Abstract

The Role of Gp91phox NADPH Oxidase during the Gestational Period of Mice

Keiichi Hiramoto, Yurika Yamate and Eisuke F. Sato

Gp91phox NADPH oxidase enzyme was established earlier to play its role in generating reactive oxygen species. In recent studies, gp91phox NADPH oxidase was reported to be involved in the regulation of ovulation and oestrial cycle. However, its mechanism of action during comparatively stressful gestational period ‘gp’ is not known. Current study was designed to investigate the role of gp91phox NADPH oxidase during ‘gp’ by using gp91phox deficient (gp91phox-/-) mice whereas C57BL/6j mice in graviditas served as control. During ‘gp’ period the floating time (akinesia time) in control group was found to be highest on day 6, which gradually decreased towards parturition. Conversely, ingp91phox-/- mice, there was no such recognizable alteration during ‘gp’ as compared to control C57BL/6j mice. In addition, plasma level of adrenocorticotropic hormone (ACTH) was significantly higher on day 6 (gp) in the control mice. Similarly, the level of growth hormone (GH) was also found elevated during ‘gp’ in control mice. On the other side, in thegp91phox-/- mice, no such increase in ACTH or GH levels as compared to C57BL/6j mice was observed. It is worth mentioning that GH levels (gp) ingp91phox-/- mice were found ever lower than those of the control C57BL/6j mice. There were also fewer newborngp91phox-/- mice compared with C57BL/6j mice; interestingly, the number of fetalgp91phox-/- mice did not decrease until after gd 6. Furthermore, the average weight for the newborngp91phox-/- mice was significantly lower than the C57BL/6j mice. The results of the present study deonstrated that gp91phox NADPH oxidase is required during relatively stressful gestational period ‘gp’ and may play a role during fetal differentiation and growth.