Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions
1. The effects of different calcium channel blockers ω-agatoxin IVA (ω-Aga IVA), ω-conotoxin GVIA (ω-CgTx GVIA) and dihydropyridines) were tested on spontaneous and evoked transmitter release at embryonic and newborn rat neuromuscular junctions (NMJs). 2. The nerve-evoked transmitter release quantal...
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1999
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00223751_v514_n2_p533_RosatoSiri http://hdl.handle.net/20.500.12110/paper_00223751_v514_n2_p533_RosatoSiri |
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paper:paper_00223751_v514_n2_p533_RosatoSiri2023-06-08T14:50:26Z Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions calcium channel calcium ion dihydropyridine neurotransmitter nifedipine nitrendipine omega agatoxin IVA omega conotoxin GVIA potassium ion calcium channel unclassified drug voltage dependent calcium channel animal cell article calcium transport controlled study embryo embryo development miniature endplate potential muscle reinnervation neuromuscular synapse neurotransmitter release newborn nonhuman perinatal development priority journal rat animal tissue Article nerve potential postnatal development protein function stimulus response synaptic transmission Animals Animals, Newborn Calcium Channel Blockers Calcium Channels Calcium Channels, L-Type Calcium Channels, N-Type Diaphragm Embryo Evoked Potentials Motor Endplate Muscle, Skeletal Neuromuscular Junction Neurotransmitter Agents Nifedipine Nitrendipine omega-Agatoxin IVA omega-Conotoxin GVIA Peptides Phrenic Nerve Rats Rats, Wistar Spider Venoms Synaptic Transmission 1. The effects of different calcium channel blockers ω-agatoxin IVA (ω-Aga IVA), ω-conotoxin GVIA (ω-CgTx GVIA) and dihydropyridines) were tested on spontaneous and evoked transmitter release at embryonic and newborn rat neuromuscular junctions (NMJs). 2. The nerve-evoked transmitter release quantal content (m) was strongly reduced by the P/Q-type voltage-dependent calcium channel (VDCC) blocker ω-Aga IVA (100 nM) at newly formed endplates of embryos and 0- to 11-day-old rats, in agreement with the effect of this blocker on transmitter release at mature and reinnervating muscles. 3. ω-CgTx GVIA (1-5 μM), the N-type VDCC blocker, also caused a significant reduction in m at newly formed NMJs early in development (embryos and 0- to 4-day-old rats), while it was ineffective in more mature animals (5- to 11-day-old rats). 4. L-type channel blockers, nitrendipine (1 μM) and nifedipine (1 μM), did not significantly affect neurally evoked release at developing NMJs. However, nifedipine (10 μM) was able to increase m significantly at 0- to 4-day-old rat NMJs. 5. At developing NMJs, K+-evoked transmitter release was dependent on Ca2+ entry through VDCCs of the P/Q-type family (100 nM ω-Aga IVA reduced 70% of the K+-evoked miniature endplate potential frequency). N- and L-type VDCC blockers did not affect this type of release. 6. We conclude that at rat neuromuscular junctions the presynaptic calcium channel types involved in transmitter release undergo developmental changes during the early postnatal period. 1999 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00223751_v514_n2_p533_RosatoSiri http://hdl.handle.net/20.500.12110/paper_00223751_v514_n2_p533_RosatoSiri |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
calcium channel calcium ion dihydropyridine neurotransmitter nifedipine nitrendipine omega agatoxin IVA omega conotoxin GVIA potassium ion calcium channel unclassified drug voltage dependent calcium channel animal cell article calcium transport controlled study embryo embryo development miniature endplate potential muscle reinnervation neuromuscular synapse neurotransmitter release newborn nonhuman perinatal development priority journal rat animal tissue Article nerve potential postnatal development protein function stimulus response synaptic transmission Animals Animals, Newborn Calcium Channel Blockers Calcium Channels Calcium Channels, L-Type Calcium Channels, N-Type Diaphragm Embryo Evoked Potentials Motor Endplate Muscle, Skeletal Neuromuscular Junction Neurotransmitter Agents Nifedipine Nitrendipine omega-Agatoxin IVA omega-Conotoxin GVIA Peptides Phrenic Nerve Rats Rats, Wistar Spider Venoms Synaptic Transmission |
| spellingShingle |
calcium channel calcium ion dihydropyridine neurotransmitter nifedipine nitrendipine omega agatoxin IVA omega conotoxin GVIA potassium ion calcium channel unclassified drug voltage dependent calcium channel animal cell article calcium transport controlled study embryo embryo development miniature endplate potential muscle reinnervation neuromuscular synapse neurotransmitter release newborn nonhuman perinatal development priority journal rat animal tissue Article nerve potential postnatal development protein function stimulus response synaptic transmission Animals Animals, Newborn Calcium Channel Blockers Calcium Channels Calcium Channels, L-Type Calcium Channels, N-Type Diaphragm Embryo Evoked Potentials Motor Endplate Muscle, Skeletal Neuromuscular Junction Neurotransmitter Agents Nifedipine Nitrendipine omega-Agatoxin IVA omega-Conotoxin GVIA Peptides Phrenic Nerve Rats Rats, Wistar Spider Venoms Synaptic Transmission Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| topic_facet |
calcium channel calcium ion dihydropyridine neurotransmitter nifedipine nitrendipine omega agatoxin IVA omega conotoxin GVIA potassium ion calcium channel unclassified drug voltage dependent calcium channel animal cell article calcium transport controlled study embryo embryo development miniature endplate potential muscle reinnervation neuromuscular synapse neurotransmitter release newborn nonhuman perinatal development priority journal rat animal tissue Article nerve potential postnatal development protein function stimulus response synaptic transmission Animals Animals, Newborn Calcium Channel Blockers Calcium Channels Calcium Channels, L-Type Calcium Channels, N-Type Diaphragm Embryo Evoked Potentials Motor Endplate Muscle, Skeletal Neuromuscular Junction Neurotransmitter Agents Nifedipine Nitrendipine omega-Agatoxin IVA omega-Conotoxin GVIA Peptides Phrenic Nerve Rats Rats, Wistar Spider Venoms Synaptic Transmission |
| description |
1. The effects of different calcium channel blockers ω-agatoxin IVA (ω-Aga IVA), ω-conotoxin GVIA (ω-CgTx GVIA) and dihydropyridines) were tested on spontaneous and evoked transmitter release at embryonic and newborn rat neuromuscular junctions (NMJs). 2. The nerve-evoked transmitter release quantal content (m) was strongly reduced by the P/Q-type voltage-dependent calcium channel (VDCC) blocker ω-Aga IVA (100 nM) at newly formed endplates of embryos and 0- to 11-day-old rats, in agreement with the effect of this blocker on transmitter release at mature and reinnervating muscles. 3. ω-CgTx GVIA (1-5 μM), the N-type VDCC blocker, also caused a significant reduction in m at newly formed NMJs early in development (embryos and 0- to 4-day-old rats), while it was ineffective in more mature animals (5- to 11-day-old rats). 4. L-type channel blockers, nitrendipine (1 μM) and nifedipine (1 μM), did not significantly affect neurally evoked release at developing NMJs. However, nifedipine (10 μM) was able to increase m significantly at 0- to 4-day-old rat NMJs. 5. At developing NMJs, K+-evoked transmitter release was dependent on Ca2+ entry through VDCCs of the P/Q-type family (100 nM ω-Aga IVA reduced 70% of the K+-evoked miniature endplate potential frequency). N- and L-type VDCC blockers did not affect this type of release. 6. We conclude that at rat neuromuscular junctions the presynaptic calcium channel types involved in transmitter release undergo developmental changes during the early postnatal period. |
| title |
Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| title_short |
Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| title_full |
Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| title_fullStr |
Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| title_full_unstemmed |
Calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| title_sort |
calcium channels coupled to neurotransmitter release at neonatal rat neuromuscular junctions |
| publishDate |
1999 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00223751_v514_n2_p533_RosatoSiri http://hdl.handle.net/20.500.12110/paper_00223751_v514_n2_p533_RosatoSiri |
| _version_ |
1768543168936017920 |