Mestres P
Experientia. 1976 Oct 15;32(10):1329-31. doi: 10.1007/BF01953122.
The number of SEC in the hypothalamus of the rat change during the ovarian cycle (5-8 cells in oestrus, 100 cells in dioestrus per ventricular surface). The changes in the number as well the morphology of the SEC support the hypothesis that they are of mesenchymal nature.