Contribution of α4β2 nAChR in nicotine-induced intracellular calcium response and excitability of MSDB neurons
| Autor: | Chengbiao Lu, Yunpeng Zhang, JianGang Wang, Ran Wang, Wang Yang, Qian Zhang, Yali Wang |
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| Rok vydání: | 2014 |
| Předmět: |
Male
Nicotine Patch-Clamp Techniques alpha7 Nicotinic Acetylcholine Receptor chemistry.chemical_element Nicotinic Antagonists Cholinergic Agonists Receptors Nicotinic Neurotransmission Calcium Diagonal Band of Broca Calcium in biology Membrane Potentials Tissue Culture Techniques chemistry.chemical_compound medicine Animals Nicotinic Agonists Patch clamp Egtazic Acid Molecular Biology Calcium Chelating Agents Calcium signaling Neurons Mice Inbred BALB C Chemistry General Neuroscience Dihydro-beta-Erythroidine Acetylcholine EGTA Nicotinic acetylcholine receptor nervous system Neurology (clinical) Neuroscience Developmental Biology medicine.drug |
| Zdroj: | Brain Research. 1592:1-10 |
| ISSN: | 0006-8993 |
| Popis: | The neurons of medial septal diagonal band of broca (MSDB) project to hippocampus and play an important role in MSDB-hippocampal synaptic transmission, plasticity and network oscillation. Nicotinic acetylcholine receptor (nAChR) subunits, α4β2 and α7 nAChRs, are expressed in MSDB neurons and permeable to calcium ions, which may modulate the function of MSDB neurons. The aims of this study are to determine the roles of selective nAChR activation on the calcium responses and membrane currents in MSDB neurons. Our results showed that nicotine increased calcium responses in the majority of MSDB neurons, pre-treatment of MSDB slices with a α4β2 nAChR antagonist, DhβE but not a α7 nAChR antagonist, MLA prevented nicotine-induced calcium responses. The whole cell patch clamp recordings showed that nicotine-induced inward current and acetylcholine (ACh) induced-firing activity can be largely reduced or prevented by DhβE in MSDB neurons. Surprisingly, post-treatment of α4β2 or α7 nAChR antagonists failed to block nicotine׳s role, they increased calcium responses instead. Application of calcium chelator EGTA reduced calcium responses in all neurons tested. These results suggest that there was a subtype specific modulation of nAChRs on calcium signaling and membrane currents in MSDB neurons and nAChR antagonists were also able to induce calcium responses involving a distinct mechanism. |
| Databáze: | OpenAIRE |
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