Block 1 Histology Md1 Endocrine System 1 Part C

Front 1

Five functional cell types are identified in the pars distalis on the basis of =

Back 1

immunocytochemical reactions: ***
(*** know all 5)

Nm them =

Hint 1

SOMATOTROPES
LACTOTROPES
THYROTROPES
GONADOTROPES
CORTICOTROPES

Front 2

Nm the aka
&
initials
&
3rd slide name Hormones produced

SOMATOTROPES

Back 2

GH cells)
- acidophilic
- Somatotropin or growth hormone;

acts on growth of long bones via somatomedins (insulin like growth factor 1) synthesized in liver; numerous secretory granules;

Hint 2

Stimulated by Growth hormone releasing hormone (GHRH); inhibited by somatostatin.

Front 3

LACTOTROPES

Back 3

MAMMOTROPES (PRL cells)-

Hint 3

acidophilic
Prolactin
PRH
PIH

)- acidophilic - Prolactin, promotes milk secretion; increases mammary gland in size during pregnancy and lactation; PRH and PIH (prolactin releasing and inhibiting hormones).

Front 4

THYROTROPES

Back 4

TSH cells

basophilic

Hint 4

- Thyrotropin
- TSH,

stimulates thyroid hormone synthesis, storage and liberation; small granules,
TRH - thyrotropin-releasing hormone.

Front 5

GONADOTROPES

Back 5

(FSH and LH cell)
basophilic

Hint 5

(FSH and LH cell) - basophilic, FSH


(follicle stimulating H) and LH (luteinizing hormone); FSH promotes ovarian follicle development. and estrogen secretion in women and stimulates spermatogenesis in men. LH promotes ovarian follicle maturation and progesterone secretion in women and Leydig cell stimulation and androgen secretion in men; GnRH - gonadotropin releasing H; FRH-follicle releasing H and LRH – lutein releasing H.

Front 6

CORTICOTROPES

Back 6

(ACTH cells)
basophilic

Hint 6

Corticotropin (ACTH),
CRH

Front 7

SOMATOTROPES

Back 7

- acidophilic - Somatotropin or growth hormone; acts on growth of long bones via somatomedins (insulin like growth factor 1) synthesized in liver; numerous secretory granules; Stimulated by Growth hormone releasing hormone (GHRH); inhibited by somatostatin.

Front 8

LACTOTROPES

Back 8

or MAMMOTROPES (PRL cells)- acidophilic - Prolactin, promotes milk secretion; increases mammary gland in size during pregnancy and lactation; PRH and PIH (prolactin releasing and inhibiting hormones).

Front 9

THYROTROPES

Back 9

basophilic - Thyrotropin - TSH, stimulates thyroid hormone synthesis, storage and liberation; small granules, TRH - thyrotropin-releasing hormone.

Front 10

GONADOTROPES

Back 10

) - basophilic, FSH (follicle stimulating H) and LH (luteinizing hormone); FSH promotes ovarian follicle development. and estrogen secretion in women and stimulates spermatogenesis in men. LH promotes ovarian follicle maturation and progesterone secretion in women and Leydig cell stimulation and androgen secretion in men; GnRH - gonadotropin releasing H; FRH-follicle releasing H and LRH – lutein releasing H.

Front 11

CORTICOTROPES

Back 11

- basophilic - Corticotropin (ACTH), stimulates secretion of adrenal cortex hormones, large granules, CRH - corticotropin-releasing hormone.

Front 12

CONTROL OF PARS DISTALIS:
Main mechanism use =

Back 12

peptide hormones =

produced in =

Hint 12

aggregates of neurosecretory cells and stored in median eminence.

Front 13

CONTROL OF PARS DISTALIS:

. Hypothalamic releasing/inhibiting hormones
the brain affect the function of =

Back 13

hypophysis --and other organs.

Hint 13

Front 14

CONTROL OF PARS DISTALIS:

Direct effect of hormones from stimulated

Back 14

endocrine cells

on the release of peptides from the _______________ and the ___________ Feedback mechanism.

Hint 14

median eminence

pars distalis.

Front 15

PARS TUBERALIS

Back 15

FSH
LH
ACTH

Hint 15

funnel-shaped region surrounding the infundibulum of neurohypophysis. Most of the cells secrete gonadotropins (FSH and LH) or ACTH and are arranged in cords alongside the blood vessels.

Front 16

PARS INTERMEDIA:

Back 16

The pars intermedia, which develops from the dorsal portion of Rathke's pouch is, in humans, a rudimentary region made up of cords and follicles of weakly basophilic cells that contain small secretory granules. α-Melanocyte-stimulating hormone (α -MSH) is probably produced in the intermediate zone, and probably also by basophils of the pars distalis.

Front 17

Neurohypophysis

consists of three histologic components

Back 17

1. Pituicytes
2. Unmyelinated axons
3. Fenestrated capillaries

Front 18

1. Pituicytes
2. Unmyelinated axons
3. Fenestrated capillaries

come from =

Back 18

Neurohypophysis

Front 19

1. Pituicytes

Back 19

resembling astrocytes, provide support to the axons.

Front 20

Neurohypophysis

resembling astrocytes, provide support to the axons.

Back 20

1. Pituicytes

Front 21

Neurohypophysis

2. Unmyelinated axons

Back 21

derived from neuroendocrine cells of the supraoptic and paraventricular nuclei, make up the infundibulum and form the hypothalamohypophysial tract.

Front 22

Neurohypophysis

derived from neuroendocrine cells of the supraoptic and paraventricular nuclei, make up the infundibulum and form the hypothalamohypophysial tract.

Back 22

2. Unmyelinated axons

Front 23

Neurohypophysis

2. Unmyelinated axons

Back 23

Axons, with bulging intermittent segments and terminals (called =)

secretory products (the neurophysin-hormone complex), are found in the pars nervosa (neural lobe).

Both the supraoptic and paraventricular nuclei contain neurons synthesizing ADH and oxytocin.

Hint 23

Herring bodies

Front 24

Neurohypophysis

3. Fenestrated capillaries are derived from the

Back 24

inferior hypophysial artery.

Front 25

Neurohypophysis
derived from the
inferior hypophysial artery.

Back 25

Fenestrated capillaries

Front 26

Pituicytes
cytoplasmic processes of pituicytes

Back 26

1. surround the axons derived from the neuroendocrine cells.

2. extend between the axon terminals and the basal lamina surrounding fenestrated capillaries

3. retract to enable the release into the blood of secretory granules stored in the axon terminals.

Axons in the neurohypophysis derive from the supraoptic nuclei and the paraventricular nuclei.