Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To improve the diagnosis and management of pheochromocytoma, the results from a comparative study of 34 patients with pheochromocytoma, 33 patients with essential hypertension and 36 normal volunteers are presented. Our data suggest that clinical characteristics indicate the possibility of pheochromocytoma only, while the definite diagnosis of pheochromocytoma must be based on comprehensive analysis of all data obtained from both clinical and laboratory studies. The plasma concentration of free norepinephrine in peripheral veins is helpful in establishing the presence or absence of pheochromocytoma. Both CT scan and meta-I-131-iodobenzylguanidine images are useful noninvasive techniques for localization of pheochromocytoma. Phenoxybenzamine is of benefit in both diagnosis and management of patients with pheochromocytoma.
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PMID:Preoperative diagnosis and management of pheochromocytoma. 271 Jul 92

To determine whether the alpha-adrenergic antagonist phenoxybenzamine would alter cardiovascular or plasma catecholamine response to the alpha-adrenergic agonist clonidine, six patients with pheochromocytomas and eight with labile hypertension were studied. Clonidine, 0.3 mg, was given with and without 48 hr pretreatment with 30 mg/day phenoxybenzamine. The response to 10 mg diazepam was also observed in seven of the subjects who had labile hypertension. In the hypertensive patients, clonidine alone induced a fall in supine blood pressure from 137 +/- 21/91 +/- 14 to 109 +/- 18/76 +/- 17 mm Hg and, with phenoxybenzamine, clonidine reduced blood pressure from 141 +/- 22/89 +/- 10 to 107 +/- 21/72 +/- 11 mm Hg. Plasma norepinephrine fell from 179 +/- 60 to 107 +/- 79 pg/ml without phenoxybenzamine and from 229 +/- 159 to 95 +/- 46 pg/ml with phenoxybenzamine in hypertensive subjects. Responses with phenoxybenzamine did not differ from those without phenoxybenzamine and diazepam induced no cardiovascular or plasma catecholamine changes. Clonidine did not lower plasma catecholamines in patients with a pheochromocytoma in the presence or in the absence of phenoxybenzamine. Blood pressure tended to decline after clonidine in pheochromocytoma patients not taking phenoxybenzamine, but it was not reduced by clonidine when these patients were taking phenoxybenzamine. Phenoxybenzamine does not inhibit reduction in blood pressure and plasma catecholamines induced by clonidine in patients with essential hypertension or interfere with the clonidine suppression test in patients with pheochromocytomas.
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PMID:Effect of phenoxybenzamine on cardiovascular and plasma catecholamine responses to clonidine. 682 28