5.3. neuroendocrine system

GH levels are controlled by 2 hormones

• Stimulated by GHRH

• Inhibited by somatostatin (SS)

Functions of GH happens through

• insulin-like growth factors (IGFs) that are produced in the liver in response to GH

GH levels has an effect on

• Growth

• Metabolism

Metabolism

• Increases protein synthesis rate (especially in skeletal muscle)

• Promotes the degradation of lipids (lipolysis).

• Increases blood glucose

Growth

• Bone, cartilage & soft tissue elongation

• Helps maintain muscle mass, bones, & tissue repair in adults.

Stress hormones

• inhibit GH secretion.

Exercise

•  Exercise stimulates GH secretion.

Acromegaly

• Excessive growth during development

• Excessive growth of bones in adulthood (hands and face)

GH DEFICIENCY

• Hypopituitary dwarfism

• Impaired cartilage development & shorter bones

The adrenal glands are made up of two distinct tissues:

• MEDULLA

• CORTEX
  

CORTEX

Secretes steroid hormones (all derived from cholesterol).

The adrenal cortex is the primary source of glucocorticoids: Cortisol

It also produces mineralocorticoids (for blood pressure and electrolyte balance) and

weak sex hormone precursors (androgens).

MEDULLA

Connected with the Sympathetic Nervous System.

Produces catecholamines:

Adrenaline