Cardiovascular Effects Of Nitroglycerin Research Articles

Comparative analysis of the neuronal activation and cardiovascular effects of nitroglycerin, sodium nitroprusside and l-arginine

In this study, we compare the biological effects, Fos expression and cardiovascular responses induced in the rat, of different nitric oxide modulators (nitroglycerin, sodium nitroprusside and l-arginine). Nitroglycerin and sodium nitroprusside induced a similar pattern of neuronal activation in several areas, which include the paraventricular and supraoptic nuclei of the hypothalamus, central nucleus of the amygdala, parabrachial nucleus, locus coeruleus, ventrolateral medulla and nucleus tractus solitarius. However, only nitroglycerin activated the periaqueductal grey and nucleus trigeminalis caudalis. l-Arginine-induced neuronal activation was restricted to the paraventricular and supraoptic nuclei of the hypothalamus. As regards cardiovascular effect, both nitroglycerin and sodium nitroprusside induced moderate hypotension (nitroglycerin: −23.3%, sodium nitroprusside: −24.3%) that lasted 40 min in the case of sodium nitroprusside and 80 min in the case of nitroglycerin. l-Arginine did not significantly influence blood pressure. These data suggest that nitroglycerin, sodium nitroprusside and l-arginine are associated with different biological effects on both the central nervous system and the cardiovascular system. Of the NO-related drugs tested in this study, only nitroglycerin confirmed its ability to activate brainstem areas implicated in nociception.

Central Noradrenergic Activity and the Cardiovascular Effects of Nitroglycerin and Amyl Nitrate

Central Noradrenergic Activity and the Cardiovascular Effects of Nitroglycerin and Amyl Nitrate

Central Noradrenergic Activity and the Cardiovascular Effects of Nitroglycerin and Amyl Nitrate

Intracerebroventricular and i.v. administration of nitroglycerin in anesthetized Sprague-Dawley rats produced dose-dependent decreases in mean arterial pressure and increases in heart rate, but intracisternal injection of the drug induced hypotension and bradycardia. Hypotensive responses to intracisternal injection of nitroglycerin showed that the compound was two to three times more potent than by i.v. administration (six times when comparing the area under the curve). Intravenous sodium nitroprusside produced dose-dependent hypotensive and tachycardiac effects, but minimal responses were induced by i.c.v. and intracisternal injection. Central pretreatment with either yohimbine or rauwolscine antagonized hypotensive responses to i.c.v. and i.v. nitroglycerin, but did not alter the depressor responses induced by i.v. sodium nitroprusside. Tachycardiac responses to i.c.v. nitroglycerin are greater than the responses induced by i.v. administration. Inhalation of amyl nitrite produced marked hypotensive responses, with the dose-response curves being shifted to the right by i.c.v. pretreatment with rauwolscine, but not by i.v. pretreatment. The concentrations of 3,4-dihydroxyphenylglycol and 3-methoxy-4-hydroxyphenylglycol in cerebrospinal fluid were increased by i.v., i.c.v., and intracisternal administration of nitroglycerin, but were not altered by i.v. sodium nitroprusside. The concentrations of dihydroxyphenylacetic acid were elevated by i.v. and i.c.v. injection of nitroglycerin. Results suggest that nitroglycerin stimulates central noradrenergic activity, which may be involved in the component of hypotensive effects of the drug. Reflex tachycardiac responses to nitroglycerin may be further complicated by forebrain stimulation and medulla-mediated bradycardia. Sodium nitroprusside did not demonstrate central activity.

Central Noradrenergic Activity and the Cardiovascular Effects of Nitroglycerin and Amyl Nitrate

Central Noradrenergic Activity and the Cardiovascular Effects of Nitroglycerin and Amyl Nitrate

Cardiovascular effects of nitroglycerin given sublingually and intravenously in unanesthetized and unrestrained dogs

Cardiovascular effects of nitroglycerin given sublingually and intravenously in unanesthetized and unrestrained dogs

Role of Intravenous Nitroglycerin in the Treatment of Severe Pregnancy-Induced Hypertension Complicated by Pulmonary Edema

Intravenous nitroglycerin would appear to be an ideal agent for the treatment of severe pregnancy-induced hypertension complicated by cardiogenic pulmonary edema. Nitroglycerin infusion effectively reduces preload by venous dilatation and, at higher doses, results in arterial vasodilatation. Because of these pharmacologic properties, the effects of intravenous nitroglycerin were studied in three patients with severe pregnancy-induced hypertension complicated by pulmonary edema. The major cardiovascular effects of nitroglycerin were to reduce the mean pulmonary capillary wedge pressure from 27 +/- 4 to 14 +/- 6 mm Hg, which result in a change in the colloid osmotic pressure to pulmonary capillary wedge pressure gradient from -10 to 2 mm Hg. No significant changes occurred in heart rate, central venous pressure, or cardiac index. Analysis of oxygen-related parameters revealed a significant (p less than 0.05) increase in oxygen delivery and extraction accompanied by a 53% increase in oxygen consumption. The changes in oxygen-related variables appeared to be secondary to a fall in mixed venous oxygen tension from 39 +/- 4 to 33 +/- 1 torr. These changes occurred without any significant improvement in arterial oxygen tension. We conclude that while intravenous nitroglycerin expeditiously corrects the hydrostatic derangements of pulmonary edema seen in pregnancy-induced hypertension, a rapid improvement in arterial oxygenation does not occur.

Cardiovascular Effects of Nitroglycerin as a Hypotensive Agent in Cerebral Anaeurysm Surgery

Cardiovascular Effects of Nitroglycerin as a Hypotensive Agent in Cerebral Anaeurysm Surgery

Cardiovascular effects of nitroglycerin as a hypotensive agent in cerebral aneurysm surgery.

The cardiovascular effects of nitroglycerin (TNG) were studied in 20 patients undergoing cerebral aneurysm clipping under controlled hypotension. Total oxygen consumption was also calculated in 15 patients. Mean arterial blood pressure was reduced by 36% from 91 to 58 mmHg (12.1 to 7.7 kPa) by TNG due to decrease in both total peripheral resistance (16%) and cardiac output (24%). Right atrial and pulmonary capillary wedge pressures were reduced during hypotension, indicating a decrease in venous return to the heart. There were no significant changes in total oxygen consumption. It is concluded that the fall in cardiac output results from a reduction in central blood volume due to venous pooling of blood, and that TNG has no major overall metabolic effects.

Animal pharmacology of nitroglycerin

Nitroglycerin, first introduced over a hundred years ago, is now finding wider clinical applications. To a large degree, the renewed interest in the clinical pharmacologic usage of nitroglycerin is due to the availability of new formulations and drug delivery systems. The current review focuses on the physiological and pharmacological actions of nitroglycerin in mammals. Routes of nitroglycerin metabolism, biochemistry and absorption are discussed. The phenomenon of nitroglycerin tolerance is illustrated and related to specific quantitative alterations occurring at the cellular level. The cardiovascular effects of nitroglycerin are discussed in terms of its effects on coronary flow, the myocardium itself, and on the peripheral vasculature. The early speculation of Murrell (3) that nitroglycerin “would probably prove of service in the treatment of angina pectoris…and other vascular disorders…” has now been realized.

Plasma Levels and Cardiovascular Effects of Nitroglycerin in Pregnant Sheep

Plasma Levels and Cardiovascular Effects of Nitroglycerin in Pregnant Sheep

Plasma levels and cardiovascular effect of nitroglycerin in pregnant sheep.

The cardiovascular effects and blood levels of intravenous nitroglycerin in mother and foetus were studied in normotensive and hypertensive ewes. Although nitroglycerin produced a reduction in uterine blood flow following a decrease in blood pressure, there was little if any incidence of adverse effects in the foetus. Nitroglycerin was detected in all but two samples of foetal arterial blood but the foetal/maternal artery ratio was only 0.04. Nitroglycerin merits further evaluation for the treatment of acute hypertensive episodes in the preeclamptic patient.

Attenuation of the cardiovascular effects of nitroglycerin by indomethacin

Attenuation of the cardiovascular effects of nitroglycerin by indomethacin

Dynamics of uterine circulation in pregnant and nonpregnant sheep.

Dynamics of uterine circulation in pregnant and nonpregnant sheep.