Parathyroid, Adrenal Gland, Pancreas, Thymus, Testis, Ovary

1. By-
Dr. Dinesh C. Sharma
Head, Zoology
dr_dineshsharma@hotmail.com
1

2. 2

3. There are 2 pairs small gland (.5gm), lying burred in
thyroid dorsally.
Hormone of these glands is called parathoromone
or Collips Hormone,
Parathoromone, a peptide composed of 84 amino
acids.
3

4. Parathoromone (PTH) and thyroid hormone Calcitonin
work antagonistically to regulate the plasma calcium
and phosphate levels.
PTH increase calcium in our body fluids (ECF); thus
it is antagonistic to Calcitonin; but synergistic to
Vitamin ‘D’ (Calciferol). PTH also decreases
phosphate level.
The activity of the parathyroid gland is controlled by
the simple negative feedback mechanism.
Calcium in our body (1kg) is stored in bones, where
from it is released by decalcification; the PTH
promotes decalcification of bones to increase calcium
in ECF; and it also decrease excretion of calcium by
kidney tubules.
4

5. Calcium is required for muscle contraction,
and due to Hyposecretion of PTH; which
reduces calcium level; tetany (sustain
muscle contraction) takes place.
Hypersecretion of PTH causes too much
decalcification of bones due to which they
become soft and weak this condition is
called Osteoporosis or melting of bones.
Manifestations of PTH
5

6. 6

7. Adrenal glands are 1 pair lying
attached with anterior border
of kidney (in mammals); so
they are also called Supra
renal glands or Renal caps.
Each adrenal has two parts are
basically different and
independent
Outer –Cortex-orginates from
-Mesoderm
Inner-Medulla-orginates
from-Ectoderm (or nervous
tissue)
Adrenal is called dual origin
gland
7

8. 8

9. The adrenal cortex
It is the outer part of the adrenal gland and forms about 80
% of the gland.
It secretes steroid hormones . It is divided into three
distinct zones:
Zona Glomerulosa, the outermost layer, secretes
mineralocorticoids, aldosterone, desoxycorticosterone and
corticosterone . They maintain Na+
and K +
balance and
ECF volume
Zona Fasciculata : is the middle widest zone and secretes
glucocorticoids : cortisol and corticosterone that have
widespread effects on carbohydrate and protein metabolism
Zona Reticularis : is the innermost layer and secretes
mainly sex hormones, dehydroepiandrosterone ( DHEA ),
androstenedione (androgens)and small amounts of
estrogen.9

10. 10

11. Hormones of Adrenal Cortex
It produces near 30 hormones which are grouped in to
three
Glucocorticoid-Cortisol
Mineralocorticoid-Aldosterone
Androgens-Testosterone
Cortisol-is the chief Glucocorticoid which is associated
with the carbohydrate metabolism in several ways.
Aldosterone- is the chief Mineralocorticoid which
controls level of sodium in our body. Salts holds water in
our body; due loss of salts dehydration of body takes place
Testosterone is the chief androgen this promotes maleness
11

12. Actions of cortisol
On carbohydrate metabolism :
1- Stimulation of gluconeogenesis by the liver from amino acids.
It decreases glucose utilization (anti insulin action).
2- Increased gluconeogenesis leads to the build up of sufficient
glycogen.(all lead to hyperglycemia& make diabetes worse).
On protein metabolism:
1- Cortisol reduces protein synthesis &increases protein
catabolism in all body cells except liver cells which ↑synthesis.
2- It increases plasma amino acid level& plasma proteins..
3- It inhibits amino acid transport to extrahepatic cells and
stimulates amino acid transport into liver cells.
On fat metabolism:
1-Cortisol has a lipolytic action.it inhance lipolytic effect of
catecholamines.it increase FA mobilization from adipose tissue
2-It increases FFA in plasma.
12

13. Actions of cortisol
Effect on vascular system:
Cortisol is required for the maintenance of
normal arterial blood pressure in response to the
vasoconstrictor effect of catecholamines
(permissive action). It decrease endothelial
permeability of blood vessels.
Effects of cortisol on bone & calcium metabolism:
Long use of cortisol lowers plasma calcium by
decreasing its absorption from the intestine, it
increases its renal excretion. it decreases bone
formation& increases resorption causing
osteoporosis.13

14. Effect on Kidney:
Cortisole is essential for rapid excretion of excess
water load, as it inhibits ADH secretion and action.
Functions of cortisole in stress:
Cortisole is required for catecholamines to exert
their pressor and lipolytic actions.
It increases FFA that are important as emergency
energy source, and raises blood glucose level
together with catecholamines to protect against
hypoglycemia.
14

15. Effect on skeletal muscles
It is essential for maintenance of muscle activity, great excess of
cortisol the muscles become very weak due to protein catabolism
Effect on nervous system:
Changes in cortisol levels affect certain sensations and higher
functions as concentration, memory & intellectual performance
(these effects may be through modulation of neurotransmitters in
the reticular activating system& ↑sensitivity of ß-receptors)
Anti – Inflammatory Effects of Cortisole:
Cortisol stabilizes the membranes of lysosomes so prevents the
release of their proteolytic enzymes.
It diminishes vasodilation.it decreases release of histamine&
prostaglandins.
It decreases migration of white blood cells into the inflammed
area.
It decreases capillary permeability& inhibits fibrosis so prevents
adhesions.15

16. Effect of cortisole on blood cells and immunity:
Cortisole decreases the number of circulating eosinphils and
the number of lymphocytes (T lymphocytes) mainly. It
increase production of RBCs.
It increases number of neutrophils (but inhibits their
function).
It inhibits production of interleukin 2 (IL-2) by lymphocytes.
It antagonizes the synthesis, secretion and actions of
interleukin 1.
High concentrations of glucocorticoids interfere with
antibody production from B-lymphocytes. long use causes
atrophy of lymphoid tissue…
N.B.
Large doses of glucocorticoids can lead to fulminating
infection.
On the other hand, this ability of glucocorticoids to suppress
immunity makes them useful in prevention of immunological
rejection of transplanted organs.
16

17. Regulation of cortisol secretion
1.Hypothalamic regulation:it produces cortico-tropin
releasing factor(CRF).
2.Pituitary regulation: it produces ACTH in response
to CRF .ACTH causes formation of adrenocortical
hormones.
3.Negative feed-back: cortisol has direct –ve feed back
effect on hypothalamus to decrease CRF& on
pituitary to decrease secretion of ACTH.
4.Effect of physiological stress on ACTH secretion:
Physical& mental stress can lead to increase cortisol
secretion within minutes via increase ACTH.
17

18. Circadian rhythm of glucocorticoid secretion
Cortisol is high in the early morning but low in
the late evening, this is due to a 24 hour cyclic
alteration in signals from the hypothalamus.
When ACTH is secreted from ant.pituitary, other
hormones are also secreted : MSH., lipotropin &
endorphin.(their normal levels are not significant,
but if secretion is high, MSH causes melanocytes
to form melanin pigments, ACTH has also
melanocyte stimulating effect.
18

19. Pattern of cortisole level during the day
19

20. 20

21. Relative potency of cortisole and some synthetic steroids
21

22. Pattern of cortisole and ACTH level during the day
22

23. Effect of stress on cortisole secretion
23

24. Control of cortisole secretion
24

25. Manifestations of hypercortisism
25

26. 26

27. Cushing’s disease
A patient with Cushing’s disease before and after subtotal adrenalectomy
27

28. Actions of aldosterone
Aldosterone increases the reabsorption of Na+
from
urine, sweat, saliva, gastric juice and colon.
It stimulates secretion of K +
by the kidney.
Because H2O is passively reabsorbed with Na +
,
there is no increase in plasma Na +
concentration.
so ECFV expands in an isotonic manner.
 Aldosterone also causes H +
to be secreted
into renal tubules.
28

29. Control of aldosterone level
Renin- angiotensin system
Atrial natriuretic peptide
Plasma k+ level
Role of ACTH
Plasma Na+ level
29

30. Effect of renin- angiotensin system on aldosterone secretion
Angiotensin II is responsible for increased
synthesis & release of aldosterone from cellsof
zona glomeriolosa .the level of renin releaseFrom
juxta glomerular apparatus affects the level of
aldosterone.
Effect of potassium ion conc.on aldosterone
secretion: increase in K+ conc. causes direct stim
of zona glomerulosa to increase aldosterone
secretion with excessive excretion of potassium in
urine, so its conc. returns to normal level.
30

31. Effect of decreased Na+ on aldosterone secretion
1-Lack of Na+ inhance aldosterone secretion from zona
glomerulosa.
2-Lack of Na+ causes retention of K+ which stimulates
aldosterone secretion.
3-Lack of Na+ leads to decreased ECF volume which causes↓
CO& ↓ renal blood flow →formation of angiotensinII which
stimulates aldosterone secretion.
4-Lack of Na+ stim. the anterior pituitary to produce what
is called the unidentified pituitary factor that stimulate the
suprarenal to produce aldosterone.
ACTH: has a permissive role on aldosterone secretion and all
the above regulatory factors,
31

32. Actions and control of aldosterone
32

33. Addison’s disease
33

34. 34

35. 35

36. 36

37. Three hormones are concerned with regulation of calcium metabolism:
1,25-dihydrocholecalcifirol(a steroid hormone formed from
Vitamin D :it is important in calcium absorption at the
intestine.
Parathyroid hormone (secreted from parathyroid gland ): it is
Calcium ions elevating hormone in extracellular fluid &
phosphate lowering effect by its effect on bones, kidney& GIT.
Calcitonin secreted from perifollicular cells of thyroid gland:
It reduces blood calcium ion.
All the three hormones operate to maintain the constancy of
calcium level in the body fluids .
Glucocorticoids, growth hormone, estrogen and various other
hormones also affect calcium metabolism.
37

38. Adrenal Medulla
It is an extension of sympathetic
nervous system
Its cells are called chromaffian cells
It is origanted from nervous tissue
It is ectodermal
38

39. Hormones of Adrenal medulla
•Two hormones are produced by Adrenal medulla
• Adrenalin or Epinephrine
• Nor-adrenalin or Nor-epinephrine
•Adrenalin form 80% part of medulla secretion. It is also
called as emergency gland or gland of 3F (Fight, Flight,
Fright), because its hormone are required in state of
emergency.
•These hormone increase Heart beat, BP, breathing rate
glucose level etc for the release of more energy to overcome
the emergency
•Nor-adrenalin is slightly different because it brings about
contraction of basal blood vessels to withdraw blood from
there to muscles
39

40. 40

41. Pancreas
This is a mixed gland
Leaf shaped
Found in dudoneum
98 % is Exocrine part
made up of acini which
produce enzmes
2% Endocrine part made
up of Islets of
Langerhans, which
produce hormone
41

42. Acini
Islets of
langerhans
Capsule
Alpha cells
Beta cells
Delta cells
42

43. Three types cells are found in Islets of Langerhans
Alpha cells- 20%- Produce Glucagon
Beta cells- 75%- Produce Insulin
Delta cells 5%
Most numerous are beta cells which produce
insulin, whose relationship with diabetes mellitus
was first found by Mehering and Minkovsky in
1889.
Bating & Best in 1920 extracted insulin from
Bovine (Cow) pancreas and treatment of diabetic
become possible
Molecular structure of Insulin was given by
Sanger in 195343

44. Insulin
Insulin is decrease level of glucose in blood.
Normally 80-100mg/dl glucose found in blood.
Loss of insulin increases this level called as
hyperglycemia due to which glucose starts passing out in
urine-Glycosuria. These two are symptoms of diabetes
mellitus
In tissue or cells deficiency of glucose occur, and they
begin oxidation of proteins and fats for energy
production; due to this, toxic ketoacids (keto bodies) are
produced.
Regular intake of insulin is required for the patient of
diabetes mellitus.
44

45. Glucagon
Glucagon was discovered by
Kimbel and Murlinin in 1922;
its function is antagonistic to
insulin i.e. increase blood
glucose level.
45

46. Insulin Shock
Over dose of insulin reduces
glucose level too much, and
brain doesnot get it, so person
become unconscious; this is
called insulin shock.
This is advised to take insulin
after meal
46

47. 47

48. Thymus
Thymus is bi-lobbed gland located
between heart & sternum.
This is called founder of immunity,
because lymphocytes are initially
produced by this gland only, later
they are produced at other places-
tonsils, spleen, lymph nodes etc.
Thymus become vestigial in
adulthood.
Hormone produce by thymus to
stimulate lymphocytes is called
Thymosin
Functional in
young stage
Vestigial in
Adult hood
48

49. 49

50. Testis
Between Semenifarous
tubule in the connective
tissue clusters of lyding
or interstitial cells are
found.
Theses cells on
stimulation by ICSH of
pituitary themselves
produce a Testosterone,
whose function is to
promote secondary
sexual characters of male
Tunica albuginia
Sertoli cell or
Nurse cell
Semenifarous
tubule
Sperms
Interstitial cells
Or cells of leyding
50

51. ANDROGENS
prototype is testosterone (produced by
interstitial cells of testis)
main function: development and
maintenance of primary and secondary sex
characteristics in males (androgenic)
protein retention (anabolic action)
other naturally occuring androgens:
androsterone, isoandrosterone,
dehydroandrosterone,
dehydroisoandrosterone
51

52. Physiological effects of testosterone
pubertal transformation:
1. enlargement of testes, penis and scrotum
2. pubic and axillary hair
3. bone growth
4. red cell mass increase
5. skeletal muscle mass increase
6. larynx enlarges - deepening of the voice
7. increase in sebaceous glands - often cause of
acne
8. beard development
52

53. Natural androgens
O
OH
HH
H
TESTOSTERONE
O
OH
HH
H
H
DIHYDROTESTOSTERONE
53

54. 54

55. Testosterone products
testosterone in aqueous suspension (short-
acting)
testosterone propionate in oil
testosterone enanthate in oil (Delatestryl)
testosterone cypionate in oil (Depotest)
testosterone pellets (Testopel)
testosterone transdermal system
(Androderm)
55

56. 56

57. Uses for Androgens
Replacement therapy in hypogonadism
delayed puberty
cryptorchidism
metastatic breast cancer in women
postpartum breast pain/engorgement
male climacteric
57

58. Ovaries
Ovaries produce three hormones-
Estrogen- Produce by Graffian follicle
Progesterone- Produce by Corpus
luteum
Relaxin- Produce by Corpus albicans58

59. • Follicle of ovary when become mature produce
estrogen, whose function is to promote secondary
sexual characters in female
• After ovulation the Graffian follicle become Corpus
luteum; which produce progesterone, whose function
is to maintain pregnancy. At the time of birth it
produce relaxin, which helps in child birth
• In absence of pregnancy Corpus luteum reduced to a
scar called as Corpus albicans
Graffian follicle Corpus luteum
Corpus albicans
Ovum
59

60. ESTROGENS
estrogens include the natural hormones
as well as semi-synthetic and synthetic
(stilbene) agents
estrogens are used as hormone-
replacement therapy (menopause), in
oncology and as contraceptives
most estrogen in the female is
produced in the ovaries by the theca
interna and the granulosa cells of the
follicles
60

61. 61

62. Actions of estrogens
1. on sexual organs (primary and secondary sexual
characteristics)
2. ovaries : stimulate follicular growth; small doses
cause an increase in weight of ovary; large doses
cause atrophy
3. uterus: endometrial growth
4. vagina: cornification of epithelial cells with
thickening and stratification of epithelium
5. cervix: increase of cervical mucous with a
lowered viscosity (favoring sperm access)
62

63. Development and maintenance of internal
(fallopian tubes, uterus, vagina), and
external genitalia
skin: increase in vascularization,
development of soft, textured and smooth
skin
bone: increase osteoblastic activity
electrolytes: retention of Na+, Cl- and water
by the kidney
cholesterol: hypocholesterolemic effect
63

64. Thyroid & Reproduction
Hypothyroidism and reproductive malfunction
Male Female
Hypogonadism Irregular
Oligospermia Menstruction
Azoospermia

65. Thyroid Hormone Protein synthesis increases in
Granulosa Cell
Graffian Cells
Leyding Cells

66. Oral Contraceptives
4 types:
monophasicmonophasic: Loestrin, Levlen, Levora, Levlite, Desogen,
Lo/Ovral, Ortho-Cept, Nordette, Demulen, Ovcon,
Modicon, Zovia, Loestrin, Apri, Microgestin, Yasmin, Ortho-
Cept, Levora, Alesse
biphasicbiphasic: Ortho-Novum 10/11, Nelova 10/11, Necon 10/11,
Jenest-28, Mircette
triphasictriphasic: Ortho-Novum 7/7/7, Tri-Norinyl, Tri-Levlen,
Triphasil, Trivora-28, Estrostep
progestin-onlyprogestin-only: Micronor, Nor-QD, Ovrette
66

67. Generics
Examples of Generic Oral Contraceptives
• Apri (same as Desogen and Ortho-Cept 28)
• Aviane (same as Alesse-28)
• Lessina (same as Levlite 28)
• Necon (same as Ortho-Novum 1/35)
• Ogestrel (same as Ovral)
• Sprintec (same as Ortho-Cyclen-28)
• Microgestin Fe (same as Loestrin Fe)
• Kariva (same as Mircette)
• Enpresse (same as Triphasil-28)
67

68. 68

69. Estrogen products69

70. 70

71. Raloxifene (Evista)
71

72. 72