5_Endocrine System II

Page 1: Quiz Instructions

  • Complete Quiz 2 on iCollege.

    • Use Lockdown Browser within the first 15 minutes of class.

    • Note: Access to Quiz will disappear after 15 minutes.

  • Take time to review Quiz 1

    • Focus on answers you chose in Lockdown Browser.

Page 2: Endocrine System Overview

  • Title: Introduction to the Endocrine System

  • Visual: A cartoon depiction expressing concern for hormone levels.

Page 3: Commonality Among Individuals

  • Question: What do these people have in common?

  • Potential exploration of individuals with hormonal imbalances or notable endocrine disorders.

Page 4: Historical Figures and Hormonal Disorders

  • Charles Byrne (1761-1783)

    • Height: Estimated 7 ft 7 in

    • Diagnosed with Acromegaly (excess growth hormone).

  • Goliath (Biblical Figure)

    • Height: Over 9 ft?

  • Discussion: Effects of unbalanced hormones on growth and height.

Page 5: Major Endocrine Structures

  • Hypothalamus

    • Regulates control of hormone secretions.

  • Pineal Gland

    • Regulation of body rhythms and reproductive maturation.

  • Pituitary Gland

    • Anterior pituitary: Hormone secretion for growth, metabolism.

    • Posterior pituitary: Additional functions.

  • Kidneys

    • Regulate water and salt balance.

  • Thyroid

    • Growth and metabolic rate regulation.

  • Adrenal Glands

    • Inner medulla and outer cortex involved in stress response, metabolism.

  • Pancreas

    • Regulates sugar metabolism.

  • Gonads

    • Maintenance of reproductive organs.

Page 6: Protein Hormones in Hypothalamus

  • Key Hormones:

    • Thyrotropin-releasing hormone (TRH): Stimulates TSH production.

    • Growth Hormone-releasing hormone (GHRH): Stimulates GH production.

    • Gonadotropin-releasing hormone (GnRH): Stimulates gonadotropins.

    • Corticotropin-releasing hormone (CRH): Stimulates ACTH release.

    • Growth hormone-inhibiting hormone (GHIH): Inhibits GH.

    • Gonadotropin-inhibitory hormone (GnIH): Inhibits gonadotropins.

Page 7: Other Hormones of Hypothalamus

  • Vasopressin (Antidiuretic hormone):

    • Affects water balance.

    • Diabetes insipidus is related to dysregulation.

  • Oxytocin:

    • Triggers uterine contractions and milk letdown.

    • Associated with social-related behaviors.

Page 8: Pituitary Gland Structure

  • Comprised of two distinct glands:

    • Anterior Pituitary (Adenohypophysis)

    • Posterior Pituitary (Neurohypophysis)

Page 9: Anterior Pituitary Details

  • Derived from the roof of the mouth.

  • Hormones released from the hypothalamus are transported to this gland to regulate hormone release.

Page 10: Hormonal Interactions in Anterior Pituitary

  • Neuroendocrine Cells release:

    • CRH → ACTH → Adrenal Cortex (Stress response).

    • TRH → TSH → Thyroid (Metabolic regulation).

    • GnRH → FSH/LH → Gonads (Reproductive function).

Page 11: Posterior Pituitary Function

  • Forms from an outpouching of the brain.

  • Hormones are secreted directly from hypothalamic neurons into the bloodstream.

Page 12: Thyroid Gland Overview

  • Thyroid hormones developed from tyrosine.

    • Main hormones:

      • Thyroxine (T4)

      • Triiodothyronine (T3)

    • Can cause goiter if levels are imbalanced.

Page 13: Adrenal Glands

  • Comprised of two segments:

    • Adrenal Cortex: Produces steroid hormones (corticoids, androgens).

    • Adrenal Medulla: Produces amine hormones (norepinephrine, epinephrine).

    • Responsible for the body's stress response.

Page 14: Cushing's Syndrome Overview

  • Description of connection with endocrine disorders.

  • Visual representation of affected individuals.

Page 15: Testes Function

  • Steroid Hormones: Produced by Leydig cells (androgens).

  • Protein Hormones: Produced by Sertoli cells (Mullerian inhibitory hormone during development).

Page 16: Ovaries and Related Structures

  • Hormone Production:

    • Steroid Hormones: Estrogens (from theca cells) and Progesterone (from corpus luteum).

  • Anatomy of ovaries and their connection to reproduction.

Page 17: Pancreas Hormonal Functions

  • Key protein hormones include:

    • Insulin (β cells): Converts glucose to glycogen.

    • Glucagon (α cells): Converts glycogen back to glucose.

    • Somatostatin (δ cells): Regulates insulin and glucagon levels.

Page 18: Pineal Gland Overview

  • Produces Melatonin (an amine hormone).

    • Important for regulating biological rhythms associated with light exposure.

Page 19: Stomach Hormones

  • Ghrelin: A protein hormone that stimulates appetite.

  • Leptin: A protein hormone from fat cells that induces energy expenditure and inhibits appetite.

Page 20: Leptin and Obesity

  • Visual comparison of a morbidly obese child before and after treatment with leptin.

    • Implications for weight management and metabolic health.

Page 21: Hormonal Regulation

  • Positive Feedback Loop:

    • Exemplified from day 12-14 of the menstrual cycle with GnRH activation.

  • Negative Feedback Loop:

    • Predominant throughout the cycle involving FSH, LH, estrogen, and progesterone.

Page 22: Hypothalamo-Pituitary Adrenal (HPA) Axis Regulation

  • Overview of CORT in humans (cortisol) and in rodents (corticosterone).

  • Key point: Negative feedback plays a significant role in regulation.

Page 23: Hormonal Pathways & Enzymes

  • Detailed biochemical pathways related to cholesterol and its derivatives (progestagens, mineralocorticoids, glucocorticoids).

Page 24: Homework Assignment

  • Re-read Nelson (2010) for deeper understanding of the Endocrine System.

  • Important for upcoming Assignment 4 in-class on Monday.