The Production of a Gonadotrophic Substance (Prolan) by Placental Cells in Tissue Culture

Human Hormone Production in vitro

“…The association between drug-induced hypertrophy of smooth-surfaced endoplasmic reticulum (SER) in hepatocytes and increased activities of hepatic drugmetabolizing enzymes is well documented (1). Both in the rat (2) and in man (3) Thirty-two male Sprague-Dawley rats, initially weighing about 250 g, were studied.…”

Electron Microscopic Study of the Human Trophoblast in Culture

“…Many studies have been carried out on the morphological identification of human trophoblast in tissue culture. Gey, Seegar and Hellman (1938) classified the cells in explant culture of human placenta into three basic types and identified the large epithelial cells with clear cytoplasm and round delicate nucleus as Langhans' type cells which revealed predominant outgrowth after two weeks of cultivation with human chorionic gonadotropin (HCG) producing activity in culture medium, though the possibility for releasing HCG from the explant itself could not be eliminated. Thiede (1960 and, also attempted to identify the function with his three basic cell type in monolayer culture, which could eliminate the explant as the sourse of HCG, but the cytologic and cytochemical studies failed to correlate these types with the histological prototypes of the placenta, but the definite existence of HCG in culture medium proved that at least one of these cell types was originated from trophoblast and kept the special function of HCG production.…”

“…On the other hand, studies on human trophoblast using tissue culture techniques have been carried out by some investigators (Gey, Seegar and Hellman, 1938, Soma, Ehrmann and Hertig, 1964, Thied, 1960, and Thiede and Rudolph, 1961. Notake et al (1965) revealed three types of outgrowth pattern and changes in process of aging, and also Patillo et al (1968) succeeded in continuous culture of human choriocarcinoma transplanted to the hamster cheek pouch.…”

Redundancy of washing in the preparation of biological specimens for transmission electron microscopy

“…6) may represent the product of protein synthesis on the ribosomes of the reticulum. Material of similar density occurs in the swellings of the perinuclear cisterna and may represent precursors of human chorionic gonadotrophin which is one of the major products of the trophoblast in culture (Gey, Seegar & Hellman, 1938;Lake & Borland, 1970). The nuclear envelope exhibits a thickened internal lamina (Fig.…”