechanisms. The depressant action of high external calcium during the first days of life was ascribed to an unspecific reduction in membrane permeability.
从6日龄到20日龄观察了大鼠某些皮层电位对局部应用河豚毒素（TTX）、锰、镧、钙、麦司卡林和士的宁的敏感性，并与成年动物进行了比较。幼龄大鼠对TTX的敏感性相对较高。相反，Mn2+或La3+的阻断作用最初较小，但随年龄增长而增加。同样，麦司卡林或士的宁引发巨大棘波（树突动作电位）的能力随着大脑皮层的成熟而增强。最后，外部钙浓度的增加使幼龄动物的皮层电位降低，并使老龄大鼠的麦司卡林或士的宁棘波出现通常的增加。得出的结论是，树突膜中钙通道的形成是皮层神经元成熟过程的一部分，可能与学习机制有关。出生后最初几天高外部钙的抑制作用归因于膜通透性的非特异性降低。
