Pit gland and disorders ADD

Question 1

How do pituitary hormones maintain their target hormones?

Answer 1

They not only cause release from target organs of hormones, but they also maintain them. – cause the target glands to continue to grow, and when you don’t have pit hormones, those target glands shrink.

Question 2

Endocrine system is organided into 3 layers. Describe.

Answer 2

1. Primary – end organ
2. Secondary - pituitary
3. Tertiary - hypothalamus
   • So, integration and translation of signals in the hypothalamus.
   • Amplification of signal in the pituitary
   • And the principle of negative feedback to allow dynamism.

• End organ hormone production sense your endocrine status, - into being hypofunctioning, hyperfunctioning or eufunctioning (normal).
• Endocrine tests always start with the end organ first.

Question 3

Advantage of the hypothalamus releasing hormones into the hypophyseal circulation, rather than the general circulation?

Answer 3

Blood vessel only contains 2.3ml of blood. -> So, tiny amounts of hormones in that blood would have a high concentration.

Question 4

What is IGF-1 and what is it’s role?

Answer 4

IGF-1 = Insulin-like growth factor 1.
IGF-1 stimulates the chondrocytes in the long bone, to cause linear growth of the bone.
Supplies negative feedback - as well as a small amount of GH.