Transglutaminase(TGase) is a calcium dependent enzyme that catalyse the acyl transfer reaction forming ε-(γ-glutamyl)-lysine cross linkage.The major known effect of transglutaminase is its important role in the programmed cell death manifested
in
the
granular layer of the skin and acidophilic bodies in the inflammatory disease of the liver. Although the enzyme is known to be expressed in various tissues and conditions, is expression in the placenta tissue related to the pregnancy and delivery
mechanism has not been clearly demonstrated. Using polyclonal antibodies against cytosolic TGase C, the distribution pattern of these enzyme were studied in the tissues of pregnant rat particularly in the uterus, oviduct and placenta. The
presence
of
TGasc was detected immunohistochemically by avidin biotin peroxidase method.
In the uterus the surface epithelium of endometrium showed strong positivity for TGase, and otherwise unchanged. In the endometrial gland and stroma TGase was weakly positive. From the 8th day, TGase was detected in central zone of decidual
tissue.
In
the placenta, TGase was positive in the glycogen cells and giant trophoblasts of basal plate and well formed labyrinth. Decidual tissue shows the most remarkable changes, expressing TGase. At the early stage its activity shows from the fetal side
showing strong staining in the one half followed by full thickness positivity and in the term TGase activity is localized in the maternal side of the placenta. In the ovary TGase was positive only in the eggplasm and lutein cells. In the oviduct
TGase
was expressed weakly in the surface epithelium. Postpartum uterus is basically the same pattern of TGase expression as the nonpregnant uterus.
In conclusion, tranglutaminase expression is changed along with the gestation date and its changing pattern highly suggests that transglutaminase may play a major role in the uterus during delivery, inducing the programmed cell death of decidual
tissue.
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