Immunohistological demonstration of ACTH-like immunoreactivity in the foetal adrenal medulla in the 23rd week of gestation.

Abstract

By an indirect immunofluorescence technique and silver impregnation, cells reacting with anti-1-18 ACTH antiserum were demonstrated in the foetal adrenal medulla only in the 23rd week of gestation. They were not found in the foetal adrenal glands before the 23rd week or after 29th week and after birth. The result was confirmed by immunohistological examination using anti-1-18ACTH rabbit IgG purified by affinity chromatography. No cells in the foetal adrenal medulla in the 23rd week of gestation were stained positively by using anti-beta-MSH and anti-beta-endorphin antisera. This finding suggested, therefore, that the synthetic mechanism of ACTH-like immunoreactivity in the foetal adrenal glands was different from that in the pituitary. In view of the findings that some phaeochromocytoma contained ACTH-like immunoreactivity, the present study suggested that the origin of the phaeochromocytoma congested that the origin of the phaeochromocytoma containing ACTH-like immunoreactivity may be the cells of the foetal adrenal medulla in about the 23rd week of gestation.