Mammary gland gestation, serum progesterone remains at a stably high concentration so signaling through its receptor is continuously activated. As one of the transcribed genes, Wnts secreted from mammary epithelial cells act paracrinely to induce more neighboring cells' branching. When the lactiferous duct tree is almost ready, "leaves" alveoli are differentiated from luminal epithelial cells and added at the end of each branch. In late pregnancy and for the first few days after giving birth, colostrum is secreted. Milk secretion (lactation) begins a few days later due to reduction in circulating progesterone and the presence of another important hormone prolactin, which mediates
Niandra LaDes and Usually Just a T-Shirt LaDes and Usually Just a T-Shirt" was initially previewed by "Billboard" magazine, who said that "Chili Peppers fans might be daunted by the album's elusive experimentalism." A representative of American Recordings did not foresee the album as being viable in any mainstream music stores, and some retailers went as far as to ban it from being sold. After the album was released, Frusciante played three small performances, and participated in a few magazine interviews to promote the album, explaining in one interview that people would only be able to understand his work if "their heads are capable of tripping out."