Nerve MUSCLE PHYSIOLOGY Molecular Mechanism Of Muscle Contraction

  • Slides: 29
Download presentation
Nerve MUSCLE PHYSIOLOGY

Nerve MUSCLE PHYSIOLOGY

Molecular Mechanism Of Muscle Contraction • Sliding filament mechanism • Walk along theory •

Molecular Mechanism Of Muscle Contraction • Sliding filament mechanism • Walk along theory • Ratchet theory

Walk Along Theory

Walk Along Theory

Interaction B/W Actin & Myosin

Interaction B/W Actin & Myosin

Walk Along (Ratchet) Theory

Walk Along (Ratchet) Theory

Relaxed & Contracted

Relaxed & Contracted

NEUROMUSCULAR JUNCTION

NEUROMUSCULAR JUNCTION

Motor Unit Single Motor Neuron & all Muscle Fibers it innervates constitute a single

Motor Unit Single Motor Neuron & all Muscle Fibers it innervates constitute a single Motor Unit. α- motor N

Neuro. Muscular Junction

Neuro. Muscular Junction

Release of Acetylcholine

Release of Acetylcholine

Ligand Gated Channel (Acetylcholine) Closed Open

Ligand Gated Channel (Acetylcholine) Closed Open

• Safety factor for transmission at the Neuromuscular junction. • Fatigue of Neuromuscular

• Safety factor for transmission at the Neuromuscular junction. • Fatigue of Neuromuscular Junction

Myasthenia Gravis • 1 in every 20, 000 persons. • Antibodies against acetylcholine receptors.

Myasthenia Gravis • 1 in every 20, 000 persons. • Antibodies against acetylcholine receptors. • Autoimmune disease. • Muscle paralysis ---- inability of neuromuscular • junction to transmit enough signals. Neostigmine ---- anticholinesterase drug.

Sarcoplasmic Reticulum T-Tubule & Longitudinal Tubule

Sarcoplasmic Reticulum T-Tubule & Longitudinal Tubule

T Sarcoplasmic Reticulum T-Tubule & Longitudinal Tubule T L

T Sarcoplasmic Reticulum T-Tubule & Longitudinal Tubule T L

Sarcoplasmic Reticulum(T-tubule) DHP & Ryanidin Receptor (Hypothetical Model)

Sarcoplasmic Reticulum(T-tubule) DHP & Ryanidin Receptor (Hypothetical Model)

A. P entering the Sarcoplasmic Reticulum causing release of Ca++ ions

A. P entering the Sarcoplasmic Reticulum causing release of Ca++ ions

Excitation-Contraction coupling “The process by which the depolarization of the muscle fiber initiates contraction”

Excitation-Contraction coupling “The process by which the depolarization of the muscle fiber initiates contraction”

Sequence of Events in contraction of Muscle u Stimulation of Motor Neuron. u Release

Sequence of Events in contraction of Muscle u Stimulation of Motor Neuron. u Release of neurotransmitter (Acetylcholine) at Motor End-plate. u Binding of Ach to Nicotinic Receptors. u Increased Na+ conductance through Ach Channels u Generation of end-plate potential u Generation of Action Potential in Muscle Fiber

Sequence of Events in Contraction u Inward spread of depolarization along T-Tubule. Sensing by

Sequence of Events in Contraction u Inward spread of depolarization along T-Tubule. Sensing by DHP receptors & opening of Rayanidine receptors in terminal cisterns. u Release of Ca++ from terminal cistern of Sarcoplasmic Reticulum and diffusion to myofilaments u Binding of Ca++ to Troponin-C, uncovering Myosin binding on Actin filaments u Formation of Cross linkages between Actin & Myosin leading to sliding of thin on thick filaments, producing movement of Z-lines toward the centre

Steps involved in Relaxation of Muscle u ATP attaches to Myosin head Ca++ Pumped

Steps involved in Relaxation of Muscle u ATP attaches to Myosin head Ca++ Pumped Back in Sarcoplasmic Reticulum. (Ca++ Mg++ ATPase Pump always On ) u Release of Ca++ from Troponin u u Cessation of Interaction between Actin & Myosin filaments

MECHANISM OF MUSCLE CONTRACTION AND RELAXATION Muscle contractionMECHANISM OF MUSCLE CONTRACTION AND RELAXATION Muscle contraction
MECHANISM OF MUSCLE CONTRACTION AND RELAXATION Muscle contractionMECHANISM OF MUSCLE CONTRACTION AND RELAXATION Muscle contraction
MUSCLE CONTRACTION Muscle Contraction Muscle contractions begin withMUSCLE CONTRACTION Muscle Contraction Muscle contractions begin with
Muscle Physiology Muscle activity The muscle contraction isMuscle Physiology Muscle activity The muscle contraction is
Physiology of Muscle Contraction Physiology of skeletal musclePhysiology of Muscle Contraction Physiology of skeletal muscle
MUSCLE CONTRACTION Basis of Muscle Contraction Actin filamentsMUSCLE CONTRACTION Basis of Muscle Contraction Actin filaments
Applied Nerve Muscle Physiology Nerve Conduction Study NCSApplied Nerve Muscle Physiology Nerve Conduction Study NCS
Applied Nerve Muscle Physiology Nerve Conduction Study NCSApplied Nerve Muscle Physiology Nerve Conduction Study NCS
Muscle Anatomy and Contraction Muscle Music Muscle TermsAnatomyMuscle Anatomy and Contraction Muscle Music Muscle TermsAnatomy
Muscle Contraction Muscle structure Proteins in muscle SlidingMuscle Contraction Muscle structure Proteins in muscle Sliding
Muscle Anatomy and Contraction Muscle Music Muscle TermsAnatomyMuscle Anatomy and Contraction Muscle Music Muscle TermsAnatomy
MUSCLE TISSUE Muscle Contraction TYPES OF MUSCLE TISSUEMUSCLE TISSUE Muscle Contraction TYPES OF MUSCLE TISSUE
Molecular mechanism of muscle contraction Sliding Filament theoryMolecular mechanism of muscle contraction Sliding Filament theory
Muscle Physiology Stimulus Frequency and muscle contraction EnergyMuscle Physiology Stimulus Frequency and muscle contraction Energy
Muscle Physiology Dynamics of Muscle Contraction MMHS AnatomyMuscle Physiology Dynamics of Muscle Contraction MMHS Anatomy
Physiology of Skeletal Muscle Contraction The Muscle ActionPhysiology of Skeletal Muscle Contraction The Muscle Action
Muscle Physiology Twitch Contraction of muscle in responseMuscle Physiology Twitch Contraction of muscle in response
Skeletal muscle physiology Muscle contraction in the bodySkeletal muscle physiology Muscle contraction in the body
Force of Muscle Contraction Force of contraction dependsForce of Muscle Contraction Force of contraction depends
Contraction of a Skeletal Muscle fiber contraction isContraction of a Skeletal Muscle fiber contraction is
Skeletal muscle contraction Contraction force and tension SlidingSkeletal muscle contraction Contraction force and tension Sliding
Force of Muscle Contraction The force of contractionForce of Muscle Contraction The force of contraction
EXCITATION CONTRACTION COUPLING EXCITATION CONTRACTION COUPLING MOLECULAR BASISEXCITATION CONTRACTION COUPLING EXCITATION CONTRACTION COUPLING MOLECULAR BASIS
Neural Control of Muscle Contraction A Nerve SupplyNeural Control of Muscle Contraction A Nerve Supply