The Endocrine System (1) Copy.pdf

The Endocrine System Chemical Signals  Pheromones  Kairomones  Hormones Glands  Endocrine  Exocrine Exocrine Endocrinology  Target cells  Receptors Regulation  Down regulation  Up regulation Hormone action  Endocrines  Paracrines  Autocrines Classes of hormone...

The Endocrine System Chemical Signals  Pheromones  Kairomones  Hormones Glands  Endocrine  Exocrine Exocrine Endocrinology  Target cells  Receptors Regulation  Down regulation  Up regulation Hormone action  Endocrines  Paracrines  Autocrines Classes of hormones  Steroids Classes of hormones  Steroids  Biogenic Amines Classes of hormones  Steroids  Biogenic Amines  Peptides and Proteins  Eicosanoids  Arachidonic acid Concept Check  Where in the cell are steroid hormones synthesized?  Steroid hormones are synthesized on the membrane of the smooth ER.  Where are peptide hormones synthesized?  Peptide hormones are synthesized on rough ER.  Which of these 2 types of hormone could be stored in vesicles and released by exocytosis? Explain.  Peptide hormones can be stored in vesicles and released by exocytosis. Mechanisms of Hormone Action  Lipid Soluble Hormones Mechanisms of Hormone Action  Water Soluble Hormones Hormonal Interactions  Permissive Effect  Synergistic Effect  Antagonistic Effect Hormonal Interactions  Permissive Effect  One hormone must be present for the other to function  Up-regulation of one hormone’s receptors by another hormone  The facilitation of the action of one hormone by another Hormonal Interactions  Synergistic Effect  Two hormones acting together for a greater effect  Effects may be additive  Complementary – each hormone stimulates a different step in the process. Ex: FSH and testosterone Hormonal Interactions  Antagonistic Effect  Two hormones with opposite effects  Ex: insulin promotes glycogen formation. Glucagon stimulates glycogen breakdown.