Propranolol reduces rat dopamine-beta-hydroxylase activity and catecholamine levels.
Propranolol treatment (1 mg/kg i.p. twice daily for 8 days) reduced atrial dopamine-beta-hydroxylase (D beta H) activity by 60.5% and lung D beta H activity by 53.5% but did not alter ventricle D beta H activity. Propranolol also significantly reduced atrial noradrenaline (NA) by 66.3%, adrenaline (A) by 40%, dopamine (DA) by 72.4% and lung NA by 46.6% but did not change plasma or cardiac ventricle catecholamines. The addition of propranolol (10(-6) M) to cardiac and lung tissue homogenates in vitro did not inhibit tissue D beta H activities. The results suggest that chronic propranolol treatment inhibits NA synthesis and support the hypothesis of a centrally induced inhibition of sympathetic activity caused by beta-adrenoceptor blockade.
Elayan
H
H
Department of Medicine, University of California, San Diego Medical Center 92103-8341.
Kennedy
B
B
Ziegler
M G
MG
D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D004299:Dopamine beta-Hydroxylase / Q000037:antagonists & inhibitors*; D006321:Heart / Q000187:drug effects*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D002395:Catecholamines; D011433:Propranolol; D004299:Dopamine beta-Hydroxylase