Microtubules in Thyroidectomy Cells of the Rat Anterior Pituitary Gland 1

Abstract

Summary

Microtubules were successfully illustrated in thyrotrophs and thyroidectomy cells of rat pituitary glands. In contrast, microfilaments were mostly seen in the nonglandular follicular cells. Numerous microtubules were observed in the early stages of development of the thyroidectomy cell. In thyroidectomy cells microtubules were located in close proximity to mitochondria, endoplasmic reticula, secretory granules, and membranes of Golgi complexes. Consequently, it is suggested that microtubules may play a role in degranulation or other processes associated with the hypersecretory state.

Fig. 1. An example of a thyroidectomy cell thought to represent an early stage in the cellular modification which follows thyroidectomy. Arrows indicate microtubules (X37,000).

Fig. 2. Microtubules (arrows) located among swollen endoplasmic reticula and secretory granules of a thyroidectomy cell. In the lower right portion of the figure is a cytoplasmic process of a follicular cell. This cell process contains numerous microfilaments as well as microtubules (X 45,000).

Fig. 3. Microtubules (arrows) in close proximity to two mitochondria of a thyroidectomy cell (X 55,000).

Fig. 4. Microtubules (arrows) in the vicinity of the Golgi complex of a thyroidectomy cell. G: Golgi zone M: Mitochondria. (X 44,000).