Previous reports of DBA binding to human endometrium have been inconsistent. According to Lee and Damjanov , DBA stained both glandular epithelium and stroma in proliferative endometrium, but Soderstrom found no DBA staining in wax-embedded material, although in frozen sections there was slight staining in both proliferative and secretory phases. Some of this variation in the data may be due to the absence of protease pretreatment of the sections, although it has also been reported that this makes no difference to DBA staining. Despite much variation in reports of DBA binding to proliferative endometrium in the human, most workers are unanimous in describing binding to glands in the secretory phase of the cycle. Implantation occurs at 7-8 days after the LH surge (5.5-6.0 days postovulation), when DBA is just starting to show in an irregular fashion. Once pregnancy is established, DBA and VVA are strongly bound by the glands. buy asthma inhalers
The difference between humans and baboons in DBA binding to the endometrium is dramatic and, given the strong similarities between the two species in terms of endometrial morphology and cyclicity, unexpected. During the late secretory phase in the human, when the gland ep-ithelia are engorged with DBA-positive material, and secretions are present in the lumina, the baboon epithelium has only a thin surface layer of DBA-positive material coating the cells, suggesting that all the accumulated glycan has already been extruded from the cell. DBA-positive luminal secretions at that time are also fairly sparse.