We suggest that cessation of plasma flow leads to the observed synchronous apoptosis of VECs due to plasma survival factor deprivation. We have chosen to test a number of aspects of this model using a vital cell imaging system. Comparison of vital images with histological preparations of the PM have indicated that VEC apoptosis causes either a capillary narrowing or blockage and that synchronous apoptosis occurs after a block to plasma flow has occurred. These observations largely confirm the proposed model and show that there is an inverse relationship between flow status and VEC death. Our future work will be aimed at determining the molecular signalling events leading to developmental capillary regression.
Macrophages induce apoptosis in normal cells in vivo.
Lens induction by Pax-6 in Xenopus laevis . A highly conserved lens transcriptional control element from the Pax-6 gene. Pax6 induces ectopic eyes in a vertebrate. Endogenous and ectopic glands are induced by FGF-10.