Time-related morphological changes of porcine ovarian granulosa cells incubated with urea-EDTA solution

Morphological profiles of porcine granulosa cells incubated with 10 mM Tris-HCl containing 1 M urea and 5 mM EDTA (urea-EDTA solution) were investigated. The percentages of granulosa cells incorporating the dye, trypan blue on incubation with urea-EDTA solution did not change during the initial 30 min. Thereafter, granulosa cells gradually took up the dye throughout the incubation. The amount of protein released from granulosa cells increased dramatically during initial 15 min of incubation, but decreased during the following 15-30 min of incubation. Thereafter, the amount of proteins released from granulosa cells increased gradually again. The releasing profile of 51Cr-bounded substances in granulosa cells increased markedly during the initial 15 min of incubation, and decreased during the next 15 min of incubation. Subsequently the amount of 51Cr released was enhanced. The min of incubation. Subsequently the amount of 51Cr released was enhanced. The plasma membranes of granulosa cells remained intact at 30 min of incubation, although chromatin clusters of granulosa cells disappeared. Thereafter, a number of cells showed signs of degeneration, including broken plasma membrane and cytolysis. The present study revealed that urea-EDTA solution is useful in extracting materials from porcine granulosa cells. The majority of the materials extracted from granulosa cells during the initial 30 min of incubation with urea-EDTA solution is considered to be from the cell surfaces and/or intercellular matrix.