Pituitary Gland

Question 1

Describe the anatomy of the pituitary gland

Answer 1

This is a bean sized organ connected superiorly to the hypothalamus by the infundibulum, it sits in the sella turcica of the sphenoid bone and is divided into the anterior and posterior pituitary.

Question 2

What is the anterior pituitary derived from?

Answer 2

It has epithelial origin from embryonic origin, arising form the tissue that formed the roof of the mouth

Question 3

What is the posterior pituitary formed from?

Answer 3

It is an extension of the neural tissue of the hypothalamus

Question 4

What 2 hormones does the posterior pituitary secrete?

Answer 4

Vasopressin(ADH) and oxytocin

Question 5

What do each of the hormones secreted by the posterior pituitary target and what is their main function?

Answer 5

ADH - kidneys, regulates water balance

Oxytocin - uterus and mammary glands, milk election and uterine contraction

Question 6

Name the 6 hormones released by the anterior pituitary

Answer 6

Luteinising hormone 
Adrenocorticotrophic hormone
Follicle stimulating hormone 
Thyroid stimulating hormone
Growth hormone
Prolactin

Question 7

What is the target of all anterior pituitary hormones with the exception of prolactin?

Answer 7

Another endocrine gland or cell

Question 8

What is a trophic hormone?

Answer 8

A hormone that affects the secretion of another hormone

Question 9

What type of hormones are released form the hypothalamus?

Answer 9

Neurohormones

Question 10

What type of hormones are released from the anterior pituitary?

Answer 10

Classic endocrine hormones

Question 11

What type of hormones are released form the posterior pituitary?

Answer 11

Neurohormones

Question 12

What system connects the hypothalamus ad the anterior pituitary?

Answer 12

The hypothalamo-hypophyseal portal system

Question 13

What is the advantage of this system in terms of hormone release?

Answer 13

This system does not connect to the general circulation and thus does not dilute the hormone released from the hypothalamus, this reduces the concentrations of hormone required to induce a response.

Question 14

Where are hormones released from the hypothalamus?

Answer 14

Median eminence

Question 15

Name the 5 trophic hormones released form the hypothalamus to the anterior pituitary

Answer 15

Thyrotrophin releasing hormone(TRH)
Corticotrophin releasing hormone(CRH)
Growth hormone releasing hormone (GHRH)
Gonadotrophin releasing hormone (GnRH)
Prolactin releasing hormone (PRH)

Question 16

What is the instigator of negative feedback in the Hypothalamic-Pituitary Pathway?

Answer 16

The hormones produced themselves

Question 17

Define the long feedback loop

Answer 17

When the final hormone in the pathway feedback to suppress its trophic hormones

Question 18

Describe the short feedback loop

Answer 18

Where the pituitary hormones feedback to suppress the release of the trophic hormones form the hypothalamus.

Question 19

What are 1st order endocrine disorders?

Answer 19

Defect is within the cells that secrete the hormone

Question 20

What are 2nd order endocrine disorders?

Answer 20

There is too little or too much trophic hormone released from the pituitary

Question 21

What are 3rd order endocrine disorders?

Answer 21

Disorders of the hypothalamus