The pituitary gland, also known as the hypophysis, is located at the base of the brain. It is divided into the anterior and posterior lobes. The anterior lobe secretes growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, follicle stimulating hormone, luteinizing hormone, and prolactin. These hormones regulate important body functions like growth, metabolism, reproduction, and lactation. The posterior lobe stores and releases oxytocin and vasopressin, which are produced in the hypothalamus and help regulate water balance, uterine contractions during childbirth, and milk ejection. The pituitary gland acts as a master gland that controls other endocrine glands via negative feedback loops.

1. Sistem endokrin

2. Di akhir sesi pembelajaran pelatih
dapat :
1.Menghuraikan lokasi kelenjar­kelenjar sistem
endokrina.
2.Menyenaraikan kelenjar­kelenjar sistem endokrina.
3.Menyatakan fungsi kelenjar
a.Pitutari
b.Tiroid
c.Paratiroid
d.Adrenal
e.Pineal
f.Timus

3. Sistem endokrina dikelaskan kepada dua:
1. Kelenjar endokrina
­ sel­sel, tisu­tisu danorgan­organ yang
merembeskan hormon ke dalam cecair badan
secara langsung tanpa duktus.
2. Kelenjar eksokrina
­ bhg organ yg merembeskan penghasilan ke
dlm dan permukaan badan melalui duktus.

4. Nama kelenjar Lokasi
1 kelenjar Terlekat pada hipotalamus –
pituitari sella turcica ( pelana turki )
1 kelenjar tiroid Di bawah larink , depan trakea
4 kelenjar Di permukaan posterior tiroid
paratiroid
2 kelenjar adrenal Di atas pada setiap ginjal

5. Nama kelenjar Lokasi
1 kelenjar pineal Di antara hemisfera serebral
Di permukaan posterior ligamen
2 ovari lebar, melekat pada mesovarium
2 testis Di dalam kaviti skrotum
Sel-sel islets Bertaburan di pankreas
langerhans

6. Nama kelenjar Lokasi
Plasenta Di uterus semasa ibu hamil
Timus
Di mediastinum
Gastrik & mukosa Di dalam kaviti abdomen
intestinal

7. Klasifikasi Hormon
 Endokrina  hormon yang dikeluarkan ke
dlm peredaran darah dan hanya berinteraksi
dengan sel - sel sasaran .
 Parakrina  hormon yang bertindak ke atas
sel - sel yang terdekat .
 Autokrina  hormon yang dikeluarkan dan
seterusnya bertindak ke atas sel - sel yang
mengeluarkanya .

8. The Endocrine Glands

9. The Endocrine Glands & their Hormones
Basic principles in hormone actions :
This helps maintain HOMEOSTASIS

10. The Endocrine Glands & their Hormones
Pineal Gland
- Main hormone secreted
MELATONIN
- Role Melatonin
-- Mammals : Regulate
reproductive activity in
response to environmental
light cycles
e . g . Some mammals mate in
summer ( lot of light ), whi
others mate in winter ( lo
light ).

11. The Endocrine Glands & their Hormones
Thyroid Gland
- Produces 3 main hormones
- Triiodothyronine ( T3 )
- Thyroxine ( T4 )
Regulate body metabolism and are
important in bone growth and maturati
of the brain
- Congenital lack of thyroid hormones :
Cretinism .
- Calcitonin
Acts by reducing calcium levels

12. The Endocrine Glands & their Hormones
Parathyroid Gland
- Parathyroid Hormone
Raises Blood Calcium
( antagonize Calcitonin )
This hormone acts on bone , kidney
and the gut

13. The Endocrine Glands & their Hormones
Thymus Gland
- Thymosin :
Stimulates the production of Lymphocyte
- Thymostatin :
Inhibits the production of Lymphocytes
Thymus : Important for the neonatal
production of antibodies
Thymus : Gland being at the center
of endocrine , neural , and immune
systems

14. The Endocrine Glands & their Hormones
Heart
- Granular cells in the heart muscle
secrete Atrial Natriuretic Factor ( A
.. ANF : Regulates blood pressure ,
blood volume , and excretion
of water , sodium and
potassium
.. ANF : Also a neuropeptide in
the brain

15. The Endocrine Glands & their Hormones
Gastrointestinal Hormones
- The mucosa of the GI tract secretes
a
dozen PEPTIDE hormones
3 most important :
1 . Secretin :
Secreted in the small
intestine Stimulates the secretion
of pancreatic bicarbonate and has
other functions on digestion
2 . Gastrin:
Secreted in the walls of
stomach Stimulate
hydrochloric acid secretion
stimulate
pancreatic enzyme secretion
3 . Cholecystokinin :
Secreted in the small intestine
Stimulate gall
bladder contraction Stimulate

16. The Endocrine Glands & their Hormones
Pancreas
Endocrine cells in the pancreas
secrete
2 major types of hormones
1 . Insulin :
Secreted in response to
increase in blood glucose
levels ; So insulin LOWERS
glucose levels by INCREASING
glucose UPTAKE in cells where
it is stored as glycogen .
2 . Glucagon:
Increases blood glucose
levels by
stimulating the conversion

17. A parte : Insulin & Diabetes
Insulin & Diabetes
Diabetes: Hyperglycemia , ie .
Elevated Blood Sugar
2 Types : The distinction is based upon
whether the blood sugar problem is
caused by insulin deficiency ( Type 1 )
or insulin resistance ( Type 2 )
Type 1 - Insulin Deficiency: There is not
enough insulin produced by the pancreas
so the patient must inject insulin on a dail
basis
Type 2 - Insulin Resistance: There is plenty of
insulin but the cells of the body are resist
to its action so , increase in blood sugar
This form is controlled by a strict diet

18. The Endocrine Glands & their Hormones
Adrenal Glands
2 parts : Medulla & Cortex
Adrenal Cortex :
3 categories of steroid
hormones
1 . Mineralocorticoids
2 . Glucocorticoids
3 . Sex Steroids
Adrenal Medulla
1 . Adrenaline
2 . Noradrenaline

19. The Endocrine Glands & their Hormones
Adrenal Cortex
Androgen Influence sexual differentiation
and bodily changes during pubert
Estrogen
Stress Hormone , converts stored
proteins to carbohydrate during
Stress . Anti inflammatory and
Immunosuppressive functions .
If there is a sodium
deprivation ,
Aldosterone is secreted and
acts
to increase reabsorption of
sodium ions ( NA +) in the
kidneys
salivary glands , and sweat
glands .

20. The Endocrine Glands & their Hormones
Adrenal Medulla
line : Released following
stress due to environmental
extremes ; Increases heart
rate and blood glucose levels
so , increases the amount of work
the muscles
enaline : As Adrenaline , act as a NT
( neuro transmiter ) in the brain Periphery ; increase blood pre
and constrict blood vessels ( noradrenaline , stress , and heart disease …

21. The Endocrine Glands & their Hormones
Gonads ; Testes
The male gonads : produces
Androgens
Primary androgen = TESTOSTERONE
Other androgen :
Dihydrotestosterone
Androstenedione
Testosterone: Important for
masculinization
Control of sperm production
Development of male sexual
characteristics
Activation of sexual and
aggressive behaviors

22. The Endocrine Glands & their Hormones
Gonads ; Ovaries
2 major classes of hormones
ESTROGENS
PROGESTINS
Primary ESTROGEN : Estradiol
others : Estriol , Estrone
Synthetic estrogens : Birth control pil
Estrogens : - Development of sexual
characteristics at puber
- Influence metabolic rat
- Influence sexual and
maternal behavior

23. The Endocrine Glands & their Hormones
Gonads ; Ovaries
PROGESTIN: Progesterone
- Stimulates breast and uterine
enlargement at puberty & during
menstrual cycle
- Maintains pregnancy ( inhibits menstru
cycle during pregnancy )
Other hormone released at the end of
pregnancy : Relaxin
Acts to prepare the birth canal .
trogen and Progesterone act in synergy .

24. The Endocrine Glands & their Hormones
Placenta
- Hormones secreted by the fertilized egg
( Used in pregnancy tests )
Human Chorionic Gonadotropin ( HCG )
Act by keeping progesterone high at the
beginning of a pregnancy
Human Placental Lactogen ( HPL )
Stimulates the mammary glands to begin
to secrete milk

25. The Pituitary Gland & its Hormone
Also called
the HYPOPHYSIS

26. The Pituitary Gland & its Hormone
- Attached to the HYPOTHALAMUS
- Secretion of the pituitary hormone
is regulated by hypothalamus
- HYPOTHALAMIC - PITUITARY
connection

27. The Pituitary Gland & its Hormone
ANATOMY
ADENOhypophysis NEUROhypophysis
- 3 parts
--> Anterior Lobe
- pars distalis
--> Intermediate Lobe
- pars intermedia
--> Posterior Lobe
- pars nervosa
(“ neural ” cells )
direct extension
of the
hypothalamus

28. The Pituitary Gland & its Hormone
PVN SON
- Neuroscretory Cells
- Paraventricular nucleus ( PVN )
- Supraoptic nucleus ( SON )
- Hormones secreted
AXONS
-OXYTOCIN
-VASOPRESSIN
Attaches the
hypothalamus to the
pituitary. Also called
the Infundibulum
Neurohypophysis

29. The Pituitary Gland & its Hormone
PVN SON
OXYTOCIN & VASOPRESSIN
- Are really HYPOTHALAMIC
hormones
- OXYTOCIN :
AXONS
2 main functions
--> promotes uterine contractio
Attaches the --> stimulates milk ejection fr
hypothalamus to the mammary glands during
pituitary. Also called lactation
the Infundibulum
Neurohypophysis

30. The Pituitary Gland & its Hormone
PVN SON
- VASOPRESIN :
--> Antidiuretic hormone
--> Raises blood pressure
AXONS --> promotes water reabsorption
by kidneys
--> centrally : may promote
memory
Attaches the
hypothalamus to the - Binding proteins for both
pituitary. Also called oxytocin & vasopressin
the Infundibulum
--> Neurophysins
Neurohypophysis

31. The Pituitary Gland & its Hormone
ADENOHYPOPHYSIS ( ANTERIOR )
AXONS Mechanism for release of hormones
True endocrine gland because
release hormone in the bloodstream
( hypophysal portal system )
Attaches the
hypothalamus to the
pituitary. Also called
the Infundibulum
Adenohypophysis

32. The Pituitary Gland & its Hormone
1 . Neurosecretory cells of the
Median eminence
hypothalamus release their hormon
at the median eminence
2 . Hormones circulate in bloodstream
3 . Carried to the adenohypophysis
4 . Stimulates secretion of other
hormones from the adenophysis
5 . These hormones are then released
in the bloodstream to reach
their target cells .

33. The Pituitary Gland & its Hormone
Adenohypophysis : 6 hormones
1. Growth Hormone ( GH )
( also called ‘ somatotropin ’)
AXONS …’ tropic ’= stimulating effect
GH = promotes growth in almost
all body cells
Attaches the
hypothalamus to the lot of attention for degenerativ
A
disease …..
pituitary. Also called
the Infundibulum -Alzheimer
-Parkinson
- Anti - Aging etc .
Adenohypophysis

34. The Pituitary Gland & its Hormone
Adenohypophysis : 6 hormones
2 . Adrenocorticotropic Hormone
ACTH
Role : Stimulates synthesis and
AXONS release of glucocorticoi
hormones
‘ Hypothalamic - pituitary - adrenal
Attaches the Axis ’
hypothalamus to the
pituitary. Also called
the Infundibulum
Adenohypophysis

35. The Pituitary Gland & its Hormone
Adenohypophysis : 6 hormones
3 . Thyroid Stimulating Hormone
TSH
Role : Stimulates the synthesis and
AXONS release of thyroxine ( T4 )
and triiodochyronine ( T3 )
from the thyroid .
Attaches the
hypothalamus to the
pituitary. Also called
the Infundibulum
Adenohypophysis

36. The Pituitary Gland & its Hormone
Adenohypophysis : 6 hormones
3 last hormones =
…. gonadotropic hormones
4 . Follicle stimulating hormone ( FS
AXONS Role : In both sexes , promotes the
development of reproductive
cells ( gametes ) and
promotes secretion of
Attaches the gonadal hormones
hypothalamus to the
Males : stimulates sperm production
pituitary. Also called
the Infundibulum Females : stimulates growth of
primary follicle of ovary
Adenohypophysis

37. The Pituitary Gland & its Hormone
Adenohypophysis : 6 hormones
3 last hormones =
…. gonadotropic hormones
5 . Luteinizing hormone ( LH )
AXONS Role :
Female : Stimulates ovulation and
formation of progesterone -
Attaches the secreting cells
hypothalamus to the
Males : Stimulates cells that secret
pituitary. Also called
the Infundibulum androgens ( e . g . testosterone )
Adenohypophysis

38. The Pituitary Gland & its Hormone
Adenohypophysis : 6 hormones
3 last hormones =
…. gonadotropic hormones
6 . Prolactin ( PRL )
AXONS Role : Initiates milk synthesis in
mammary glands
Other functions related to
Attaches the growth & parental behavior
hypothalamus to the
Interaction with serotonin also
pituitary. Also called
the Infundibulum( important in depression )
Adenohypophysis

39. The Pituitary Gland & its Hormone
Non traditional hormone from the
adenohypophysis
--> beta - endorphin
Derivative from POMC
AXONS
POMC : synthesized in the pars
distalis and pars intermedia
Attaches the Broken down into ACTH , MSH &
hypothalamus to the beta - endorphins by enzymes
pituitary. Also called
the Infundibulum
Adenohypophysis

40. The Pituitary Gland & its Hormone
Beta - Endorphin : Role to play in --> Analgesia
--> Learning and Memory
--> Psychiatric diseases
--> Feeding , Thermoregulation ,
--> Blood pressure
--> also called the ‘ drug of the jogger ’…..

41. The Pituitary Gland & its Hormone
Synthesize the hormone called
Melanocyte stimulating hormones
which acts in amphibian to change
skin color
AXONS
Attaches the
hypothalamus to the
pituitary. Also called
the Infundibulum

42. TERIMA KASIH