Nitric oxide is an important cellular mediator that plays a role in regulating cellular proliferation of both normal and tumor cells. In the present study, we characterized nitric oxide production by the human colon adenocarcinoma cell line DLD-1 and examined the effects of 5-fluorouracil (5-FUra), an antimetabolite effective against colon tumors, on nitric oxide production. IFN-y was found to ...

Nitric oxide is produced by almost all cardiac cells, endothelial cells, cardiomyocytes and nerve fibers. It is synthesized by an enzyme, a nitric oxide synthase, which occurs in endothelial, neural and inducible form. The distribution of nitric oxide synthase in the heart is characterized by a pronounced non-uniformity. Nitric oxide exerts its effects in physiological and pathophysiological co...

Nitric oxide is an important cellular mediator that plays a role in regulating cellular proliferation of both normal and tumor cells. In the present study, we characterized nitric oxide production by the human colon adenocarcinoma cell line DLD-1 and examined the effects of 5-fluorouracil (5-FUra), an antimetabolite effective against colon tumors, on nitric oxide production. IFN-gamma was found...

PURPOSE To investigate the cellular origin of nitric oxide released from the rabbit retina in response to physiological stimulation with light. METHODS The release of nitric oxide from the retina was measured in rabbits anesthetized with urethane. An eye-cup was prepared and was filled with Krebs-Ringer bicarbonate. After washing for 45 minutes, 0.5 ml medium was placed in the eyecup. The med...

The development of multidrug resistance (MDR) not only actively transports a wide range of cytotoxic drugs across drug transporters but is also a complex interaction between a number of important cellular signalling pathways. Nitric oxide donors appear to be a new class of anticancer therapeutics for satisfying all the above conditions. Previously, we reported furoxan-based nitric oxide-releasi...

Nitric oxide (NO) is involved in several biological processes, but its role in human melanogenesis is still not well understood. Exposure to UVA and UVB induces nitric oxide production in keratinocytes and melanocytes through the activation of constitutive nitric oxide synthase, increasing tyrosinase activity and melanin synthesis, whereas inducible nitric oxide synthase over expression might b...

Nitric oxide plays a central role in the physiology and pathology of diverse tissues including the immune system. It is clear that the levels of nitric oxide must be carefully regulated to maintain homeostasis. Appropriate levels of nitric oxide derived from iNOS assist in mounting an effective defense against invading microbes. Conversely, inability to generate nitric oxide results in serious,...

BACKGROUND Inhaled nitric oxide produces potent pulmonary vasodilation by activating soluble guanylate cyclase and increasing smooth muscle cell concentrations of cyclic guanosine monophosphate. However, responses are often nonsustained, and clinically significant increases in pulmonary vascular resistance have been noted on its acute withdrawal. In vitro and in vivo data suggest that inhaled n...

Inhaled nitric oxide is a selective pulmonary vasodilator used for the treatment of pulmonary hypertension. The potential adverse effects of inhaled nitric oxide are unknown and represent the focus of the present studies. Whereas inhalation of nitric oxide (10 to 100 ppm, 5 h) by Balb/c mice had no effect on the number or type of cells recovered from the lung, a dose-related increase in broncho...

Purification of soluble guanylate cyclase from rat liver resulted in an apparent loss of enzyme activation by nitric oxide that could be restored by dithiothreitol. methemoglobin, bovine serum albumin, or sucrose. Although hemoglobin also permitted some activation with nitric oxide, the effect of other agents to restore enzyme activation was prevented with hemoglobin. As a result of enzyme puri...