ORIGINAL ARTICLE: Bcl‐2 and Bax Expressions in Pre‐Term, Term and Post‐Term Placentas

American Journal Of Reproductive Immunology (Impact Factor: 2.44). 07/2008; 60(2):172 - 178. DOI: 10.1111/j.1600-0897.2008.00609.x


Problem Placental apoptosis-associated protein imbalance might contribute to the pathogenesis of pre- and post-term birth. Therefore, we evaluated the expression and distribution of pro-apoptotic (Bax) and anti-apoptotic (Bcl-2) molecules in term, pre-term and post-term placentas.
Method of study Placental samples were collected from women with term (n = 25), pre-term (n = 7) and post-term (n = 10) deliveries. The expression of Bcl-2 and Bax was assessed by immunochemistry on paraffin-embedded placental specimens.
Results The pattern of immunostaining for Bcl-2 and Bax was the same in all samples, but not the intensity. The Bax/Bcl-2 ratio was higher in both pre-term and post-term placental samples compared with term placentas as a result of intense reactivity for the pro-apoptotic factor, Bax in pre-term and post-term placentas and, for Bcl-2 decrease in pre-term placentas.
Conclusion These findings suggest that different unbalance mechanisms in placental apoptotic-associated protein expressions may be involved in the physiopathology of pre-term and post-term births.

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