[Platelet adrenergic alpha receptors in hypertensive subjects undergoing treatment with calcium antagonists].
The effects of two different calcium-channel blocking agents on platelet alpha-2 adrenoceptors were studied in 18 mild to moderate hypertensive patients. The subjects were randomly assigned in a double blind fashion to treatment with either nifedipine 10 mg t.i.d. or tiapamil 300 b.i.d. for six weeks. Platelet alpha-2 receptors were studied before and following 6 weeks of treatment using radioligand binding assay (3H Rauwolscine). Both agents induced a reduction in alpha-2 receptors, which reached statistical significance only for nifedipine. Such a reduction may contribute to the antihypertensive effect of calcium-channel blocking drugs.
Radaelli
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A
Dipartimento di Medicina Interna e Terapia medica, Università di Pavia.
Caporotondi
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A
Muggia
C
C
Pompei
R
R
Marchesi
E
E
D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*
D002121:Calcium Channel Blockers; D011942:Receptors, Adrenergic, alpha
I recettori alfa-adrenergici piastrinici in soggetti ipertesi in trattamento con calcio-antagonisti.