Increase of myocardial inhibitory G-proteins in catecholamine-refractory septic shock or in septic multiorgan failure.
OBJECTIVE
The aim of the study was to investigate the mechanisms of myocardial catecholamine refractoriness in septic shock.


METHODS
The inhibitory guanine nucleotide-binding proteins (Gi alpha) were studied with pertussis toxin labeling and radioimmunologically in myocardium from patients who died while in catecholamine-refractory septic shock and from patients who died of noncardiac disease.


RESULTS
An increase by 62% (immunological Gi alpha) and 221% (pertussis toxin substrate) of myocardial Gi alpha was observed in patients with catecholamine-refractory shock compared with controls. The increases of Gi alpha were greater than those found in chronic heart failure reported earlier.


CONCLUSIONS
An increase in the expression of Gi alpha could also be important in conditions other than chronic heart failure, eg, septic shock. An increase of Gi alpha could play a pathophysiologically relevant role in catecholamine refractoriness in septic shock and could provide a target for pharmacologic treatment in this condition.
Department of Internal Medicine III, University of Cologne, Germany.
M
M
Böhm
R
R
Kirchmayr
P
P
Gierschik
E
E
Erdmann
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D001345:Autoradiography; D002395:Catecholamines / Q000627:therapeutic use*; D004351:Drug Resistance; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D009102:Multiple Organ Failure / Q000188:drug therapy / Q000378:metabolism* / Q000382:microbiology; D009206:Myocardium / Q000378:metabolism*; D037342:Pertussis Toxin; D011863:Radioimmunoassay; D012772:Shock, Septic / Q000188:drug therapy / Q000378:metabolism* / Q000382:microbiology; D010566:Virulence Factors, Bordetella
D002395:Catecholamines; D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins