Adenosine is a putative endogenous sleep-inducing substance, and nitric oxide has been implicated in arousal and sleep mechanisms. We found that various nitric oxide donors, including diethylamine NONOate (DEA/NO), stimulated large increases in extracellular adenosine in nearly pure cultures of forebrain neurons. The effect of DEA/NO could be blocked by 2-phenyl-4,4,5, 5-tetramethyl-imidazoline...

BACKGROUND The effect of ketamine on vasodilation mediated by adenosine triphosphate (ATP)-sensitive K(+) channels has not been studied. The present study was designed to determine whether ketamine might stereoselectively affect vasorelaxation induced by an ATP-sensitive K(+) channel opener in the isolated rat aorta. METHODS Rings of the rat aorta with or without endothelium were suspended fo...

Chimeric molecules are single-chemical entities that possess at least two separate functions. In the design of new chimeric medicines, the two biologic actions are often designed to be synergistic and, thereby, complement each other in activating a specific target, such as a gene, a receptor, or an enzyme. In most chimeric molecules, one functionality is designed to provide a high affinity to a...

Innovative biomaterial strategies are required to improve islet cell retention, viability, and functionality, and thereby obtain clinically successful outcomes from pancreatic islet cell transplantation. To address this need, we have developed a peptide amphiphile-based nanomatrix that incorporates multifunctional bioactive cues and sustained release of nitric oxide. The goal of this study was ...

The role of nitric oxide after poliovirus infection of the human HeLa (carcinoma) and U937 (promonocytic) cell lines has been analyzed. Both types of cells produced detectable levels of nitric oxide after poliovirus infection. However, this production was not sufficient to limit viral productivity. On the other hand, pretreatment with the nitric oxide donor glycerine trinitrate lengthened the c...

INTRODUCTION There are conflicting data on the ability of human mononuclear cells to produce nitric oxide (NO). We investigated nitric oxide production from peripheral blood mononuclear cells (PBMs) by using a new sensitive fluorescent indicator. MATERIALS AND METHODS PBMs from healthy volunteers were collected, plated in 96-well microplates, and loaded with the fluorescent nitric oxide probe...

1. A few studies have shown that nitric oxide may exert cytotoxic and/or steroidogenic effects on cultured ovarian cells but the source of this factor within the ovary remains equivocal. 2. In this study we have investigated the effects of nitric oxide on progesterone secretion, cell viability and cell morphology of cultured rat granulosa/lutein cells and examined whether granulosa cells are an...