Role of Endocytosis in Cellular Uptake of Sex Steroids

  title={Role of Endocytosis in Cellular Uptake of Sex Steroids},
  author={Annette Hammes and Thomas Kjaergaard Andreassen and Robert Spoelgen and Jens Raila and Norbert Hubner and Herbert Schulz and Jochen H Metzger and Florian J. Schweigert and Peter B. Luppa and Anders Nykjaer and Thomas E. Willnow},
Androgens and estrogens are transported bound to the sex hormone binding globulin (SHBG). SHBG is believed to keep sex steroids inactive and to control the amount of free hormones that enter cells by passive diffusion. Contrary to the free hormone hypothesis, we demonstrate that megalin, an endocytic receptor in reproductive tissues, acts as a pathway for cellular uptake of biologically active androgens and estrogens bound to SHBG. In line with this function, lack of receptor expression in… CONTINUE READING