Video Experimental Relacionado
Updated: Jul 29, 2026
11:56
Historical View and Physiology Demonstration at the NMJ of the Crayfish Opener Muscle
Published on: November 9, 2009
Propiedades de los canales postsinápticos inducidos por la acetilcolina en diferentes fibras musculares de ranas
Nature
|May 14, 1981
Resumen
Este estudio revela distintas propiedades del canal del receptor de acetilcolina en las fibras musculares de las ranas. Estos hallazgos avanzan en nuestra comprensión de la transmisión neuromuscular a través de diferentes tipos de fibra.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Fisiología Muscular Fisiología Muscular
Sus antecedentes:
- Los músculos esqueléticos de las ranas tienen fibras rápidas y lentas, con tipos intermedios también presentes.
- Se conoce la acción de la acetilcolina (ACh) en los canales de fibra rápida, pero se comprende poco para otros tipos de fibra.
Objetivo del estudio:
- Para investigar la acción molecular de la acetilcolina (ACh) en diferentes tipos de fibras musculares de ranas.
- Para caracterizar un nuevo músculo de rana con múltiples fibras inervadas y capaces de potencial de acción.
Principales métodos:
- Registros electrofisiológicos de las membranas sinápticas.
- Análisis de las propiedades de los canales de entrada de acetilcolina (vida, conductancia).
Principales resultados:
- Identificó un músculo mandibular de rana donde la mayoría de las fibras se multiplican innervado y excitable.
- Se demostró que los canales inducidos por acetilcolina difieren en la vida útil y la conductancia a través de las fibras musculares rápidas, lentas y submaxiláreas.
Conclusiones:
- Los canales del receptor de acetilcolina exhiben una heterogeneidad significativa en diferentes tipos de fibras musculares de ranas.
- Esta diversidad en las propiedades de los canales puede ser la base de la especialización funcional en los sistemas neuromusculares anfibios.
Más Videos Relacionados
17:05Loading a Calcium Dye into Frog Nerve Endings Through the Nerve Stump: Calcium Transient Registration in the Frog Neuromuscular Junction
Published on: July 8, 2017
10:45Levator Auris Longus Preparation for Examination of Mammalian Neuromuscular Transmission Under Voltage Clamp Conditions
Published on: May 5, 2018
Videos de Conceptos Relacionados
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
01:25Cholinergic Receptors: Muscarinic
The pharmacological actions of acetylcholine are elicited via its binding to two families of cholinergic receptors or cholinoceptors, namely, muscarinic and nicotinic receptors. Muscarinic receptors are G protein-coupled receptors and have five subtypes, M1–M5. All mAChR subtypes are activated by acetylcholine and blocked by the antagonist, atropine.
The subtypes M1, M3, and M5 couple with the Gq subunit and activate the phospholipase C (PLC) activity, mobilizing intracellular Ca2+. Activation...
The subtypes M1, M3, and M5 couple with the Gq subunit and activate the phospholipase C (PLC) activity, mobilizing intracellular Ca2+. Activation...
01:29Neuromuscular Junction And Blockade
The site of chemical communication between a motor neuron and a muscle fiber is called the neuromuscular junction (NMJ). The end of the motor neuron at the NMJ divides into a cluster of synaptic end bulbs. The cytoplasm of these bulbs consists of synaptic vesicles enclosing acetylcholine molecules, the principal neurotransmitter released at the NMJ. The region opposite the synaptic bulb that ends in the muscle fiber is called the motor end plate, which has acetylcholine receptors. Within the...
01:24Generation of Action Potential in Skeletal Muscles
Every cell in the body maintains a membrane potential due to an uneven distribution of positive and negative charges across its plasma membrane. The membrane potential is measured in millivolts and quantifies the difference in charge across the membrane.
Like neurons, muscle cells are also regarded as excitable due to their capacity to change in response to stimuli, primarily due to voltage-gated ion channels embedded in their plasma membranes, which get activated by alterations in the cell's...
Like neurons, muscle cells are also regarded as excitable due to their capacity to change in response to stimuli, primarily due to voltage-gated ion channels embedded in their plasma membranes, which get activated by alterations in the cell's...
01:29Relaxation of Skeletal Muscles
The period of muscle contraction primarily influences the duration of stimulation at the neuromuscular junction (NMJ), the presence of free calcium ions in the sarcoplasm, and the availability of energy or ATP to support contractions.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...