https://stream.echo6.co/videos/watch/f19948f2-77b8-4756-b7df-a6a27e3ba190 Official Ninja Nerd Website: https://ninjanerd.org Ninja Nerds! In this lecture, Professor Zach Murphy explores smooth muscle's structure, function, and regulation. We begin by contrasting smooth muscle with skeletal and cardiac muscle, emphasizing its non-striated appearance, single centrally located nuclei, and spindle-shaped cells. The discussion covers the organization of actin and myosin filaments anchored to dense bodies, allowing contraction in multiple directions and making smooth muscle ideal for maintaining tone and sustaining contractions. We then detail the excitation–contraction coupling process in smooth muscle, highlighting the role of calcium influx through voltage-gated and ligand-gated channels, calmodulin activation, and subsequent myosin light-chain kinase (MLCK) activity. The lecture explains how smooth muscle contraction is regulated by the autonomic nervous system input and local factors such as stretch, pH, and chemical mediators. We also cover the differences between single-unit and multi-unit smooth muscle, including the gastrointestinal tract, blood vessels, and the iris. Finally, we connect these principles to real physiological contexts, showing how smooth muscle adapts to varying functional demands such as vasodilation, peristalsis, and regulation of airway resistance. Enjoy the lecture and support us below! 🌐 Official Links Website: https://www.ninjanerd.org Podcast: https://podcast.ninjanerd.org Store: https://merch.ninjanerd.org 📱 Social Media https://www.tiktok.com/@ninjanerdlectures https://www.instagram.com/ninjanerdlectures https://www.facebook.com/ninjanerdlectures https://x.com/ninjanerdsci/ https://www.linkedin.com/company/ninja-nerd/ 💬 Join Our Community Discord: https://discord.gg/3srTG4dngW #ninjanerd #SmoothMuscle #Musculoskeletal Wed, 15 Apr 2026 11:34:20 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/f19948f2-77b8-4756-b7df-a6a27e3ba190 All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.