Activation of α₁-adrenoceptors enhances excitatory synaptic transmission via a pre- and postsynaptic protein kinase C-dependent mechanism in the medial prefrontal cortex of rats.
The physiological effects of α₁-adrenoceptors (α₁-ARs) have been examined in many brain regions. However, little is known about the mechanism of modulation on synaptic transmission by α₁-ARs in the medial prefrontal cortex (mPFC). The present study investigated how α₁-AR activation regulates glutamatergic synaptic transmission in layer V/VI pyramidal cells of the rat mPFC. We found that the α₁-AR agonist phenylephrine (Phe) induced a significant enhancement of the amplitude and frequency of miniature excitatory postsynaptic currents (mEPSCs). The facilitation effect of Phe on the frequency of mEPSCs involved a presynaptic protein kinase C-dependent pathway. Phe produced a significant enhancement on the amplitude of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPA-R)- and N-methyl-D-aspartic acid receptor (NMDA-R)-mediated evoked excitatory postsynaptic currents (eEPSCs). Phe enhanced inward currents evoked by puff application of glutamate or NMDA. The Phe-induced facilitation of AMPA-R- and NMDA-R-mediated eEPSCs required, in part, postsynaptic Gq , phospholipase C and PKC. These findings suggest that α₁-AR activation facilitates excitatory synaptic transmission in mPFC pyramidal cells via both pre- and post-synaptic PKC-dependent mechanisms.
Institute of Neurobiology & State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Fudan University, Shanghai, 200032, China.
Fei
F
Luo
Hua
H
Tang
Bao-ming
BM
Li
Si-hai
SH
Li
D058646:Adrenergic alpha-1 Receptor Agonists / Q000494:pharmacology; D000818:Animals; D019706:Excitatory Postsynaptic Potentials; D055369:Miniature Postsynaptic Potentials; D010656:Phenylephrine / Q000494:pharmacology; D017397:Prefrontal Cortex / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D011493:Protein Kinase C / Q000378:metabolism*; D017966:Pyramidal Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000378:metabolism; D018340:Receptors, Adrenergic, alpha-1 / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013569:Synapses / Q000378:metabolism* / Q000502:physiology
D058646:Adrenergic alpha-1 Receptor Agonists; D018091:Receptors, AMPA; D018340:Receptors, Adrenergic, alpha-1; D016194:Receptors, N-Methyl-D-Aspartate; D010656:Phenylephrine; D011493:Protein Kinase C
excitatory synaptic transmission; medial prefrontal cortex; rat; α1-Adrenoceptor