Cross-disciplinarity in the advance of Antarctic ecosystem research.

The biodiversity, ecosystem services and climate variability of the Antarctic continent and the Southern Ocean are major components of the whole Earth system. Antarctic ecosystems are driven more strongly by the physical environment than many other marine and terrestrial ecosystems. As a consequence, to understand ecological functioning, cross-disciplinary studies are especially important in Antarctic research.

Morphine responsiveness in a group of well-defined multiple sclerosis patients: a study with i.v. morphine.

Pain in multiple sclerosis (MS) is more common than has previously been believed. About 28% of all MS patients suffer from central pain (CP), a pain that is difficult to treat. In the present study we have investigated the responsiveness of this pain to morphine.

Tissue disposition of glyceryl trinitrate, 1,2-glyceryl dinitrate, and 1,3-glyceryl dinitrate in tolerant and nontolerant rats.

The tissue distribution of glyceryl trinitrate (GTN) and its two dinitrate metabolites 1,2-glyceryl dinitrate (1,2-GDN) and 1,3-glyceryl trinitrate (1,3-GDN), was studied in GTN-tolerant and nontolerant male Sprague-Dawley rats. The concentrations of GTN, 1,2-GDN, and 1,3-GDN were measured in plasma, heart, brain, liver, aortic tissue, and adipose tissue at various time points after a subcutaneous dose of GTN (50 mg/kg). At the first time point (5 hr), concentrations of GTN, 1,2-GDN, and 1,3-GDN in plasma were equal for tolerant and nontolerant rats, but the elimination rate was altered for the tolerant rats as compared with nontolerant rats.

Tissue levels of glyceryl trinitrate and cGMP after in vivo administration in rat, and the effect of tolerance development.

The present study compares the tissue distribution of glyceryl trinitrate (GTN) in plasma, heart, brain, aortic tissue, and adipose tissue from GTN tolerant and GTN nontolerant rats at various time points. Furthermore, the cGMP levels in brain, heart, and aortic tissue were studied at various time points as well as the concentration-effect relationship for GTN in aorta isolated at different time points after the last exposure to GTN. Concentrations of GTN were found to be higher in all tissues studied as compared with plasma, and the concentrations of GTN were higher in tissues from tolerant rats as compared with nontolerant rats, except for aortic tissue.

Tissue distribution of glyceryl trinitrate and the effect on cGMP levels in rat.

In order to study distribution in tissue, rats were treated subcutaneously with glyceryl trinitrate, GTN, (50 mg/kg). The concentrations of GTN were measured in plasma, brain, heart, adipose tissue and aortic tissue at different sampling times by a gas chromatographic method with electron-capture detection. The peak GTN-concentration was reached after 2 hours in all tissues examined.