제 10 강 Muscular tissue in general 筋肉組織근육조직 (2) (2) T-tubules/ Sarcoplasmic reticulum/ Sarcosomes T 작은관 / 근육소포체 / 근육미토콘드리아 2) Smooth muscle 평활근 - Quite different in contractile apparatus 수축성장치에서완전히다르다 - Abundant parallel thin filament 풍부한평행의미세섬유 But, rare and usually absent in thick filaments 그러나, 두꺼운섬유가적고보통결여 - Actin as thin filament - Fugiform densities 방추형밀집 (Electron-dense bodies) - Opposite direction of actin filaments? 액틴섬유의마주보는방향? Analogous to Z line in skeletal muscle, ie., Z-line equivalent 골격근에서 Z 라인과유사함 - Within the central sarcoplasm and adjacent to the sarcolemma 근육세포막주위에있고근육세포질중앙에위치함 - Purified H- meromyosin? H- meromyosin을제거? Myosin Only half the actin-myosin ratio in the skeletal muscle
오직골격근에서만액틴 - 미오신비율이반이다 Different in activity 활동면이다르다 - Contraction units of smooth muscle 평활근에서수축단위 (Fig.) - actin and myosin filaments - intermediate filaments( desmin, vimentin) 중간섬유 - dense body : contain alpha-actinin - Visceral smooth muscle 내장의평활근 : large sheets such as those found in the walls of hollow viscera 그것과같은얇은판박들은속이빈내장의내벽들안에서찾을수있다. (intestine, uterus, ureters) ( 장, 자궁, 수뇨관 ) : abundant gap junctions and relatively poor nerve supply 간극연접이풍부하고비교적신경전달이부족하다. syncytial fashion 융합체 Multiunit smooth muscle 다단위평활근 : rich innervation 신경분포가풍부하다. produce precise and graded contractions 정확하고등급이나뉜수축을생산한다. Sarcoplasmic reticulum and transverse T tubule system 근내형질세망과가로소관계통 - A non-filamentous sarcoplasm 섬유가없는근내형질 Control and metabolism of the contractile processes 수축돌기의
제어와물질대사와관련있다 a. Sarcoplasmic reticulum 근소포체 b. Transverse tubular system (T-system) 가로소관계통 c. Mitochondria d. Glycogen granules / Lipid droplets 글리코겐과립 / 지질방울 ( 에너지성분 ) 1) Sarcoplasmic reticulum of skeletal muscle fibre 골격근섬유의소포체 (Fig.) - A ser 활면소포체가하나존재 ( 세포당 ) - regulates calcium flow rapid contraction and relaxation cycles 칼슘이온의흐름을조절하여근육의수축과이완이빠르게일어나게한다 - 2 sets of longitudinally oriented sarcotubules 가로형근육섬유로두군대에존재 Surrounding each myofibril 근육원섬유의주변에존재 (1) One set of sarcotubles 첫번째 sarcotubles - Surrounding at the level of the A band A 띠주변에존재 Anastomosis and then a network formation at the center of the sarcomere (M-line region) 근원섬유마디의가운데에망상으로생성 (M 선지역 ) - Anastomosis and then formation of a terminal cisternae at each A-I junction A띠와 I띠사이 (A-I 연접 ) 에존재하며, 종말수조 (terminal
cisternae) 의형태 ( 복잡한망구조 ) (2) Another set of sarcotubules 다른 sarcotubles - Surrounding at the level of the I band I 띠주변에존재 - Also the formation of terminal cisterna at each junction 각각의연접에종말수조형태로존재 Resultantly, a pair of terminal cisternae at each A-I junction 결과적으로각각의 A-I 연접에는한쌍의종말수조가존재 2) Transverse tubular system or T-system (Fig.) 가로소관계통 - Multiple, slender tubular invagination of the sarcolemma ie., T-tubules 근형질막이손가락모양으로함입되어복잡하게연결되어있는그물구조 Transverse penetration into the depths of each myofibre 각각의근원섬유안으로가로방향으로함입되어있는상태 Free anastomosis within the depths of each myofibre with other T-tubules 근원섬유내에서다른가로소관들과망구조를형성 - surface-initiated depolarization signal to provide for a uniform contraction 표면으로부터시작된탈분극신호를안쪽에있는근원섬유에게전달 ( 그래서근원섬유의위치와관계없이수축이동시에일어남 ) - Originated at the level of each A-I junctions 각각의 A-I연접에서비롯됨 Close contact with the paired terminal cisternae at the A-I junctions
A-I연접의종말수조에인접해있음 Triad formation with sarcoplasmic reticulum at A-I junctions (Fig.) A-I 연접에서근형질내세망과함께삼조체를구성 - The junctional complex between the membrane of the T-tubule and the membrane of each terminal cisterna 가로소관의막과각각의종말수조의막사이에연접복합체가존재 A low resistance junction similar to a gap junction 교통반처럼저항이낮은연접이다 # Arrangement of the sarcoplasmic reticulum and T-system in cardiac myofibres 심근의근원세포내에서의근형질내소포체과가로소관의배열 - Sarcoplasmic reticulum 근소포체 No formation of terminal cisternae 종말수조와같은구조없음 Contact with T-tubules at the individual point 가로소관- 세포와바로인접 Resultant diad 관이두개만보임 - T-tubules 가로소관 Much larger in diameter 직경이훨씬큼 Arising at the level of Z-disk Z선단면에서보임 # Arrangement of those in the smooth muscle fibres 평활근내에서의근형질내세망과가로소관의배열 - Lack of T-tubules 가로소관없음 - Sparse, unorganized sarcoplasmic reticulum 잘없으며, 구조가
잘갖춰지지않은근형질내세망 - Ends of the sarcoplasmic reticulum 근형질내소포체끝에근형질막과결합 Coupling with the sarcolemma Other cellular organelles 다른세포소기관들 - Mitochondria - Congregation in higher concentration around nucleus, along the sarcolemma, and around motor-end unit, ie., the sarcoplasmic area rich in sarcoplasm 핵과근형질막, 운동신경의말단주변에미토콘드리아이밀집 - Ribosomes - Scattered around nuclei and myofibrils 핵과근원섬유주변에흩어져있음 - Formation of myofilaments at the margins of myofibrils 근원섬유말단에서근세사형태로존재 - A Golgi complex and centrioles 골지체와중심소체 - Consistently around the nucleus in smooth myofibres 평활근원섬유의핵주변에존재 - Rarely seen in other muscle types 다른근육에서는찾아보기힘듬 Surface of myofibres and the sarcoskeleton 근원섬유와근골격의표면 - Reinforced externally by a glycoprotein coat 당단백질로코팅된표면 Basal or external lamina 기저와표면만에존재 and by reticular fibres 세망섬유
Sarcolemma 근형질막 - An extensive sarcoskeletal network 근골격구조 Intermediate filaments (10 nm) 중간세사로구성 Several different proteins 몇가지다른종류의단백질로구성 Sarcoplasm/ Sarcolemma 근세포체 / 근세포막 Cardiac and skeletal myofibres 심근원섬유과골격근원섬유 A network of transverse and longitudinal filamentous bridges Within and between the myfibrils 근원섬유내와사이에가로소관과가로세사로구성된교량존재 a. Transverse filaments (containing desmin) desmin을포함한가로세사들 Connection of adjacent myofibrils at the level of each Z-line 각 Z선에있는연접근원섬유들을연결 b. Other filaments (containing vinculin) vinculin을포함한다른세사들 Sarcoskeletal-to-sarcolemmal connections at the level of each I-band 각 I띠에서근골격과근형질막을연결 Vinculin along with an actinin (A Z-line protein) Vinculin 과 actinin (actin 구성하는단백질 )
A connecting intermediate filament at the myotendinous junctions of skeletal myofibres and at the fascia adherens junctions of intercalated disk in cardiac myofibres 골격의근원섬유의근육건연접과심근원섬유의조정판의부착연접에서연결하는기능을가진중간세사 - Function of intermediate filaments 중간세사의기능 - Transmission of the serial and parallel forces to adjacent connective tissue and other myofibres 지속적이고같은방향의힘을연접결합조직과다른근원섬유에게전달 - Intermediate filaments in the smooth myofibres 평활근원섬유에서의중간세사 Connection of actin myofilaments to electron-dense-bodies (Z-line equivalent) Transmission of contractile forces to the sarcolemma 액틴근세사와전자밀집체 (Z선) 을연결하여근형질막에수축력을전달. Again connection to the intercellular reticuloelastic net via the basal lamina 기저막을경유하여세포내 elastic세망에연결. - Intercalated disks in cardiac myofibres 심근원섬유에서의사이원반 ( 심근에서만발견되는독특한구조 Between adjacent myofibres 연접근원섬유사이에존재 Multiple junctions 다양한연접
a. Fascia adherens junctions (or Zonula adherens junction) 부착띠, 부착판연접 - The sarcoplasmic area associated with actin filaments 액틴세사주변의근형질 - Transverse orientation at Z-discs Z판의가로방향 - Transmission of contractile force 수축력전달 b. Desmosome (Macula adherens) 부착반 - The sarcoplasmic areas not associated with myofibrils 근원섬유가없는근형질에존재 - Also transverse orientation 가로방향 c. Gap junctions 교통판 - Parallel orientation/ 2 gap junctions on either side of the fascia adherens junction 부착막연접쪽두개의교통반은평행방향 - Ionically coupling the adjacent myofibres 이온으로연결된연접근섬유 Propagation of depolarization 탈분극의확대 Low resistance junctions 저항이낮은연접 - Gap junctions in smooth and skeletal myofibres 평활근원섬유와골격근원섬유의교통반 - Also between most smooth myofibres 주로평활근원섬유사이에존재 - No direct contacts with each other in skeletal myofibres 골격근원섬유들사이에직접적인연결되어있지않아서 No initiation of excitation in adjacent skeletal myofibres 골격근원섬유의연접에서흥분이전달되지않음 - Sarcolemma of myofibres 근원섬유의근형질막
- Vesicles or cavealae - Invaginations 합입 (Simple or bizzare) Branching, tubular networks or cloverleaf arrangements 수지상, 관으로되어있는체제나글로버모양의배열 - Simple vesicles 단일소포 Endo- and exocytotic vesicles 내포와외포 Complex vesicles 복합소포 Related to T-tubules 가로소관과관련 A band Dark interval including H band H 밴드를포함한어두운구역 A part including myosin filaments H band - Pure myosin filaments 순수한미오신섬유 No thin filament involved 얇은섬유를포함하지않음 b. Lines M line - Middle portion of myosin filament/ M-line protein (creatine kinase, ATP supply) 미오신의중앙부분 / M -line 부위 Z line or disk - Attaching point of actin filament 액틴섬유의붙는장소 Middle of I band - Zwischenscheiben Dense protein (Alpha-actinin, anchor the actin
filaments to this region) 밀집한단백질 (ɑ-액티닌, 액틴섬유를이구역에붙인다.) Pseudo H zone 가 ( 모조 ) H존 Within the H band, on either sides of the M line H 결합안에 M 라인이없는부위.( 양옆의부위 ) A thin, electron-lucent region 얇고, 전자밀도가낮은지역 Devoid of the myosin cross-bridge 측쇄사슬미오신이거의없다.(C protein)