Beta1-adrenergic receptor mediation in the lichen glucan PB-2-induced enhancement of long-term potentiation in the rat dentate gyrus in vivo.
The mechanism underlying the enhancement of long-term potentiation (LTP) induced by the systemic administration of PB-2, an alpha(1-3)(1-4)glucan-containing fraction extracted from the lichen Flavoparmelia baltimorensis and a putative LTP-enhancing agent, was investigated in the rat dentate gyrus in vivo. Particular attention was paid to the role of adrenaline beta-receptors. An intravenous (i.v.) injection of PB-2 enhanced the induction of LTP, which was in turn inhibited by an i.v. injection of the adrenaline beta1-receptor antagonist atenolol. An intracerebroventricular injection of atenolol did not affect the induction of LTP, but completely suppressed the PB-2-induced enhancement of LTP. The infusion of atenolol into the recording site attenuated the PB-2-induced facilitation of LTP. These results suggest that the adrenaline beta1-receptors contribute to the enhancement of LTP induced by the systemic administration of PB-2, and that the functional beta1-receptors are located both centrally and peripherally.
Edagawa
Yoshikuni
Y
Department of Pharmacology, College of Pharmacy, Nihon University, 7-7-1 Narashinodai, Funabashi, Chiba 247-8555, Japan.
Yamaguchi
Chie
C
Saito
Hiroshi
H
Takeda
Tadahiro
T
Shimizu
Noriko
N
Narui
Takao
T
Shibata
Shoji
S
Ito
Yoshihisa
Y
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001262:Atenolol / Q000494:pharmacology; D018891:Dentate Gyrus / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D008011:Lichens / Q000737:chemistry*; D017774:Long-Term Potentiation / Q000187:drug effects* / Q000502:physiology; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011941:Receptors, Adrenergic / Q000187:drug effects* / Q000378:metabolism; D047071:beta-Glucans / Q000494:pharmacology*
D000319:Adrenergic beta-Antagonists; D010936:Plant Extracts; D011941:Receptors, Adrenergic; D047071:beta-Glucans; D001262:Atenolol