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 wrote in his spare time during the "Blood Sugar Sex Magik" sessions. Frusciante began working on final cuts of the songs he had been writing, and producing them at his home in mid-1992. The production process, however, became hampered by his increasingly severe addiction to heroin. "Usually Just a T-Shirt" was recorded in the order it appears, with the final tracks being recorded shortly prior to Frusciante's departure from the Chili Peppers. Frusciante's use of heroin and cocaine became more extreme during the final stages of recording in late 1993; he began viewing drugs as the only way to "make