PMID- 1977324
OWN - NLM
STAT- MEDLINE
DCOM- 19901119
LR  - 20171213
IS  - 0002-9513 (Print)
IS  - 0002-9513 (Linking)
VI  - 259
IP  - 4 Pt 2
DP  - 1990 Oct
TI  - Reduced beta-agonist sensitivity in single atrial cells from failing human 
      hearts.
PG  - H1009-14
AB  - Human myocytes were isolated from right atrial appendage, and contractile 
      responses to inotropic agents were studied. Responses to inotropic agents of 
      cells isolated from patients with mild heart disease [New York Heart Association 
      (NYHA) classes I and II] were compared with those of myocytes from rabbit atria. 
      Maximally effective concentrations of calcium, forskolin, and isoproterenol 
      increased contraction amplitude to a similar extent (11.9, 11.5, and 11.3% change 
      in cell length, respectively), but histamine produced a smaller effect (7.1%). 
      The maximum responses of rabbit atrial cells to calcium (18.5%) and isoproterenol 
      (15.0%) were significantly greater than human. In human cells, the velocity of 
      contraction or relaxation was accelerated more by isoproterenol (P less than 
      0.05) or forskolin (P less than 0.01) than by high calcium. Only relaxation 
      velocity was increased by isoproterenol in rabbit cells (P less than 0.05). 
      Rabbit myocytes contracted and relaxed 10-30% faster than human (P less than 
      0.05). Cells from the atria of patients with New York Heart Association (NYHA) 
      heart failure class III or IV were less responsive to isoproterenol than those 
      from class I or II (P less than 0.01). Omitting data from patients who had been 
      taking calcium-channel blockers or beta-adrenoceptor agonist or antagonist drugs 
      did not affect the conclusions. Analysis of variance revealed a significantly 
      greater between-patient than within-patient variation (P less than 0.001), 
      indicating that cells from the same patient have a tendency to respond in a 
      similar way. Responses to high calcium did not differ among NYHA classes. The 
      effect of forskolin was not reduced in NYHA class III, although there was a 
      decreased response in cells from two patients in NYHA class IV.(ABSTRACT 
      TRUNCATED AT 250 WORDS)
FAU - Harding, S E
AU  - Harding SE
AD  - Department of Cardiac Medicine, National Heart and Lung Institute, London, United 
      Kingdom.
FAU - Jones, S M
AU  - Jones SM
FAU - O'Gara, P
AU  - O'Gara P
FAU - Vescovo, G
AU  - Vescovo G
FAU - Poole-Wilson, P A
AU  - Poole-Wilson PA
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Am J Physiol
JT  - The American journal of physiology
JID - 0370511
RN  - 0 (Adrenergic beta-Agonists)
RN  - 0 (Cardiotonic Agents)
RN  - 0 (Diuretics)
RN  - L628TT009W (Isoproterenol)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Adrenergic beta-Agonists/*pharmacology
MH  - Animals
MH  - Calcium/pharmacology
MH  - Cardiac Output, Low/drug therapy/*physiopathology
MH  - Cardiotonic Agents/pharmacology
MH  - Cell Separation
MH  - Diuretics/therapeutic use
MH  - Heart/*drug effects/physiopathology
MH  - Heart Atria
MH  - Humans
MH  - Isoproterenol/pharmacology
MH  - Myocardial Contraction
MH  - Myocardium/cytology
MH  - Reference Values
MH  - Stroke Volume
EDAT- 1990/10/01 00:00
MHDA- 1990/10/01 00:01
CRDT- 1990/10/01 00:00
PHST- 1990/10/01 00:00 [pubmed]
PHST- 1990/10/01 00:01 [medline]
PHST- 1990/10/01 00:00 [entrez]
AID - 10.1152/ajpheart.1990.259.4.H1009 [doi]
PST - ppublish
SO  - Am J Physiol. 1990 Oct;259(4 Pt 2):H1009-14. doi: 
      10.1152/ajpheart.1990.259.4.H1009.