Endocrine Histology

Question 1

Where is the ptuitatry located?

Answer 1

sella tercica, part of the sphenoid bone.

Question 2

Adenohypophsis part

Answer 2

made up of the pars distalis, pars intermedia, and pars tuberalis

Question 3

The posterior pituitary,

Answer 3

or pars nervosa (or infundibular process), the infundibular stem or stalk, and the median eminence.

Question 4

Rathke’s puch

Answer 4

gives rise to ant pituitary

Question 5

ant. pit acidophils

Answer 5

GH or PRL

Question 6

ant pit basophils

Answer 6

TSH, ACTH, LH and FSH

Question 7

Ant Pit chromophones

Answer 7

cells lacking granules which are thought to be in a resting state ot may have been degranulated

Question 8

vessel giving blood to median eminence

Answer 8

superior hypophyseal a. (branch of int. carotid.)

Question 9

how does blood drain from ant. and post. pit?

Answer 9

small hyophyseal veins

Question 10

Role of pars intermedia

Answer 10

poorly developed in humans, consisting of colloidal cysts. Produce MSH.

Question 11

Explain the nuclei that can be seen in the post pit.

Answer 11

pituicytes, supportive astocyte-like glial cells.

Question 12

post pit pro hormones

Answer 12

The prohormones are called vasopressin-neurophysin and oxytocin- neurophysin

Question 13

Structure of thyroid

Answer 13

The thyroid is a multi-lobed gland comprised of a series of follicles, each having a single layer of epithelial cells surrounding a central chamber referred to as the colloid

Question 14

what produces the colloid in thyroid gland?

Answer 14

The epithelial cells are producers of the colloid and ultimately the thyroid hormone group.

Question 15

Blood supply to the thyroid is

Answer 15

via the inferior thyroid artery (from the thyrocervical trunk) and the superior thyroid artery (from the external carotid artery);
drainage is from the inferior thyroid vein (to the subclavian vein) and the superior thyroid vein (to the jugular vein).

Question 16

Release of thyroglobulin

Answer 16

done by epithelial cells surrounding a central chamber referred to as the colloid. The epithelium also synthesizes and secretes the protein thyroglobulin into the interior of the follicle and takes up and digests thyroglobulin to generate the thyroid hormones.

Question 17

Calcitonin “C” cells

Answer 17

aka parafollicular cells found in thyriod producing calcitonin (hormone that decreases relase of Ca++ from bone, down regulates osteoclasts. opposite effect to parathyroid)

Question 18

3 types of cells in parathyroid

Answer 18

(1) Chief cells, produce PTH, It increases osteoclast release of calcium from bone, and increases calcium uptake in the GI tract and by the kidney, (
2) Oxyphil cells, which contain a number of mitochondria, usually stain paler but whose functional significance remains unknown, and
(3) Adipose cells

Question 19

Adrenal gland blood supply

Answer 19

Blood is delivered via the superior, middle and inferior suprarenal arteries, which branch and enter through the capsule via short cortical arteries into an outer subcapsular arterial plexus. Blood then passes via an anastomosing network of capillaries into the medullary region. Other arteries (long cortical arteries) take blood to medullary region more directly, with the blood ultimately entering a series of small capillaries/sinuosoids to the central medullary vein, which drains via the suprarenal vein.

Question 20

Layers of the adrenal cortex and corresponding hormones

Answer 20

1. Zona glomerulosa: mineralocorticoids, most notably aldosterone
2. Zona fasciculaWa: glucocorticoids such as cortisol
3. Zona reticularis: Androgens of modest potency.

Question 21

what hormones regulates the glomerulosa?

Answer 21

angiotensin system

Question 22

what hormones regulates reticularis and fasiculata?

Answer 22

ACTH

Question 23

Medulla structure

Answer 23

contains EPI & NE producing cells arranged as clusters around venous channels/sinusoids that drain toward the central medullary vein.

Question 24

Regulation of medulla

Answer 24

symp and para symp

Question 25

Parathyroid cell structure

Answer 25

Chief, or principal cells (encircled in black) are smaller and more numerous, and are arranged in cords or nodules. They secrete parathyroid hormone. Oxyphils are less numerous. They are more eosinophilic (pink) larger, and are arranged in nodules (encircled in red).

Question 26

Define urogenital ridge

Answer 26

One of the paired longitudinal ridges developing in the dorsal body wall of the embryo, formed at first by the growing mesonephros and later by the mesonephros and the gonad. Also called mesonephric fold, Wolffian ridge. The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

Question 27

Define neural crest

Answer 27

group of embryonic cells that are pinched off during the formation of the neural tube (the precursor of the spinal cord) but that do not remain as a part of the central nervous system. The cells of the neural crest migrate to numerous locations in the body and contribute to the formation of diverse structures, mostly associated with the nervous system.

Question 28

define smpathogonia

Answer 28

Neural crest cells that migrate to a region that will become the sympathitic ganglia.

Question 29

Define chromaffin cells

Answer 29

sympathogonia that migrate to the center of the cup becoming the medullary regionof adrenal (stain brown w/ chrome salts, hence the name).