The OF-1 mice and Wistar rats from the day of birth [postnatal day (P)0] to adulthood (P60) (obtained from the Animal House Facility of the School of Medicine of the University of Castilla-La Mancha) were used for histoblots, and light and electron microscopy immunohistochemical analyses. The animals were housed on a 12 h light/dark cycle, with food and water available ad libitum. The care and handling of the animals prior to and during the experimental procedures followed Spanish and European Union regulations, and were approved by the Animal Care and Use Committee of the institution. For each developmental stage, the animals used were from different litters.
