Fertility and Sterility Nitric oxide synthesis in human nonpregnant myometrium and uterine myomas  Roberta Favini, M.D., Elisabetta Aldieri, Ph.D., Alberto Revelli, M.D., Amalia Bosia, M.D., Marco Massobrio, M.D., Dario Ghigo, M.D.  Fertility and Sterility  Volume 79, Pages 749-753 (March 2003) DOI: 10.1016/S0015-0282(02)04825-2

FIGURE 1 Nitric oxide synthase activity in myometrium and myoma biopsy samples from 21 patients. Enzyme activity was measured as the ability of the homogenate to convert l-arginine in nitrite and citrulline. Favini. NO synthesis in human myometrium. Fertil Steril 2003. Fertility and Sterility 2003 79, 749-753DOI: (10.1016/S0015-0282(02)04825-2)

FIGURE 2 Nitrite levels in the extracellular medium of smooth-muscle cells cultured from myometrium or myoma of six patients. Cells were grown to confluence, at which point the supernatant was replaced by fresh medium. After 24 hours of incubation in the absence (Control) or presence of 15 ng/mL of progesterone (P) or 30 ng/mL of β-estradiol (E), supernatant was checked for nitrite levels. * = P<.05 vs. myometrium; ** = P<.01 vs. myometrium. Favini. NO synthesis in human myometrium. Fertil Steril 2003. Fertility and Sterility 2003 79, 749-753DOI: (10.1016/S0015-0282(02)04825-2)