AIMS To compare the responses between clomipramine, a centrally acting substance, and nitroglycerin, with mainly peripheral action, when each drug is used during tilt test for the induction of vasovagal syncope (VVS). METHODS AND RESULTS Hundred patients with recurrent episodes of classical VVS underwent two tilt tests in a randomized sequence. One test included 20 min of tilt at 60 degrees w...

BACKGROUND Nitrates are widely used to treat coronary artery disease, but their therapeutic value is compromised by the rapid development of tolerance. Recently, the renin-angiotensin system has been suggested to play an important role in the development of nitrate tolerance. METHODS AND RESULTS Sixty-four patients with coronary spastic angina were investigated to clarify the effect of angiot...

The effect of sodium nitrite, amyl nitrite and nitroglycerin (glyceryl trinitrate) on the hemoglobin of adult erythrocytes was examined in vitro. Both amyl nitrite and nitroglycerin reacted immediately with oxyhemoglobin to effect oxidation into methemoglobin while sodium nitrite required an inductionary period (lag phase) prior to the reaction. Kinetic studies of the biomolecular rate law for ...

BACKGROUND Tolerance to the effects of organic nitrates develops rapidly during continuous exposure to these drugs; its main mechanism seems to be an intracellular sulfhydryl group depletion. However, the relative susceptibility to the development of nitroglycerin tolerance of the arterial or venous circulation in humans is still a matter of dispute. METHODS AND RESULTS Twenty patients with c...

Until recently, the use of nitroglycerin in patients with acute myocardial infarction has been contraindicated primarily because of possible hypotension or tachycardia which, with sublingual or oral preparations, would be difficult to control. The introduction of intravenous nitroglycerin and its use during experimentally induced infarction paved the way for its use in patients with acute myoca...

A 62-year-old woman developed pruritus, oedema, erythema and vesiculation, well demarcated at the application sites of nitroglycerin TTS on the trunk and upper arms (Fig. 1). Lesions healed with post-inflammatory hyperpigmentation. Two weeks before, the patient had started treatment for coronary insufficiency with daily nitroglycerin transdermal patches (Dermatrans 5®, Recordati group, Madrid, ...

Within a half-year period, we encountered six cases of patients harmed by the adverse effects of self-administered nitroglycerin--syncope, delayed definitive medical care, and the worsening of nonischemic symptoms. We therefore surveyed 112 patients after a remote myocardial infarction, and 121 cardiologists and internists, regarding the use of sublingual nitroglycerin. Of the physicians, 84 pe...

Background. Tolerance to the effects of organic nitrates develops rapidly during continuous exposure to these drugs; its main mechanism seems to be an intracellular sulfhydryl group depletion. However, the relative susceptibility to the development of nitroglycerin tolerance of the arterial or venous circulation in humans is still a matter of dispute. Methods and Results. Twenty patients with c...

To better understand the mechanism of nitrate tolerance in patients with congestive heart failure, 13 patients received a 24 h infusion of nitroglycerin (1.5 micrograms/kg body weight per min) with or without N-acetylcysteine (225 mg/kg per 24 h). The infusions were separated by a 24 h nitrate-free interval. By the end of the nitroglycerin infusion, mean arterial pressure had returned to baseli...