生理学5.1.1.22 lecture30-内分泌E1

The “classic members” are useful for learning
They are important They provide order to learning They introduce key concepts (hormonal axis)
Remember that it is an artificial “system”
Epsilon Cells – Ghrelin? (<0.5%)
A minority of the pancreas is an secretory endocrine gland
These collections of endocrine cells are called the Islets of Langerhans
Endocrine Pancreas
Endocrine Pancቤተ መጻሕፍቲ ባይዱeas
Endocrine System
The classic members:
Hypothalamus and Pituitary Gland Pineal Gland Endocrine Pancreas Thyroid Parathyroids Adrenals Gonads
Endocrine System
Key Concept Five:
What other hormones act on similar targets with similar effects?
Redundancy Multiplicity
Endocrine Key Concepts
Key Concept Six:
How do these different hormones affect body metabolism?
Single or Multiple Target Cells Single or Multiple Receptors
Endocrine Key Concepts
Key Concept Two:
What is the site of hormone release and its pathway to target tissue?
Free Body Diagram
Endocrine Key Concepts
It’s important to keep these ideas in mind when thinking about the endocrine system
Endocrine Pancreas
The majority of the pancreas is a secretory exocrine gland
Focal: Hypothalamus Pituitary Global: Thyroid Hormone Body
Endocrine Key Concepts
Key Concept Three:
What effects do secretion, excretion, and degradation have on hormone levels?
Endocrine
Jim Pierce Bi 145b Lecture 10
Endocrine System
The endocrine system is concerned with “internal secretions”
“endo-” “-crine”
What makes up the endocrine system? (Actually… quite a difficult question)
Endocrine System
Distance of Hormone Action
Autocrine Paracrine Endocrine
We typically leave out “local” hormones The grey area occurs because no hormone is purely local.
Islets contain:
Alpha Cells Beta Cells Delta Cells PP Cells
- Glucagon - Insulin - Somatostatin - Pancreatic Polypeptide
(15-20%) (65-80%) (3-10%) (< 1%)
Steady State Disequilibrium
Endocrine Key Concepts
Key Concept Four:
What computational structures exist to control and regulate hormonal levels?
AXIS Other Control Structures
Organ Hormones (GI, Cardiac, Pulmonary) Cytokines (Immune Hormones) Orphan Endocrine Cells
Endocrine Key Concepts
Key Concept One:
For each hormone, what is the target cell and its receptor?
Endocrine Key Concepts
Axis:
A linear control structure consisting of a series of cells each secreting one hormone to stimulate the subsequent cell.
Endocrine Key Concepts
Examples of Axes:
Hypothalamic – Pituitary – Adrenal Hypothalamic – Pituitary – Thyroid Hypothalamic – Fat axis Renin – Angiotensin – Aldosterone
Endocrine Key Concepts