Abstract:
Using anti-neurofilament H non-phosphorylated antibodies (SMI-32) as markers for the neuronal maturation level and Y channel responsible for motion processing, we investigated early postnatal development of the primary visual areas 17 and 18 in cats aged 0, 10, 14, and 34 days and in adults. Two analyzed parameters of SMI-32-immunolabeling were used: the total proportion of SMI-32-labeling and the density of labeled neurons. (i) The developmental time course of the total proportion of SMI-32-labeling shows the general increase in the accumulation of heavy-chain neurofilaments. This parameter showed a different time course for cortical layer development; the maximal increment in the total labeling in layer V occurred between the second and fifth postnatal weeks and in layers II-III and VI after the fifth postnatal week. In addition, the delay in accumulation of SMI-32-labeling was shown in layer V of the area 17 periphery representation during the first two postnatal weeks. (ii) The density of SMI-32-labeled neurons decreased in all layers of area 18, but was increased, decreased, or had a transient peak in layers II-III, V, and VI of area 17, respectively. The transient peak is in good correspondence with some transient neurochemical features previously revealed for different classes of cortical and thalamic neurons and reflects the time course of the early development of the thalamocortical circuitry. Some similarities between the time courses for the development of SMI-32-labeling in areas 17/18 and in A- and C-laminae of the LGNd allow us to propose heterochronous postnatal development of two Y sub-channels.
摘要:
使用抗神经丝H非磷酸化抗体(SMI-32)作为神经元成熟水平和负责运动处理的Y通道的标记,我们调查了年龄在0,10,14和34天的猫和成人中主要视觉区域17和18的出生后早期发育。使用SMI-32免疫标记的两个分析参数:SMI-32标记的总比例和标记的神经元的密度。(i)SMI-32标记的总比例的发育时间过程表明,重链神经丝的积累普遍增加。该参数显示皮质层发育的时间过程不同;第V层中总标记的最大增加发生在产后第二周和第五周之间以及产后第五周之后的第II-III和VI层中。此外,在出生后的前两周,在区域17外围代表的第V层中显示了SMI-32标记的积累延迟。(ii)SMI-32标记的神经元的密度在区域18的所有层中降低,但增加,减少,或者在II-III层中有一个瞬态峰,V,和区域17的VI。瞬时峰与先前针对不同类别的皮质和丘脑神经元揭示的一些瞬时神经化学特征具有良好的对应关系,并反映了丘脑皮质电路早期发育的时间过程。在17/18区域以及LGNd的A-和C-层发展SMI-32标记的时间过程之间存在一些相似之处,使我们能够提出两个Y子通道的异相出生后发展。