Comparison of nitric oxide production by monocyte/macrophages in healthy subjects and patients with active pulmonary tuberculosis

The aim of the present study was to determine the NO production by human cultured macrophages (m phi) and to compare the NO production between healthy subjects and patients with active pulmonary tuberculosis. The bioassay method was used for assessment of validation. Lipopolysaccharide (125 ng ml(-1))-activated m phi from healthy and diseased subjects released a substantial amount of NO. NO synthase inhibitor, N-G-nitro-L-arginine methyl ester, (0.1 mmol l(-1)) suppressed NO synthesis significantly in m phi of healthy subjects. Nitrite formation measured by the diazotization method in the supernatants taken from cultured m phi of tuberculous patients were significantly lower than the healthy subjects. The supernatants obtained in both subjects caused relaxations of guinea-pig aorta reversed by methylene blue (10 mu mol l(-1)). There was a significant difference between relaxations of healthy and diseased supernatants. Nitrite formation measured by the bioassay method in the supernatants taken from cultured m phi of tuberculous patients was significantly higher than the healthy subjects. It was concluded that NO production appeared to be decreased in tuberculosis. The reason for decreased production of NO in tuberculosis may be related to the interaction of several cytokines and/or eicosanoids by means of the disease related induction of immune reactions. (C) 1998 The Italian Pharmacological Society

Studies on the vascular effects of the fractions and phenolic compounds isolated from Viscum album ssp album

Viscum album L. has been used in the indigenous system of medicine for treatment of various diseases such as atherosclerosis and hypertension. In the literature, phenylpropan and flavonoid derivatives were suggested to play a role in the inhibition of cyclic adenosine monophosphate (cAMP)-phosphodiesterase (PDE) and a correlation was proposed between the in vitro inhibition of PDE and in vivo pharmacological activity. The Vascular effects of the phenolic compounds and subfractions isolated from n-butanolic fraction of V. album ssp. album were studied on noradrenaline-contracted rat aortic rings. Isolated phenolic compounds (Syringin (VA-1), Coniferin (VA-9), 5,7-dimethoxy-flavanone-4'-O-[beta-D-apiofuranosyl(1 --> 2)]-beta-D-glucopyranoside (VA-4)) produced concentration-dependent contractions in rat aortic rings. Only one compound (Kalopanaxin D (VA-15)) displayed very slight relaxant response. The weak concentration-dependent relaxing effect of the subfractions gave the idea that vasodilator activity were observed in the less polar subfractions. In addition, there was no clear correlation between the weak relaxant effects of subfractions and an inhibitory effect on cAMP-PDE. (C) 2000 Published by Elsevier Science Ireland Ltd. All rights reserved

Propofol and Intralipid Interact with Reactive Oxygen Species: A Chemiluminescence Study

Scopu

The comparison of the responsiveness of human isolated internal mammary and gastroepiploic arteries to levcromakalim: An alternative approach to the management of graft spasm

Aims We studied the effectiveness of levcromakalim, a potassium channel opener (KCO), in the prevention and reversal of spasm in arterial grafts used in coronary artery bypass operations, namely, internal mammary artery (IMA) and gastroepiploic artery (GEA)

The comparison of vascular reactivities of arterial and venous grafts to vasodilators: Management of graft spasm

Graft spasm in the perioperative or postoperative period increases the risk of morbidity and mortality after coronary revascularization and hence necessitates urgent treatment. We have studied the effects of various vasodilators against noradrenaline- and endothelin-1-induced spasms in saphenous vein, internal mammary artery and gastroepiploic artery. In internal mammary and gastroepiploic arteries, the nitrovasodilators, sodium nitroprusside and glyceryl trinitrate, effectively reversed the spasms induced either with noradrenaline (for sodium nitroprusside; internal mammary artery: 101.07% +/- 1.63%; gastroepiploic artery: 94.10% +/- 2.07%) or endothelin-1 (for sodium nitroprusside; internal mammary artery: 97.67% +/- 4.94%; gastroepiploic artery: 90.69% +/- 2.61%). However, in saphenous vein contracted with endothelin-1, the responsiveness to nitrovasodilators was significantly blunted (for sodium nitroprusside: 52.33% +/- 5.19%) than that of rings contracted with noradrenaline (for sodium nitroprusside: 95.04% +/- 1.94%). Both arterial and venous grafts exhibited moderate beta-receptor function in response to isoproterenol, Isoproterenol was less effective in inhibiting the contractions of endothelin-1 in saphenous vein and gastroepiploic artery but not in internal mammary artery. On the other hand, nifedipine and papaverine were fully effective in reversing all the spasms in three of the graft materials. From these results, it can be deduced that saphenous vein is refractory against cyclic guanidine monophosphate (cGMP)-dependent and beta-receptor mediated relaxations when endothelin-1 was used as the spasmogenic agent. Internal mammary artery is the most responsive graft material to the vasodilators regardless of the nature of spasmogenic stimulus. Gastroepiploic artery exhibits functional similarity with internal mammary artery, with the exception of beta-receptor responsiveness