1. SLIDING FILAMENT MECHANISM Anis A. Makky, drg, MKes Oral Biology Dept. - Dentistry Faculty Airlangga University Surabaya, May 07, 2009

2. MUSCLE  skeletal muscle  smooth muscle  cardiac muscle

3. SKELETAL MUSCLE  muscle fibers  contractile protein  no extracellular calcium

4. CONTRACTILE PROTEIN  actin : actin troponin I, C, T tropomyosin  myosin  titin  nebulin

8. SLIDING FILAMENT MECHANISM

13. Figure 12-11a: Excitation-contraction coupling

14. Figure 12-11b: Excitation-contraction coupling

16. Cross-Bridge Formation in Muscle Contraction

19. Receptors in Muscle Muscle spindle –Detect dynamic and static changes in muscle length –Stretch reflex Stretch on muscle causes reflex contraction Golgi tendon organ (GTO) –Monitor tension developed in muscle –Prevents damage during excessive force generation Stimulation results in reflex relaxation of muscle

20. Muscle Spindle

21. Golgi Tendon Organ

22. Central –"Feeling" –Lactic acid Peripheral –Glycogen depletion –Ca 2+ interference –High P i levels –ECF high K + –ACh depletion Muscle Fatigue: Causes not well known Figure 12-14: Locations and possible causes of muscle fatigue