內分泌系統-3.

Presentation on theme: "內分泌系統-3."— Presentation transcript:

1 內分泌系統-3

2 激素的作用機制 Mechanisms of Hormone Action
Hormones of same chemical class have similar mechanisms of action. Location of cellular receptor proteins. Target cell must have specific receptors for that hormone (specificity). Hormones bind to receptors with high bond strength (affinity). Low capacity of receptors (saturation).

3 摘自 新編生理學 永大出版社

4 與細胞核內受器蛋白結合的激素 Hormones That Bind to Nuclear Receptor Proteins

5 Receptor of steroid hormone

6 Mechanisms of thyroid hormone action

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8 利用第二傳訊者的激素 Hormones That Use Second Messengers
Cannot pass through plasma membrane. Catecholamines, polypeptides, and glycoproteins bind to receptor proteins on the target cell membrane. Actions are mediated by 2nd messengers (signal-transduction mechanisms). Extracellular hormones are transuded into intracellular second messengers.

9 利用第二傳訊者的激素 Hormones That Use Second Messengers
3 classes of 2nd messenger systems: Adenylate cyclase (腺苷酸環化酶)- cAMP, cGMP. Phospholipase C (磷脂酶)- IP3, DAG. Tyrosine kinase (酪胺酸激酶).

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12 利用第二傳訊者的激素 Hormones That Use Second Messengers
3 classes of 2nd messenger systems: Adenylate cyclase (腺苷酸環化酶)- cAMP, cGMP. Phospholipase C (磷脂酶)- IP3, DAG. Tyrosine kinase (酪胺酸激酶).

13 DAG

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15 (DAG)

16 利用第二傳訊者的激素 Hormones That Use Second Messengers
3 classes of 2nd messenger systems: Adenylate cyclase (腺苷酸環化酶)- cAMP, cGMP. Phospholipase C (磷脂酶)- IP3, DAG. Tyrosine kinase (酪胺酸激酶).

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