Carteolol is a useful tool to prove the tonically functioning nature of presynaptic beta-adrenoceptors on peripheral noradrenergic neurons but not on central catecholaminergic neurons.
Effects of carteolol on norepinephrine (NE) release were studied at 2 Hz mainly in rat hypothalamic slices. Isoproterenol at 1 and 10 nM concentration-dependently facilitated NE release. Isoproterenol (10 nM)-induced facilitation was antagonized by 1 and 10 nM dl-carteolol, but not antagonized by 1 nM d-carteolol. dl-Carteolol alone at 1 nM to 10 microM did not inhibit NE release. In brainstem slices, 10 nM isoproterenol also facilitated NE release, and this facilitation tended to be antagonized by 1 nM dl-carteolol. Nanomolar concentrations of carteolol stereoselectively antagonized isoproterenol-induced facilitation of NE release via presynaptic beta-adrenoceptors in rat hypothalamic slices.
Ohno
K
K
Department of Pharmacology, Yokohama City University School of Medicine, Japan.
Nakamura
S
S
Goshima
Y
Y
Misu
Y
Y
D000319:Adrenergic beta-Antagonists; D000818:Animals; D001933:Brain Stem / Q000187:drug effects / Q000502:physiology; D002354:Carteolol; D002395:Catecholamines / Q000502:physiology*; D004558:Electric Stimulation; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D007545:Isoproterenol / Q000037:antagonists & inhibitors; D008297:Male; D009474:Neurons / Q000187:drug effects*; D009638:Norepinephrine / Q000502:physiology*; D011412:Propanolamines; D051381:Rats; D011919:Rats, Inbred Strains; D013237:Stereoisomerism
D000319:Adrenergic beta-Antagonists; D002395:Catecholamines; D011412:Propanolamines; D002354:Carteolol; D007545:Isoproterenol; D009638:Norepinephrine