Ca2+/calmodulin-dependent nitric oxide synthase activity in the human cervix carcinoma cell line ME-180

We show here that the human cervix carcinoma cell line ME-180 expresses a constitutive nitric oxide (NO) synthase, as demonstrated by formation of [3H]citrulline and nitrite. The enzyme is dependent on tetrahydrobiopterin, NADPH, flavins and Ca2+/calmodulin. Enzyme activity is located in the cytosol rather than in the membrane fraction and can be inhibited by NG-monomethyl-L-arginine (NMMA). An antiserum to NO synthase purified from porcine cerebellum inhibited the enzyme activity. ME-180 cells released NO, as was shown by stimulation of guanylate cyclase (EC 4.6.1.2) in RFL-6 detector cells; this release was stimulated 8-fold by the Ca2+ ionophore A23187 and 2-fold by increasing the intracellular tetrahydrobiopterin levels with cytokines. This is the first characterization of a Ca2+/calmodulin-dependent NO synthase activity in human epithelial-type tumour cells.

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Ca2+/calmodulin-dependent nitric oxide synthase activity in the human cervix carcinoma cell line ME-180

Biochemical Journal ◽

10.1042/bj2910951c ◽

1993 ◽

Vol 291 (3) ◽

pp. 951-951

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Cell Line ◽

Carcinoma Cell ◽

Carcinoma Cell Line ◽

Cervix Carcinoma ◽

Oxide Synthase ◽

Nitric Oxide Synthase Activity ◽

Human Cervix

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Synthesis, in vitro cytotoxicity activity against the human cervix carcinoma cell line and in silico computational predictions of new 4-arylamino-3-nitrocoumarin analogues

Journal of Molecular Structure ◽

10.1016/j.molstruc.2019.127047 ◽

2020 ◽

Vol 1200 ◽

pp. 127047 ◽

Cited By ~ 4

Author(s):

Ahmed H. Halawa ◽

Essam M. Eliwa ◽

Ahmed A. Hassan ◽

Hesham S. Nassar ◽

R.A. El-Eisawy ◽

...

Keyword(s):

Cell Line ◽

In Silico ◽

Carcinoma Cell ◽

In Vitro Cytotoxicity ◽

Carcinoma Cell Line ◽

Cervix Carcinoma ◽

Cytotoxicity Activity ◽

Computational Predictions ◽

Human Cervix

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Nitric Oxide Synthase Is Deficient in the Aganglionic Colon of Patients With Hirschsprung's Disease

PEDIATRICS ◽

10.1542/peds.93.4.647 ◽

1994 ◽

Vol 93 (4) ◽

pp. 647-651

Author(s):

John F. Bealer ◽

Eileen S. Natuzzi ◽

Cori Buscher ◽

Alan W. Flake ◽

N. Scott Adzick ◽

...

Keyword(s):

Nitric Oxide ◽

Enzyme Activity ◽

Smooth Muscle ◽

Nitric Oxide Synthase ◽

Nicotinamide Adenine Dinucleotide ◽

Hirschsprung's Disease ◽

Hirschsprung’S Disease ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

No Synthase ◽

Oxide Synthase

Objectives. The cause of Hirschsprung's disease is unknown but defects in nonadrenergic, noncholinergic innervation could prevent relaxation of aganglionic colon in patients with this disease. Nonadrenergic, noncholinergic nerves induce relaxation by using nitric oxide synthase to produce the smooth muscle relaxant nitric oxide (NO). In this study we asked whether aganglionic colon in patients with Hirschsprung's disease is deficient in NO synthase-containing nerves. Methodology. Using the tetrazolium blue dye method of demonstrating nicotinamide adenine dinucleotide phosphate-diaphorase enzymes, we examined eight colon specimens (four aganglionic and four ganglionic) from patients with Hirschsprung's disease for the presence of NO synthase. We further quantified NO synthase enzyme activity in these eight specimens by using the [3H]arginine-to-[3H]citrulline conversion assay. Results. The nicotinamide adenine dinucleotide phosphate-diaphorase staining showed that aganglionic colon contained less NO synthase than ganglionic colon. This NO synthase deficiency was located primarily in the nerves of the circular muscle layer of the colon. In addition, there was a striking difference in the NO synthase enzyme activity between aganglionic and ganglionic colon as measured by the [3H]arginine-to-[3H]citrulline conversion assay. Total NO synthase activity, as measured by this assay, was found to be less in aganglionic than in ganglionic colon. When the total activity was divided into its four known isoforms, aganglionic colon was noted to be striking deficient in the isoform derived primarily from nerves. Conclusion. We conclude that aganglionic colon is deficient in NO synthase-containing nerves. This deficiency could prevent smooth muscle relaxation in the aganglionic colon of patients with Hirschsprung's disease.

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