JOURNAL ARTICLE

Immunohistochemical localization of inducible and endothelial nitric oxide synthase in porcine ovaries and effects of NO on antrum formation and oocyte meiotic maturation

Yong Tao, Zhuo Fu, Meijia Zhang, Guoliang Xia, Jie Yang, Huirong Xie
Molecular and Cellular Endocrinology 2004 July 30, 222 (1): 93-103
15249129
The present study is to investigate the immunolocalization of endothelial and inducible nitric oxide synthase (eNOS, iNOS) in porcine ovary and the effect of nitric oxide (NO) on antrum formation and oocyte meiotic resumption. In Experiment 1, preantral follicles (250-300 microm in diameter) were cultured in 0 (Control), 0.1, 0.3, 0.5 or 1 mM sodium nitroprusside (SNP), a NO donor. In Experiment 2, the cumulus-oocyte complexes (COCs) aspirated from medium follicles (3-6 mm in diameter) were incubated in 0.1mM SNP or two inhibitors for NOS, 10 mM aminoguanidine bicarbonate salt (AG) or 1 mM Nomega-nitro-l-arginine methyl ester (L-NAME), alone or concomitantly. In Experiment 3, ovarian tissues, corpus luteum (CL), corpus albican (CA) and COCs from small (1-2 mm in diameter), medium (3-6 mm) and large follicles (7-10 mm) were isolated, rinsed, fixed, paraffin embedded and stained by the conventional avidin-biotin complex method for the detection of eNOS and iNOS production. The results showed that 0.1mM SNP had no effect on antrum formation (P > 0.05) while 0.3, 0.5 or 1 mM significantly inhibited the antrum formation (P < 0.05). AG markedly inhibited porcine oocyte meiotic resumption (P < 0.05) while L-NAME inhibited first polar body (PB1) extrusion (P < 0.05). The immunoreactivity of eNOS in early antral follicles was restricted to oocyte and it increased from small, medium to large follicle-enclosed oocytes. Cumulus cells from large follicles showed weak eNOS immunoreactivity but those from small or medium follicles not. In CL, eNOS-positive staining was shown in granulosa lutein cells. In CA, it was in some parenchymal cells. In contrast, no immunoreactivity for iNOS was found in primordial, early antral follicle or the COCs aspirated from small and medium follicles. The large follicle-enclosed oocyte showed weak immunoreactivity. In CL, some granulosa lutein cells showed iNOS-positive cytoplasm. Such immunostaining was not found in CA. The results demonstrate that porcine ovaries have distinct cell-specific expression of both eNOS and iNOS, and that NO derived from both NOS is actively involved in meiotic resumption. Nitric oxide is not involved in the antrum formation of preantral follicles but exogenous NO inhibits the antrum formation. Endothelial nitric oxide synthase and inducible nitric oxide synthase might be differently functional in CL development and regression.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
15249129
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"