Liu Y, Jia W, Strosberg A D, Cynader M
Department of Ophthalmology, University of British Columbia, Vancouver, Canada.
Brain Res. 1993 Dec 31;632(1-2):274-86. doi: 10.1016/0006-8993(93)91162-l.
The developmental pattern and laminar distribution of beta 1 and beta 2 adrenergic receptor subtypes were studied in cat visual cortex with autoradiography using [125I]iodocyanopindolol as a ligand and also with immunocytochemistry using a monoclonal antibody directed against beta adrenergic receptors. In the primary visual cortex of adult cats, the laminar distributions of both beta 1 and beta 2 adrenergic receptors revealed by autoradiography were very similar, with concentrations in layers I, II, III and VI. In young kittens (postnatal days 1 and 10), fewer beta adrenergic receptors were present, and they were concentrated in the deep cortical layers (V-VI) and subcortical white matter. Between postnatal days 15 and 40, beta adrenergic receptors increased in density more quickly in the superficial layers than they did in the deep and middle cortical layers. By postnatal day 40, the adult pattern was achieved, with two bands of intense binding in the superficial and deep cortical layers and a lower density in layer IV. Immunocytochemical techniques applied to adult cat cortex showed that beta adrenergic receptor-like immunoreactivity was found in different populations of neurons and glial cells. The immunoreactive neural cells were most dense in layers II, III and VI. About 50% of these immunoreactive neural cells were glial cells, primarily astrocytes. Immunoreactive pyramidal cells were mostly located in layers III and V. In layer IV, many stellate cells were stained. Immunoreactive astrocytes in the subplate and white matter progressively increased in number during development until adulthood. The pattern of laminar distribution and the developmental process was not affected by interrupting noradrenergic innervation from locus coeruleus either before or after the critical period. However, when visual input was interrupted by lesions of the lateral geniculate nucleus in young kittens (postnatal day 10), the density of both beta adrenergic receptor subtypes decreased significantly in the deep cortical layers. Lateral geniculate nucleus lesions in adult cats resulted in a pronounced decrease in beta adrenergic receptor density in layer IV.
利用放射自显影技术，以[125I]碘氰吲哚洛尔作为配体，以及利用针对β肾上腺素能受体的单克隆抗体进行免疫细胞化学方法，研究了猫视觉皮层中β1和β2肾上腺素能受体亚型的发育模式和分层分布。在成年猫的初级视觉皮层中，放射自显影显示的β1和β2肾上腺素能受体的分层分布非常相似，在I、II、III和VI层有浓度峰值。在幼小猫（出生后第1天和第10天）中，β肾上腺素能受体较少，且集中在皮质深层（V-VI层）和皮质下白质中。在出生后第15天至40天之间，浅层中β肾上腺素能受体密度的增加速度比深层和中层皮质更快。到出生后第40天，达到成年模式，在浅层和深层皮质层有两条强烈结合带，而IV层密度较低。应用于成年猫皮层的免疫细胞化学技术表明，在不同的神经元和胶质细胞群体中发现了β肾上腺素能受体样免疫反应性。免疫反应性神经细胞在II、III和VI层最为密集。这些免疫反应性神经细胞中约50%是胶质细胞，主要是星形胶质细胞。免疫反应性锥体细胞大多位于III和V层。在IV层，许多星形细胞被染色。在发育过程直至成年期，板下和白质中的免疫反应性星形胶质细胞数量逐渐增加。分层分布模式和发育过程在关键期之前或之后中断蓝斑去甲肾上腺素能神经支配时均不受影响。然而，当幼小猫（出生后第10天）外侧膝状体核受损导致视觉输入中断时，皮质深层中两种β肾上腺素能受体亚型的密度均显著降低。成年猫外侧膝状体核损伤导致IV层β肾上腺素能受体密度明显降低。
