Effect of hydrocortisone on the development of embryonic chick duodenum--transmission electron microscope studies

The effect of hydrocortisone on morphological changes in developing chick embryo was observed by transmission electron microscopy and immunohistologically with antiserum of actin. The morphological changes were more remarkable in the hydrocortisone-dosed 19th day embryonic duodenum. This hormone caused increase in the height and length of microvilli in absorptive epithelial cells. The development of organella such as Mitochondria, Golgi's apparatus and endoplasmic reticulum in the absorptive epithelial cells were enhanced. Injection of this hormone also induced an increase in microfilamentus bundles in the microvilli of absorptive epithelial cells. These morphological features of hydrocortisone-dosed 19th day embryonic duodenum indicated similar ones to the chicken at the stage of normal just hatching or 1st day after hatching. These results strongly support the previous suggestion that hydrocortisone may be one of the important factors regulating normal development in chick embryonic duodenum and may exert a major influence on the rapid growth and maturation of absorptive epithelial cells.