The vagina is part of the genitalia and constitutes part of the birth canal. Sperm
is deposited into vagina, and it acts in transport of sperm. Pregnancy is a complex
process involving different physiological changes in the body associated
with hormonal and metabolic alterations that control maternal and fetal
demands. During pregnancy, neuroendocrine cells in rabbit vagina are considered
part of the diffuse neuroendocrine system observed throughout the body.
Giant neuroendocrine cells in rabbit vagina during pregnancy have not been
observed previously. This study detected the presence of giant neuroendocrine
cells in the vagina of the pregnant rabbit. The presence of these cells was demonstrated
with the use of different histological techniques, including hematoxylin
and eosin, PAS, combined Alcian blue-PAS, Crossmon's trichrome, and the
Grimelius silver method. Giant neuroendocrine cells were observed in latepregnancy
intraepithelial sites and on the lamina propria. These cells were characterized
by vacuolated basophilic cytoplasm with PAS- and PAS-AB-positive
granules. Moreover, neuroendocrine cells exhibited an argyrophilic character.
Immunohistochemically, neuroendocrine cells in rabbit vagina during pregnancy
demonstrated positive immunoreactivity to neuron-specific enolase (NSE) with
different intensities, mild immunoreactivity to the vascular endothelial growth
factor (VEGF), and negative immunoreactivity to CD68