These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Clonidine lowers blood pressure independently of renin suppression in patients with unilateral renal artery stenosis.
    Author: Mathias CJ, Wilkinson A, Lewis PS, Peart WS, Sever PS, Snell ME.
    Journal: Chest; 1983 Feb; 83(2 Suppl):357-9. PubMed ID: 6337026.
    Abstract:
    The effects of 300 micrograms of oral clonidine were studied in nine patients with unilateral renal artery stenosis proved by selective renal arteriography. Blood pressure, heart rate, plasma renin activity (PRA) levels, plasma noradrenaline levels, and sedation were measured before and for eight hours after dosage. After clonidine administration, both systolic and diastolic blood pressure fell within the first hour, was maximum in the fourth hour, and remained lower than predosage levels even in the eighth hour. There was a fall in heart rate, maximum in the fourth hour. There were minimal changes in PRA levels after giving the clonidine. Plasma noradrenaline levels fell, with the maximum fall in the sixth hour. Sedation occurred within one hour of dosage and was maximum in the second hour. We conclude that in patients with unilateral renal artery stenosis clonidine causes a substantial and prolonged fall in blood pressure not accompanied by suppression of PRA levels but by a reduction in plasma noradrenaline levels. This suggests a role for central pressor mechanisms, probably linked to angiotensin II and central sympathetic activation, in the maintenance of hypertension in patients with renal artery stenosis.
    [Abstract] [Full Text] [Related] [New Search]