Opposite regulation by the beta-adrenoceptor-cyclic AMP system of synaptic plasticity in the medial and lateral amygdala in vitro.
The effects of beta-adrenoceptor activation on short-term potentiation in the medial and lateral amygdala were investigated using rat brain slice preparations in vitro. Application of tetanic stimulation (100 pulses at 100 Hz) induced only short-term potentiation under normal recording conditions. In the medial amygdala, when the same tetanic stimulation was applied in the presence of a beta-adrenoceptor agonist, isoproterenol, short-term potentiation was significantly enhanced and long-term potentiation was induced. Phenylephrine, an alpha-adrenoceptor agonist, did not affect short-term potentiation. The short-term potentiation-enhancing effect of isoproterenol was mimicked by forskolin, an adenylate cyclase activator, and was blocked by Rp-adenosine-3',5'-cyclic-monophosphothioate, an inhibitor of cyclic AMP-dependent protein kinase. On the other hand, in the lateral amygdala, isoproterenol suppressed short-term potentiation. The short-term potentiation-suppressing effect of isoproterenol was mimicked by forskolin, and was blocked by Rp-adenosine-3',5'-cyclic-monophosphothioate. These results suggest that the beta-adrenoceptor-cyclic AMP system plays a role in facilitating the induction of long-term potentiation in the medial amygdala, but suppresses synaptic plasticity in the lateral amygdala.
Watanabe
Y
Y
Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, University of Tokyo, Japan.
Ikegaya
Y
Y
Saito
H
H
Abe
K
K
D000262:Adenylyl Cyclases / Q000378:metabolism; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000679:Amygdala / Q000737:chemistry* / Q000201:enzymology / Q000502:physiology; D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000502:physiology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004594:Electrophysiology; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology*; D010656:Phenylephrine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D013569:Synapses / Q000737:chemistry*; D009435:Synaptic Transmission / Q000187:drug effects; D013999:Timolol / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D011943:Receptors, Adrenergic, beta; D005576:Colforsin; D010656:Phenylephrine; D013999:Timolol; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D000262:Adenylyl Cyclases; D007545:Isoproterenol