Abstract
The effect of hydrocortisone on morphological changes in developing chick embryo was observed by scanning electron microscopy and light microscopy in relation to changes in enzyme activities.
The morphological changes caused by administration of hydrocortisone were remarkable. In the hydrocortisone-dosed 19th day embryonic duodenum, this hormone caused increases in the height and microvillus length ef absorptive epithelial cells, and in the ratio of microvillus length to cell height, up to the normal just hatched 1st day hatched duodenal level. Injections of this hormone also induced precocious increases in maltase and alkaline phosphatase activities.
On the basis of these results, it is considered that hydrocortisone may be one of the important factors regulating normal development in chick embryonic duodenum and may exert a major influence on the growth and maturation of absorptive epithelial cells.
