THE ENDOCRINE SYSTEM For Wed. Oct. 11 Please print out this powerpoint and fill in the portions with a red * in front of them

The Endocrine System Pituitary Gland

I. The Endocrine System: An Overview *Overall Function = B. *Uses Chemicals = C. *Control and Integration of what: *Endocrine Glands E. *Neuroendocrine Gland = *Chemicals similar to Hormones: *Autocrines: *Paracrines:

II. Hormones Charateristics A. The Chemistry of Hormones 1. *Types *Amino acid based: *Water Solubility? *Examples *Steroids: - *Water Solubility? - *Examples

B. Mechanisms of Hormone Action Overview a) *Target cells = ? b) *Number Organ systems affected? Typical Affects: Text Page 597 *Receptor = *Receptor Location: Lipid Hormones Non=Lipid Hormones

B. Mechanisms of Hormone Activity … Two Main Mechanisms 2. Plasma Membrane Receptors: a. *Type Chemical: - except: *Second Messenger (indirect): c. The Cyclic AMP Signaling Mechanism Hormone binds to: Second messenger produced: Hormones that act via cAMP: Epinephrine ACTH FSH LH Glucagon PTH TSH Calcitonin hormone receptor 6

Hormone (1st messenger) binds receptor. 1. Plasma Membrane Receptors and Second-Messenger Systems … a. The Cyclic AMP Signaling Mechanism … Hormone (1st messenger) binds receptor. 1 Extracellular fluid Receptor Cytoplasm Figure 16.2, step 1

Hormone (1st messenger) binds receptor. Extracellular fluid Adenylate cyclase Receptor cAMP (2nd messenger) is produced. 4 GDP Cytoplasm Figure 16.2, step 4

Which triggers responses 1 Hormone (1st messenger) binds receptor. Extracellular fluid Adenylate cyclase 5 cAMP activates protein kinases. G protein (GS) Receptor cAMP (2nd messenger)is produced. 4 GDP Inactive protein kinase Active protein kinase Which triggers responses Cytoplasm Figure 16.2, step 5

B. Mechanisms of Hormone Activity … Two Main Mechanisms 3. Intracellular Receptors: a. *Type Chemical: Intracellular Receptors c. Intracellular Receptors and Direct Gene Activation Entrance of Hormone: Receptor binds to: Activated Gene: Protein produced changes d. *Examples of Hormones lipid hormone receptor 10

B. Mechanisms of Hormone Activity … : Lipid Hormone Receptor 1

Receptor-hormone enters nucleus. Steroid hormone Plasma membrane Extracellular fluid 1 Cytoplasm Receptor protein Receptor- hormone complex 2 Receptor-hormone enters nucleus. Nucleus Figure 16.3, step 2

binds to a specific DNA sequence). Steroid hormone Plasma membrane Extracellular fluid Cytoplasm Receptor protein Receptor- hormone complex Hormone response elements Nucleus 3 binds to a specific DNA sequence). DNA Figure 16.3, step 3

transcription. Steroid hormone Plasma membrane Extracellular fluid 1 Cytoplasm Receptor protein Receptor- hormone complex 2 Hormone response elements Nucleus 3 DNA transcription. 4 mRNA Figure 16.3, step 4

– an enzyme, structural protein, a secretion, etc… Steroid hormone Plasma membrane Extracellular fluid 1 Cytoplasm Receptor protein Receptor- hormone complex 2 Hormone response elements Nucleus 3 DNA 4 mRNA protein synthesis.  new protein – an enzyme, structural protein, a secretion, etc… 5 New protein Figure 16.3, step 5

II. Hormone Characteristics … C. Interactiion of Hormones at Target Cells Permissiveness: Example: Synergism: Antagonism:

D. Control of Hormone Release-- Homeostasis 1. Control by Negative Feedback Loops A Stimulus: Control Center: Effector: Results: Feedback to Endocrine Gland  Calcium homeostasis of blood 9–11 mg/100 ml Rising blood Ca2+ levels Thyroid gland releases calcitonin Osteoclasts degrade bone matrix and release Ca2+ into blood PTH Calcitonin Calcitonin stimulates calcium salt deposit in bone Parathyroid glands release parathyroid hormone (PTH) Thyroid gland Parathyroid glands Falling blood Ca2+ levels Imbalance

C. Control of Hormone Release … 2. Endocrine Gland Stimuli–3 a. Humoral Stimuli (simplest) Humoral = Ends when: Hormones: Parathyroid hormone Calcitonin Insulin

2. Endocrine Gland Stimuli … b. Neural Stimuli = Examples = Sympathetic Nervous System to Adrenal Gland interaction c. Hormonal Stimuli (most complex) i) Hormones: Example: Hypothalamus and Pituitary Gland Interactions

1. Endocrine Gland Stimuli … iii EXAMPLE:Hypothalamic and Pituitary Gland interactions - Uses Negative Feedback Hypothalamus Releasing and Inhibiting Hormones: Function: Stimulate or Inhibit the release of the Anterior Pituitary Hormones Anterior Pituitary Hormones: Function: Produce Stimulating Hormones that stimulate other endocrine glands Final Hormone of feedback loop: it negatively feeds back to stop the Hypothalamus and Pituitary from releasing their hormones

Major Endocrine Glands and Hormones Suggestion: Make notecards with Endocrine Gland Images – include targets, affects, and regulation (control loops)

Major Endocrine Glands and Hormones Table 9.1 (1 of 4) 22

Major Endocrine Glands and Hormones Table 9.1 (3 of 4) 23

Major Endocrine Glands and Hormones Table 9.1 (4 of 4) 24

MAJOR ENDOCRINE GLANDS III. Pituitary Gland and Hypothalamus A MAJOR ENDOCRINE GLANDS III. Pituitary Gland and Hypothalamus A. HYPOTHALAMUS Hormones produced in Hypo, but released by Ant Pit. 1. OVERVIEW: two types of H. a) *Hormones that go to the Anterior Pituitary via blood are called what? Affect Pituitary’s release of its own hormones Hormones that go to the Posterior Pituitary via axons Travel to Post Pituitary Hormones are released from the Posterior Pituitary The go to a target organ and have some effect. Releasing & Inhibiting Hormones Anterior Pituitary Posterior Pituitary

A. HYPOTHALAMUS … Hypo. Hormones that go to the Posterior Pituitary *Posterior Pituitary Tissue: *Hormones are made in the hypothalamus, but move to where? *Using what structures? *Which are located where? *In post Pit: hormones are stored in what? *and then released how? Hormones are: Oxytocin and ADH 1

Relationships of Posterior Pituitary & HYPO. Hypothalamas synthesizes oxytocin and ADH. 1 Paraventricular nucleus Hypothalamus Supraoptic nucleus Oxytocin and ADH transported along hypothalamic-hypophyseal tract to pituitary. 2 Optic chiasma Infundibulum (connecting stalk) Inferior hypophyseal artery Hypothalamic- hypophyseal tract Oxytocin and ADH stored in axon terminals in posterior pituitary. 3 Axon terminals Oxytocin and ADH released into blood when neurons fire. 4 Posterior lobe of pituitary Oxytocin ADH (a) Relationship between the posterior pituitary and the hypothalamus

to the Anterior Pituitary *Are what type? A. Hypothalamus … 3. Hormones that go to the Anterior Pituitary *Are what type? General Naming Rule: Name of Anterior Pituitary Hormone followed by Releasing or Inhibiting Hormone *Produced & Released in: *Hormones carried in what? Via special blood vessels = Hypophyseal Portal System which: *Then: Anterior Pituitary responds by: Releasing & Inhibiting Hormones 1st Capillary Plexus Hypophseal Portal Veins 2nd Capillary Plexus