It has been reported that apoptosis plays an essential role in controlling
the physiological cell kinetics in the human and rodent endometrium but thi
s type of death has never been studied in the porcine endometrium. The aim
of this study was to investigate the apoptotic cell death in the porcine en
dometrium during the middle (Days 9-11) and late (Day 13) luteal phase, dur
ing the luteolysis (Day 15) and early follicular phase (Days 17-19) of the
oestrous cycle. Apoptotic cells were identified by in situ DNA 3'-end label
ling method. It was revealed that the greatest number of apoptotic cells in
the luminal and glandular epithelium was found on Days 17-19 and on Day 15
of the oestrous cycle, respectively. In the stroma, the greatest number of
these cells was found on Days 9-11. Our data have shown that in the porcin
e endometrium, both epithelial and stromal cells undergo apoptosis and that
the number of apoptotic cells varies depending on the phase of the oestrou
s cycle.