细胞、激素（Cell and hormone）.docVIP

细胞、激素（Cell and hormone） Cell and hormone adrenaline Epinephrine is a hormone and neurotransmitter. The Latin prefix ad Renes means on the kidney, liver.. Sometimes epinephrine can be abbreviated as epi. Epinephrine (adrenaline, epinephrine, AD) is the main hormone of the adrenal medulla, its biosynthesis is mainly in the medulla chromaffin cells first form noradrenaline, then the phenylethylamine -N- methyltransferase (phenylethanolamine N-methyl, transferase, PNMT) the role of the methylation of norepinephrine adrenaline form. The general effect of epinephrine increases the contractility of the heart, the dilatation of the heart, liver, and muscles, and the narrowing of the blood vessels in the skin and mucous membranes. On drugs, epinephrine is used to dilate the trachea when the heart stops and is used to stimulate the heart or asthma. Epinephrine can increase the contractility of the myocardium, increase the excitability, accelerate the conduction and increase the cardiac output. The effect of blood vessels on all parts of the body is not only different, but also different from contraction or relaxation. The blood vessels of the skin, mucous membranes and internal organs (such as the kidneys) act as contraction, and dilate the coronary arteries and skeletal muscles. Because it acts directly on the coronary vessels, causing vasodilation and improving the blood supply to the heart, it is a powerful and powerful cardiac drug. Epinephrine also relaxes bronchial smooth muscle and relieves bronchial smooth muscle spasm. Use its excitement, heart contraction, blood vessels and relaxation of bronchial smooth muscle and so on, can alleviate the heartbeat, blood pressure drops, breathing difficulties and other symptoms. Epinephrine, the old term epinephrine, is commonly used to increase the contractility of the heart, vascular dilatation of the heart, liver, and bones, and vasoconstriction of the skin and mucous membranes. On drugs, epinephrine is used to dilate the trach