In the present study we aimed to assess the effect of alpha(1)-adrenoceptor blockade on resting and hyperemic myocardial blood flow in normal humans. Myocardial blood flow, at baseline and after dipyridamole, was measured with positron emission tomography and O-15-labeled water in 11 normal volunteers at control and during alpha(1)-blockade with doxazosin. Baseline myocardial blood flow during alpha(1)-blockade was not different from control, whereas coronary resistance was significantly lower (73.48 +/- 18.31 vs. 89.84 +/- 27.96 mmHg . min . ml(-1). g(-1); P < 0.05). After dipyridamole, myocardial blood flow during alpha(1)-blockade was significantly higher (3.50 +/- 0.75 vs. 2.58 +/- 0.54 ml . min(-1). g(-1); P < 0.01) and coronary resistance lower (25.30 +/- 7.37 vs. 33.89 +/- 7.04 mmHg . min . ml(-1). g(-1); P < 0.01) compared with control. In conclusion, in normal humans, dipylidamole-induced increase in myocardial blood flow is limited by alpha(1)-mediated coronary vasoconstriction.

Effect of alpha(1)-adrenoceptor blockade on resting and hyperemic myocardial blood flow in normal humans

CAMICI , PAOLO
1996

Abstract

In the present study we aimed to assess the effect of alpha(1)-adrenoceptor blockade on resting and hyperemic myocardial blood flow in normal humans. Myocardial blood flow, at baseline and after dipyridamole, was measured with positron emission tomography and O-15-labeled water in 11 normal volunteers at control and during alpha(1)-blockade with doxazosin. Baseline myocardial blood flow during alpha(1)-blockade was not different from control, whereas coronary resistance was significantly lower (73.48 +/- 18.31 vs. 89.84 +/- 27.96 mmHg . min . ml(-1). g(-1); P < 0.05). After dipyridamole, myocardial blood flow during alpha(1)-blockade was significantly higher (3.50 +/- 0.75 vs. 2.58 +/- 0.54 ml . min(-1). g(-1); P < 0.01) and coronary resistance lower (25.30 +/- 7.37 vs. 33.89 +/- 7.04 mmHg . min . ml(-1). g(-1); P < 0.01) compared with control. In conclusion, in normal humans, dipylidamole-induced increase in myocardial blood flow is limited by alpha(1)-mediated coronary vasoconstriction.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11768/2857
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 36
social impact