Disease relevance of m-Hydroxynorephedrine

• Metaraminol for priapism [1].
• Five other baboons (Group B) were subjected to hypertension (121 +/- 2 mmHg) induced by metaraminol and were compared with their base line state (81 +/- 10 mmHg) [2].
• Effect of metaraminol during acute inferior wall myocardial infarction accompanied by hypotension: preliminary study [3].
• These results indicate that in a selected group of patients with acute inferior myocardial infarction, metaraminol administration (in certain hemodynamic circumstances) can alleviate acute ischemia within a few minutes and thereby reduce ischemic injury [3].
• Mollaret's meningitis. A variant of recurrent hereditary polyserositis, both provoked by metaraminol [4].

High impact information on m-Hydroxynorephedrine

• Metaraminol for haemodialysis-associated priapism [5].
• Metaraminol provocation test for familial Mediterranean fever [6].
• The average heart rate decreased from 82 +/- 11 to 69 +/- 9 beats/min (p less than 0.05) and the mean arterial blood pressure increased from 81 +/- 12 mm Hg before metaraminol treatment to 126 +/- 8 mm Hg after treatment [3].
• Interrelationship between the breakdown of the blood-brain barrier (BBB) to Evans blue and elevations in the regional cerebral blood flow (rCBF) was studied in rabbits subjected to adrenaline- or metaraminol-induced systemic hypertension and also in bicuculline-induced seizures [7].
• Autoregulation was tested by exsanguination and metaraminol infusion with the monkeys inspiring from air, 9% and 12% carbon dioxide in air [8].

Chemical compound and disease context of m-Hydroxynorephedrine

• At week 52, administration of metaraminol and phenylephrine at the higher dose significantly increased the incidence of gastric cancers, the ornithine decarboxylase activity of the gastric cancers and the labeling index of the antral epithelial cells [9].
• CONCLUSIONS: When used by infusion to maintain arterial pressure during spinal anesthesia for cesarean section, metaraminol was associated with less neonatal acidosis and more closely controlled titration of arterial pressure compared with ephedrine [10].
• Norepinephrine and metaraminol in septic shock: a comparison of the hemodynamic effects [11].
• We present two cases of anaphylaxis under anaesthesia where return of spontaneous circulation was refractory to epinephrine, but occurred following the administration of the alpha-agonist metaraminol [12].
• Hypotension occurred two minutes after injection of bupivacaine in three of the eleven shocked patients, but was corrected with fluids and metaraminol without difficulty [13].

Biological context of m-Hydroxynorephedrine

• MEASUREMENTS and RESULTS--Following AV block due to ablation, a heart rate increase (or no change) was found in 87.5% of 56 arterial pressure increases produced by elevation of an open arterial blood reservoir or by metaraminol infusion, but in only 21.8% of 55 pressure decreases caused by arterial bleeding (p much less than 0.001) [14].
• Here, we measured changes in TBF in rat solid tumour LY80 during continuous administration of AVE8062-like epinephrine or four catecholamines that are unlike AVE8062 (norepinephrine, dopamine, methoxamine, and metaraminol) to the region of increased vascular resistance [15].
• The administration of albumin and metaraminol bitartate prevents hypotension due to fluid shifts or compartmental venous dilatation [16].
• Neither at 100 mmol/l Na+ nor at 50 mmol/l Na+ was there any consistent, concentration-dependent effect of K+ on the IC50 values of desipramine, cocaine and (-)metaraminol [17].
• Replacement norepinephrine with metaraminol did not modify hemodynamic variables; in particular there were no changes in heart rate, stroke volume index, pulmonary artery occlusion pressure, or oxygen consumption index [11].

Anatomical context of m-Hydroxynorephedrine

• 3. Increases in arterial pressure sufficient to activate peripheral baroreceptors were achieved by intravenous bolus infusions of metaraminol (10 micrograms/10 microliters) [18].
• Conversely, metaraminol permeated the membrane of the chromaffin granule through the apolar lipid phase and distributed according to the delta pH alone [19].
• In the gerbil, 4 hours after placing a clip on one carotid artery, metaraminol-induced increases in blood pressure had no such protective effect on the metabolic changes or on oedema [20].
• To examine whether the uterine perfusion-sparing property of ephedrine is due to local actions, we examined the effects in vitro of ephedrine and the alpha-adrenergic agonist metaraminol (10(-10)-10(-3) M) in uterine and femoral vessels, with and without functional endothelium, from nonpregnant and pregnant ewes [21].
• The disappearance of LAQ094, metaraminol, and (-)-isoproterenol following 1-h incubation with human liver microsomes was 73, 85, and 66%, respectively, in the presence of 1% methanol, but was only 3, 15, and 24%, respectively, in the absence of organic solvent [22].

Associations of m-Hydroxynorephedrine with other chemical compounds

• Autoregulation was tested with metaraminol or angiotensin infusion and the autoregulation index (A.I.) was calculated [23].
• This myocardial ischaemia was refractory to nitroglycerin and, in every patient, the increases in blood pressure induced by metaraminol (to a mean systolic blood pressure of 191 +/- 22 mmHg) preceded reversal of the ECG changes [24].
• No patient in the metaraminol group had umbilical arterial pH less than 7.2, compared with nine patients (39%) in the ephedrine group (P = 0.0005) [10].
• Guinea-pig liver concentrated metaraminol to a greater extent than did rat liver; the concentration of metaraminol was lowered by desipramine pretreatment and, within three tissues of the guinea pig (heart greater than liver greater than muscle), paralleled the concentration of endogenous norepinephrine [25].
• Repeated intravenous injections of the alpha-adrenoceptor agonist, metaraminol, similarly evoked approximately 50 mmHg increments in blood pressure and a 26% increase in GABA outflow (P < 0.05) [26].

Gene context of m-Hydroxynorephedrine

• Meningismus after metaraminol administration in a patient with Familial Mediterranean fever [27].
• 5. The presynaptic alpha 2-adrenoreceptor antagonists idazoxan and yohimbine, and the neuronal uptake blockers desipramine and metaraminol, prolonged the PTP and enhanced but shortened the secondary rise in tetanic tension [28].
• In 15 other cases with a SBP 134.9 +/- 18.3 mmHg and no PVC's at rest a metaraminol infusion was started [29].

Analytical, diagnostic and therapeutic context of m-Hydroxynorephedrine

• Metaraminol provocative test: a specific diagnostic test for familial Mediterranean fever [30].
• In a placebo-controlled, double-blind, cross-over study a challenge with a 10 mg dose of metaraminol infusion was followed within 48 h by a typical disease-like attack in all of 21 patients with familial Mediterranean fever but in none of 21 control subjects [30].
• CBF was measured during steady state levels of hypo- and hypertension induced by phlebotomy, or by intravenous metaraminol, over the MABP range of 48-205 mm Hg [31].
• Infusions of metaraminol and angiotensin were used to test the effect of increased perfusion pressure on tissue metabolism and oedema after induction of regional cerebral ischaemia in the rat and the gerbil [20].
• These data suggest that both ephedrine and metaraminol constrict uterine and systemic vessels by actions on alpha adrenoceptors, and that ephedrine may spare uterine perfusion during pregnancy due to more selective constriction of systemic vessels than that caused by metaraminol [21].

References