PMID- 7681897
OWN - NLM
STAT- MEDLINE
DCOM- 19930505
LR  - 20190724
IS  - 0160-2446 (Print)
IS  - 0160-2446 (Linking)
VI  - 21
IP  - 4
DP  - 1993 Apr
TI  - Preliminary evidence for the mechanism underlying the development of tolerance to 
      prazosin in congestive heart failure: the alpha-agonistic properties of 
      dobutamine unmasked by prazosin treatment.
PG  - 537-43
AB  - The hemodynamic effects of acute and chronic treatment with different 
      vasodilators were assessed in patients with chronic heart failure of New York 
      Heart Association (NYHA) class III-IV. Each of 24 patients was randomly 
      allocated; 6 to each of four groups: isosorbide dinitrate, dihydralazine, 
      captopril, or prazosin. In addition, we evaluated the hemodynamic response to 
      dobutamine by using increasing infusion rates of 2.5, 5.0, and 10.0 
      micrograms/kg/min at the start and end of a 3-month period of chronic therapy 
      with either vasodilator. Dobutamine caused a dose-dependent increase in cardiac 
      index and a decrease in mean pulmonary artery pressure (PAP) at the start of the 
      vasodilatory treatment and maintained the effects during a 3-month period of 
      chronic treatment with either isosorbide dinitrate, dihydralazine, or captopril. 
      After 3-month therapy with 6 mg/day prazosin, however, mean PAP was increased 
      above pretreatment value and dobutamine caused a further increase in PAP, thus 
      reversing the initial effects. The dobutamine-induced increase in cardiac index 
      remained virtually unchanged. We conclude that the reversal of the effects on PAP 
      after chronic treatment with prazosin may be, at least in part, due to 
      upregulation of alpha 1-adrenoceptors. This appears to be unmasked by the alpha 
      1-adrenoceptor agonist of the (-)-enantiomer of the racemic mixture of 
      (+/-)-dobutamine.
FAU - Kersting, F
AU  - Kersting F
AD  - Department of Internal Medicine-Cardiology, Hospital Evangelisches Stift St. 
      Martin, Koblenz, Germany.
FAU - Kupp, M
AU  - Kupp M
FAU - Giesen, G
AU  - Giesen G
LA  - eng
PT  - Clinical Trial
PT  - Comparative Study
PT  - Journal Article
PT  - Randomized Controlled Trial
PL  - United States
TA  - J Cardiovasc Pharmacol
JT  - Journal of cardiovascular pharmacology
JID - 7902492
RN  - 0 (Adrenergic alpha-Agonists)
RN  - 0 (Vasodilator Agents)
RN  - 3S12J47372 (Dobutamine)
RN  - XM03YJ541D (Prazosin)
SB  - IM
MH  - Adrenergic alpha-Agonists/administration & dosage
MH  - Adult
MH  - Aged
MH  - Dobutamine/administration & dosage/*therapeutic use
MH  - Dose-Response Relationship, Drug
MH  - Drug Administration Schedule
MH  - Drug Tolerance
MH  - Female
MH  - Heart Failure/*drug therapy
MH  - Hemodynamics/*drug effects
MH  - Humans
MH  - Infusions, Intravenous
MH  - Male
MH  - Middle Aged
MH  - Prazosin/*therapeutic use
MH  - Up-Regulation/drug effects
MH  - Vasodilator Agents/administration & dosage/*therapeutic use
EDAT- 1993/04/01 00:00
MHDA- 1993/04/01 00:01
CRDT- 1993/04/01 00:00
PHST- 1993/04/01 00:00 [pubmed]
PHST- 1993/04/01 00:01 [medline]
PHST- 1993/04/01 00:00 [entrez]
AID - 10.1097/00005344-199304000-00005 [doi]
PST - ppublish
SO  - J Cardiovasc Pharmacol. 1993 Apr;21(4):537-43. doi: 
      10.1097/00005344-199304000-00005.