Effects of dopamine, dopexamine and dobutamine on renal excretory function during experimental sepsis in conscious rats.
BACKGROUND
Acute renal failure is a frequent complication in human sepsis. Various inotropic drugs are often used to improve central haemodynamics and renal function. The differential preservative role of the most commonly used inotropic drugs on renal function, in this condition, has previously not been extensively studied. The aim of this experimental animal study was therefore to compare the preserving effects of dopamine, dopexamine, dobutamine and saline on renal excretory function, after induction of sepsis in conscious rats.


METHODS
The effects of dopamine (DA) (2.5 micrograms.kg-1.min-1; n = 11), dopexamine (DX) (1 microgram.kg-1.min-1; n = 10), dobutamine (DB) (5 micrograms.kg-1.min-1; n = 10) and saline (n = 13) on the glomerular filtration rate (GFR), urine flow (UF), sodium excretion (SE) and fractional urinary excretion of sodium (FUENa) were studied and compared in conscious rats subjected to a 1-h infusion of live E. coli bacteria (10(9)/h).


RESULTS
In the saline-treated control group, bacteria infusion decreased GFR, UF, SE and FUENa by 31%, 53%, 51% and 36% respectively, associated with a 16% decrease in mean arterial pressure (MAP), and a 10% increase in heart rate (HR). In the post-E. coli treatment period, the fall in MAP was less pronounced with DX compared to both DB and control, while there was no difference between DX and DA. The increase in HR was most pronounced with DB. GFR decreased to a lesser extent with DX compared to DA, DB and control. UF and SE were better maintained with DX compared to DB and control, while there was no difference in FUENa between the groups.


CONCLUSIONS
We conclude that dopexamine, to a greater extent than dopamine and dobutamine, improves renal excretory function in experimental septic shock.
Pålsson
J
J
Department of Anaesthesia and Intensive Care, Sahlgrenska University Hospital, Göteborg, Sweden.
Ricksten
S E
SE
Houltz
E
E
Lundin
S
S
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology*; D004280:Dobutamine / Q000494:pharmacology*; D004298:Dopamine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D004927:Escherichia coli Infections / Q000503:physiopathology; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007668:Kidney / Q000187:drug effects / Q000503:physiopathology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D018805:Sepsis / Q000503:physiopathology*; D012772:Shock, Septic / Q000503:physiopathology; D012964:Sodium / Q000652:urine; D014556:Urine; D014665:Vasodilator Agents / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D002316:Cardiotonic Agents; D014665:Vasodilator Agents; C046318:dopexamine; D004280:Dobutamine; D012964:Sodium; D004298:Dopamine