The effects of beta blockade on dopamine and dobutamine induced hypokalaemia in dogs.
The effect of beta 1 and beta 2 blockade on dopamine and dobutamine induced hypokalaemia was investigated in dogs. Arterial plasma potassium was continuously monitored using a potassium-sensitive electrode sited in the abdominal aorta. Dopamine and dobutamine were infused at 15 micrograms kg-1 min-1 into animals pre-treated with atenolol (0.5 mg kg-1) or ICI 118551 (0.5 mg kg-1) and the potassium changes compared to those seen in control animals. The inotrope infusions caused a small and transient rise in plasma potassium (p less than 0.05) followed by a more profound hypokalaemia (p less than 0.05) sustained for the duration of the infusion. The potassium falls in the control animals were similar to those in the beta 1 and beta 2 blockade groups. The results suggest that beta 2 receptor stimulation cannot alone be responsible for dopamine and dobutamine induced hypokalaemia and a multiple receptor activation is postulated.
Smith
M
M
Department of Medicine, Middlesex Hospital, London, UK.
Drake
H F
HF
Corfield
D R
DR
Treasure
T
T
D000818:Animals; D001262:Atenolol / Q000494:pharmacology / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D004280:Dobutamine / Q000008:administration & dosage / Q000494:pharmacology*; D004285:Dogs; D004298:Dopamine / Q000008:administration & dosage / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D007008:Hypokalemia / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy*; D007262:Infusions, Intravenous; D011412:Propanolamines / Q000494:pharmacology / Q000627:therapeutic use*
D011412:Propanolamines; D004280:Dobutamine; C026777:ICI 118551; D001262:Atenolol; D004298:Dopamine