Introduction the Endocrine System Chapter 7

What is a endocrine?

We divide endocrines into 3 groups Steroid hormones Peptide hormones Amine hormones

Steroids

The Adrenal Gland: one source of steroids

All contain the cholesterol backbone

Notice how similar estrogen is to cortisol

Amines

Amines as hormones: modified amino acids

Pre-pro-hormone to Active hormone

Endocrine System: Wow! →Pituitary →Hypothalamus Pineal gland Thyroid Parathyroid Thymus Heart liver Stomach and intestine Pancreas Adrenal gland Kidney Testes Ovaries Adipose placenta

Hypothalamus and pituitary

The protein hormones of these glands

Control of Hormone Release

1. Hypothalamic Control of Anterior Pituitary

1a. Most endocrines are controlled by Trophic factors

1b. A few endocrines are controlled by inhibition Somatostatin PIF

2. Hormone Secretions can be controlled by Positive feedback Negative feedback

Negative Feedback Control

Positive Feedback Control

Feedback can be: Short Loop Feedback Long Loop Feedback

Short Loop Long Loop Feedback

Interactive affect of multiple hormones Synergism Permissiveness Antagonism

Pathologies Diabetes MellitusType I Diabetes Inspidius Hyperthyroidism Graves Disease Hypothyroidism Cushings Disease: secondary hypersecretion Addison’s Disease: primary hyposecretion

Pancreas and Insulin

Diabetes Mellitus Type I Insulin deficiency Type II Non-responsive to insulin

CUSHING DISEASE

Cushing Disease Excess gluconeogenesis: hyperglycemia Muscle breakdown Lipolysis Paradox: central weight gain

Cushing and its treatment

Addison’s Disease

Goiter: Enlarged Thyroid Gland

Exophthalmus

Primary hypersecretion at “final” site

Secondary Hypersecretion: at pituitary level

Secondary Hypersecretion at hypothalamic level