A new approach to three-dimensional reconstructed imaging of hormone-secreting cells and their microvessel environments in rat pituitary glands by confocal laser scanning microscopy

There has been considerable interest in the relationship between hormone-se creting endocrine cells and their microvessels in human pituitary gland. Ho wever, microcirculatory networks have rarely been studied in three dimensio ns (3D). This study was designed to visualize and to reveal the relationshi p between hormone-secreting endocrine cells and their microvessel environme nt in 3D, using rat pituitary glands under various (hyper/hypo) experimenta l conditions by confocal laser scanning microscopy (CLSM). Female adult Wis tar rats were used after bilateral adrenalectomy or ACTH administration for 2 weeks. Clear 3D reconstructed images of ACTH cells, the microvessel netw ork and counterstained nuclei were obtained at a maximal focus depth of 1 m m by CLSM without any background noise. In the hyperfunctional state, slend er cytoplasmic processes of hypertrophic stellate ACTH cells frequently ext ended to the microvessels. In the hypofunctional state, ACTH cells appeared atrophic and round with scanty cytoplasm, and cytoplasmic adhesions to mic rovessel network patterns were inconspicuous. Therefore, 3D reconstructed i maging by CLSM is a useful technique with which to investigate the microves sel environment of hormone-secreting cells and has the potential to reveal dynamic hormone-secreting pathways.