Cardiac Muscle - anatomical a me ka physiological hiʻona

Ka naau Muscle eaaaony e pōʻino oihana o nā mea a pau nā'aʻaʻa, aeee a me nā loko. Amo ana o 'ona i loko o ke kino ua lawe mai ma mau koko holo; Ua hoʻi i nā kōkua ma muli o a homeostasis.

Ka 'ole o ka naʻau Muscle

Ka naau ua poe e mau halves - hema a me ka pono, kela mea keia mea o ka i ninoieo o ka atria a me ventricles. Ka hema hapalua o ka naau EII ni ka arterial koko, a me ka pono - venous. No laila, i ka naau Muscle o ka hapa hema mea nui ka pūhaka o ka'ākau. Nāʻiʻo o ka atria a me ventricles i kaawale e fibrous apo i i atrioventricular kiwikā: elua-pelu ana (hema hapalua o ka naʻau) a me ka tricuspid (pono hapalua o ka naau). Mau kiwikā iloko o cardiac contraction pale aku i ka hoi ana mai o ke koko i loko o ka atria. Ma ka OAAIeOO o ka aorta a me ka pulmonary artery e kau fortnightly kiwikā, i pale aku i ka hoi ana o ke koko a hiki i ka ventricles iloko o diastole huina naau.

Cardiac Muscle no i striated Muscle'aʻaʻa. No laila, i kēia Muscle i ka ia waiwai e like me ia o skeletal Muscle. Muscle puluniu ninoieo o myofibrillar a me ka sarcoplasmic sarcolemma.

Mahalo i ka naau, e haawi aku i ke koko ma na ipu koko. Ke rhythmic contraction o na nāʻiʻo o ka atria, a me nā ventricles (systole) koho 'ē aʻe me kona hoʻomaha (diastole). Sequential loli o ka systole a me diastole o ka pōʻaiapuni o ka naau. Ka naau Muscle ua hana rhythmically, i hoakakaia ma ka'ōnaehana, e mālama nei i manaʻo pīhoihoi i loko o nā wahi likeʻole o ka naʻau

Ke physiological waiwai o ka naau Muscle

Ke excitability o ka myocardium - o kona hiki e pane koke i ka uila, me mechanical, thermal a me ka Nine Inch stimuli. Ke excitation a me contraction o ka naau Muscle ia lŘlŘ ka wā o ka stimulus kīnā i ka paepae max. Emi loa paepae mea i pono, a mai e hoʻololi i ka suprathreshold ikaika o myocardial contraction.

Excitation o ka Muscle'aʻaʻa o ka naau pu ma ke ano o ka hanaʻia. He hoopokole a ua hooloihiia ma ka kaoo naau kōmi deceleration.

Pīhoihoi ka naʻau Muscle pokole haalele i kona hiki e pane i hou stimuli a me impulses e hele mai ana, mai ka kumu o ka automaticity. Keia ua kapaia ka refractory ole-excitable. Ikaika stimuli e hana ma luna o ka Muscle i loko o ke au o ka pili refractoriness e i ka halawai contraction o ka naau - ka ai-kapaia premature kui iho oe a.

Myocardial i nā hiʻona i loko o e like me ka skeletal Muscle'aʻaʻa. Ke excitation a contraction ma cardiac Muscle hope hou ma mua o skeletal. Ma cardiac Muscle aerobic keʻano o ka hanaʻana lanakila resynthesis waiwai i huiʻia. Ma diastole, he mea ka 'akomi loli o kaʻili lahilahi Loaʻaʻia i loko o kekahi mau keena ma ka wahi likeʻole o ka paena. Nolaila i ka pīhoihoi hohola na nāʻiʻo o ka atria, a hiki i ka atrioventricular wahi, a ua manaoia i ka piko o ka automaticity II mea. Inā aku sinoatrial wahi (ligated, ka huʻihuʻiʻana, hoomake iho no hoi), a laila, ma hope o ke ana o nā ventricles hoʻomaka i ka aelike hou pohihihi pāpana ma lalo o ka aoao o impulses i kupu mai ma ka atrioventricular wahi.

Conduction o excitation i loko o nā wahi likeʻole o ka kaiʻewaʻewa naau. Mākou e'ōlelo ana ma ka mehana-koko holoholona ana o ka excitation o atrial Muscle olona, i kahi o 1.0 m / s; ka lawelawe ventricular'ōnaehana i ka 4.2 m / s; i loko o ka ventricular myocardium i 0,9 m / s.

A ano hiʻona o ka excitation o ka naau Muscle mea i ka hanaʻia, kena ae la i kekahi hapa o ka Muscle'aʻaʻa, hohola iho la i nā hoʻopunipuni.