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Harvard-MIT Division of Health Sciences and Technology HST.523J: Cell-Matrix Mechanics Prof. Myron Spector Massachusetts Institute of Technology Harvard Medical School Brigham and Women’s Hospital VA Boston Healthcare System 2.785j/3.97J/BEH.411/HST523J2.785j/3.97J/BEH.411/HST523J MUSCLEMUSCLE CONTRACTIONCONTRACTION M. Spector, Ph.D. Diagrams of muscle fiber structure removed for copyright reasons. See, for example, Slides 32-37 in Chapter 6 of http://kinesiology.boisestate.edu/rvhp/ Figure by MIT OCW. 6-5 Diagrams removed for copyright reasons. See the actin/myosin animations at http://www.sci.sdsu.edu/movies/actin_myosin_gif.html http://www.accessexcellence.org/AB/GG/muscle_Contract.html Diagram removed for copyright reasons. (A) The myosin and actin filaments of a sarcomere overlap with the same relative polarity on either side of the midline. Recall that actin filaments are anchored by their plus ends to the Z disc and that myosin filaments are bipolar. (B) During contraction, the actin and myosin filaments slide past each other without shortening. The sliding motion is driven by the myosin heads walking toward the plus end of the adjacent actin filament. Diagram removed for copyright reasons. See Figure 18-29 in Lodish et al. Molecular Cell Biology 4th ed. Available online at PubMed Bookshelf, http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=Books Sliding filament model of contraction in striated muscle. In the presence of ATP and Ca+2 the myosin heads, extending from the thick filaments, pivot pulling the actin thin filaments towards the center. The thin filaments are anchored and thus the movement shortens the sarcomere length. http://www.bris.ac.uk/Depts/Physiology/ugteach/ugindex/m1_index/nm_tension/page1.htm Diagrams removed for copyright reasons. Figure 1 Length-tension relation for skeletal muscle Figure 2 Experimental setup required to determine length-tension relation of muscle http://academic.uofs.edu/faculty/kosmahle1/courses/pt245/lngthten.htm Copyright 2000, Edmund M. Kosmahl. Used with permission..

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Characterization of Cecal Smooth Muscle Contraction in Laying Hens
veterinary sciences Communication Characterization of Cecal Smooth Muscle Contraction in Laying Hens Katrin Röhm 1, Martin Diener 2 , Korinna Huber 1 and Jana Seifert 1,* 1 Institute of Animal Science, University of Hohenheim, 70593 Stuttgart, Germany; [email protected] (K.R.); [email protected] (K.H.) 2 Institute of Veterinary Physiology and Biochemistry, Justus-Liebig University, 35392 Gießen, Germany; [email protected] * Correspondence: [email protected] Abstract: The ceca play an important role in the physiology of the gastrointestinal tract in chickens. Nevertheless, there is a gap of knowledge regarding the functionality of the ceca in poultry, especially with respect to physiological cecal smooth muscle contraction. The aim of the current study is the ex vivo characterization of cecal smooth muscle contraction in laying hens. Muscle strips of circular cecal smooth muscle from eleven hens are prepared to investigate their contraction ex vivo. Contraction is detected using an isometric force transducer, determining its frequency, height and intensity. Spontaneous contraction of the chicken cecal smooth muscle and the inﬂuence of buffers (calcium-free buffer and potassium-enriched buffer) and drugs (carbachol, nitroprusside, isoprenaline and Verapamil) affecting smooth muscle contraction at different levels are characterized. A decrease in smooth muscle contraction is observed when a calcium-free buffer is used. Carbachol causes an increase in smooth muscle contraction, whereas atropine inhibits contraction. Nitroprusside, isoprenaline and Verapamil result in a depression of smooth muscle contraction. In conclusion, the present results conﬁrm a similar contraction behavior of cecal smooth muscles in laying hens as Citation: Röhm, K.; Diener, M.; shown previously in other species.
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Back-To-Basics: the Intricacies of Muscle Contraction
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Muscle Physiology Dr
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Spinal Reflexes
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Chapter 7 Excitation of Skeletal Muscle: Neuromuscular Transmission and Excitation-Contraction Coupling
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Coming of Age Or Midlife Crisis? Erick O
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The Mechanism of Muscle Contraction
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Histology of Muscle Tissue
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Muscle Contraction
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A Biochemical Analysis Beyond the Muscle Contraction and Its Relation with Isaac Syndrome Valdemir Aquino De Freitas Neto*
ISSN: 2643-4571 Neto et al. Int J Rare Dis Disord 2020, 3:028 DOI: 10.23937/2643-4571/1710028 Volume 3 | Issue 2 International Journal of Open Access Rare Diseases & Disorders REVIEW ARTICLE A Biochemical Analysis beyond the Muscle Contraction and its Relation with Isaac Syndrome Valdemir Aquino de Freitas Neto* Colégio GGE, Brazil Check for updates *Corresponding author: Valdemir Aquino de Freitas Neto, Colégio GGE, Jaboatão dos Guararapes, Pernambuco, Brazil inside the cell induces the Na+ channel to close eventu- Abstract ally, the K+ channels to open and, then, the K+ ions flow Isaac Syndrome is an autoimmune disease related to the in- from inside to outside the cell membrane, causing the voluntary contraction of skeletal muscles. The author, thus, is going to connect it with the process of muscle contraction repolarization of sarcolemma [1]. Through the action through a biochemical study, analysing the pathway from potential process, the impulse is able to follow the signal a nervous impulse to the open of voltage-gated Potassium to a motor neuron, consuming energy since the ATPase channels and the releasing of Ca2+ on myofibrils. This paper hydrolyses the ATP into ADP + Pi, releasing energy to intends to introduce this rare disease and to induce further + + researches in order to find a cure. restore the concentration of Na and K against the con- centration gradient by active transport. Also, in muscle Keywords cells, that action potential is called end-plate potential. Isaac Syndrome, Muscle contraction, Nervous impulse, Ca2+, Voltage-gated Potassium channels That process can go wrong if the nervous impulse ac- tivates the pump with no order of the brain and this is Abbreviations the main point around Isaac Syndrome or Neuromyoto- Na+: Sodium Cation; K+: Potassium Cation; ATP: Adenosine nia.
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