Nitric oxide synthesis inhibition suppresses implantation and decreases cGMP concentration and protein peroxidation.
The effect of Nw-nitro-L-arginine on embryonic implantation and cGMP carbonyl group concentration was assessed at the rat implantation site (IS) and non-implantation site (NIS). The intraluminal administration of 25 microg (2.3 mM) of Nw-nitro-L-arginine inhibited implantation in 34.7% and embryo survival (100%), while in addition, decreasing cGMP concentration both at the site (1664.2 +/- 333.8 pmoles/mg of protein for the control and 1321 +/- 384.3 for those treated), as well as at the NIS (1203.7 +/- 200 to 780.2 +/- 168.5). Carbonyl group concentration was considerably less at the implantation site treated with Nw-nitro-L-arginine than in the control (0.062 +/- 0.012 nmoles/mg of protein and 0.45 +/- 0.1, respectively). Nonetheless, the NIS was not significantly different (0.12 +/- 0.04 and 0.15 +/- 0.05). Our results show that a nitric oxide (NO) dependent system parallel to the formation of cGMP and protein peroxidation products is important at the blastocyst implantation site in order for the endometrium to acquire the necessary properties for an adequate receptivity.
Durán-Reyes
G
G
Unidad de Investigación Médica en Bioquímica, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico DF.
Gómez-Meléndez
M R
MR
Moralí-de la Brena
G
G
Mercado-Pichardo
E
E
Medina-Navarro
R
R
Hicks-Gómez
J J
JJ
D000818:Animals; D000242:Cyclic AMP / Q000096:biosynthesis; D006152:Cyclic GMP / Q000378:metabolism*; D010064:Embryo Implantation / Q000187:drug effects*; D005314:Embryonic and Fetal Development / Q000187:drug effects; D004717:Endometrium / Q000187:drug effects / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D007202:Indicators and Reagents; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D019335:Nitroarginine / Q000494:pharmacology; D010084:Oxidation-Reduction; D010545:Peroxides / Q000378:metabolism; D010659:Phenylhydrazines; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D004791:Enzyme Inhibitors; D007202:Indicators and Reagents; D010545:Peroxides; D010659:Phenylhydrazines; D011506:Proteins; C004787:2,4-dinitrophenylhydrazine; D019335:Nitroarginine; D009569:Nitric Oxide; D000242:Cyclic AMP; D019001:Nitric Oxide Synthase; D006152:Cyclic GMP