Carbachol induces a form of long-term potentiation in lateral amygdala.
We examined the effects of carbachol, a muscarinic acetylcholine receptor agonist, on excitatory synaptic transmission at thalamo-amygdala synapses in rat brain slices. The application of a low concentration of carbachol (0.25 microM) produced a form of long-term potentiation (cLTP) and a transient suppression of synaptic responses, which was blocked by a muscarinic receptor antagonist, atropine (10 microM). M2 receptor agonist produced only a transient suppression, whereas M1 receptor agonist induced both a transient suppression and a long-term potentiation. Induction of cLTP required simultaneous low-frequency afferent stimulation, and was also dependent upon the activation of NMDA receptors. SQ22536 (50 microM), an adenylyl cyclase inhibitor completely blocked cLTP. Consistently, pretreatment with a maximal concentration of forskolin (10 microM) reduced cLTP.
Park
Eun-Jin
EJ
Department of Biological Sciences, College of Natural Sciences, Inha University, 253 Yong-Hyun Dong, Nam-Gu, Inchon 402-751, South Korea.
Nam
Ryoung-Hee
RH
Choi
Sukwoo
S
Lee
Chang-Joong
CJ
D000109:Acetylcholine / Q000378:metabolism*; D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism; D000344:Afferent Pathways / Q000502:physiology; D000679:Amygdala / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology*; D018679:Cholinergic Agonists / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects* / Q000502:physiology; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects* / Q000502:physiology; D013788:Thalamus / Q000502:physiology
D000067956:Adenylyl Cyclase Inhibitors; D018679:Cholinergic Agonists; D004791:Enzyme Inhibitors; D018727:Muscarinic Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D005576:Colforsin; D001285:Atropine; D002217:Carbachol; D000262:Adenylyl Cyclases; D000109:Acetylcholine