Kovacs K, Horvath E, Bilbao J M
Acta Anat (Basel). 1975;93(2):249-56. doi: 10.1159/000144485.
Twelve nontumorous adenohypophyses and 36 various pituitary adenomas, removed by surgery, have been investigated by electron microscopy in order to shed some light on annulate lamellae, primarily on their ultrastructural features, incidence, origin, fate and functional significance. No annulate lamellae were found in the nontumorous adenohypophyses and in 33 pituitary adenomas. They were, however, detected in two adenomas consisting of undifferentiated cells and one adenoma composed of sparsely granulated prolactin cells indicating that these unique membrane configurations cannot be regarded as an exceedingly rare finding and, furthermore, that they may be disclosed not only in undifferentiated but occasionally in highly differentiated cells. Annulate lamellae may arise from endoplasmic reticulum and/or nuclear envelope and consist of arrays of smooth walled double membrane sheets exhibiting regularly spaced interruptions as well as continuities with the endoplasmic reticulum. No relationship was established between annulate lamellae and adenohypophysial secretory activity. Our findings seem to be consistent with the view that annulate lamellae are present in those cells which have the tendency to proliferate.
为了阐明环状片层，主要是其超微结构特征、发生率、起源、命运及功能意义，对手术切除的12个非肿瘤性腺垂体和36个不同类型的垂体腺瘤进行了电子显微镜研究。在非肿瘤性腺垂体和33个垂体腺瘤中未发现环状片层。然而，在两个由未分化细胞组成的腺瘤和一个由颗粒稀少的催乳素细胞组成的腺瘤中检测到了环状片层，这表明这些独特的膜结构并非极为罕见的发现，而且，它们不仅可能出现在未分化细胞中，偶尔也会出现在高度分化的细胞中。环状片层可能起源于内质网和/或核膜，由光滑壁的双膜片阵列组成，这些双膜片呈现出规则间隔的中断以及与内质网的连续性。环状片层与腺垂体分泌活动之间未建立联系。我们的发现似乎与以下观点一致，即环状片层存在于那些有增殖倾向的细胞中。
