[Cyto-immunological studies of the gonadotropic cells of the human fetus].

The immunicytological analysis of PAE fixed semi-thin sections of pituitary cells (of human fetuses aged 6 to 26 weeks) using immunesera directed against the human total glycoproteic hormones, HCG, LH, FSH and TSH or made specific for the LH, FSH, and TSH beta subunits shows: -- the presence up to the 12th week of only the subunit of the glycoproteic hormones revealed indifférently by our anti total hormones immunesera; -- the apparition of the betaTSH subunits at the 13th week, characterizing the differentiation of the thyrotrophs; -- the apparition of betaLH and betaFSH subunits on the one and same gonadotropic cell population at the 15th week.