Smooth Muscle Contraction

Описание: Understand Smooth Muscle Physiology with Dr. Faiza
Dive into a concise, high-yield overview of smooth muscle structure, types, and the unique mechanisms that power its contraction and relaxation. Compare smooth vs skeletal muscle, learn how Ca²⁺, calmodulin, and MLCK drive force, and master hallmark phenomena like the latch mechanism and stress–relaxation. Ideal for exam prep and clinical grounding.

🔬 Key Topics Covered:
• Smooth Muscle Types: multi-unit vs unitary (single-unit), gap junctions, diffuse innervation
• Ultrastructure: dense bodies, side-polar myosin arrangement, caveolae, SR role
• Contraction Pathway: extracellular and SR Ca²⁺, Ca²⁺–calmodulin, MLCK activation, cross-bridge cycling
• Relaxation Pathway: SERCA, plasmalemmal Ca²⁺ pumps/exchangers, myosin light-chain phosphatase
• Functional Modes: tonic vs phasic contraction, length–tension features, high force at broad lengths
• Energy & Efficiency: slow ATPase, economical contractions, sustained tone
• Signature Phenomena: latch mechanism (low-energy sustained tension) and stress–relaxation (and reverse)
• Organ Examples: GI tract, bladder, uterus, vascular smooth muscle, airways and pupil control

🎓 Learning Objectives:
• Differentiate multi-unit and unitary smooth muscle and their patterns of activation.
• Explain Ca²⁺ sources, Ca²⁺–calmodulin–MLCK signaling, and MLCP in relaxation.
• Describe latch mechanism and stress–relaxation with clinical examples (bladder filling, vascular tone).
• Contrast smooth vs skeletal muscle in force production, velocity, and energy economy.

💡 Clinical Relevance:
• Interpret bladder/vascular behavior via stress–relaxation and tonic tone.
• Anticipate drug and hormone effects that modulate Ca²⁺ entry or MLCK/MLCP balance.
• Apply concepts to GI motility disorders, asthma/bronchospasm, dysmenorrhea, and hypertension.

📚 Learning Resources:
Phone: +92 310 7990649
Email: [email protected]

Website: https://www.medicoseacademics.com/

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Dr. Faiza
Assistant Professor of Physiology
MBBS (AIMC, lahore, Best Graduate)
FCPS (Physiology)
CHPE (Certificate in Health Professional Education)
DHPE (Diploma in Health Professional Education)
DHPE (Masters in Health Professional Education)
MBA (Masters of Business Administration)
MPH (Masters of Public Health)
LinkedIn:   / faizaikram  

Tags:
Smooth Muscle Physiology, Multi Unit Smooth Muscle, Unitary Smooth Muscle, Gap Junctions, Dense Bodies, Caveolae, Calmodulin, Myosin Light Chain Kinase MLCK, Myosin Light Chain Phosphatase MLCP, SERCA, Extracellular Calcium Entry, Latch Mechanism, Stress Relaxation, Tonic vs Phasic Contraction, Vascular Smooth Muscle, GI Motility, Bladder Physiology, Uterine Contraction, Airway Smooth Muscle, Medical Education