Thick filaments in unstretched mammalian smooth muscle.
D000818:Animals; D006168:Guinea Pigs; D006652:Histological Techniques; D008642:Mesenteric Veins / Q000033:anatomy & histology; D008854:Microscopy, Electron; D009130:Muscle, Smooth / Q000033:anatomy & histology*; D009210:Myofibrils; D011817:Rabbits; D013194:Staining and Labeling