[Kinetics of protein synthesis in the human granulosa lutein cell during pregnancy as revealed by electron microscopic autoradiography of 3H-leucine].
Kinetics of protein synthesis in the human granulosa lutein cell during pregnancy were investigated using the electron microscopic autoradiography of 3H-leucine. The corpus luteum of early pregnancy was chased at 10 and 30 min, 1, 3, 6, 12, 24 and 48 h after pulse labelling (10 min) with 100 microCi of 3H-leucine. Although the whole silver grains were very few at 10 min postpulse, silver grains were localized mainly over the rough endoplasmic reticulum (r-ER, 34.3%) and there were no silver grains over the smooth endoplasmic reticulum (s-ER). At 30 min postpulse, the ratio of the grain number to r-ER is decreased (18.7%) and silver grains begin to appear over the s-ER (5.4%). The total number of silver grains over the cell increases with the lapse of time, the ratio of the grain number over the r-ER slightly increases and then decreases afterwards, while that over the s-ER continues to increase gradually. From these facts, it is felt that some protein synthesized on the r-ER might be transported to the s-ER in the human granulosa lutein cell during pregnancy showing steroidogenic activity.
D001345:Autoradiography; D003338:Corpus Luteum / Q000378:metabolism*; D005260:Female; D006801:Humans; D007700:Kinetics; D008184:Luteal Cells / Q000378:metabolism* / Q000648:ultrastructure; D008928:Mitochondria / Q000648:ultrastructure; D011247:Pregnancy; D014176:Protein Biosynthesis; D011858:Radiographic Magnification