The endocrine system is comprised of glands that secrete hormones directly into the bloodstream to regulate bodily functions. Key glands include the hypothalamus, pituitary gland, thyroid gland, parathyroid gland, adrenal glands, pancreas, and gonads. The hypothalamus controls the pituitary gland, which is the "master gland" that regulates most other endocrine glands. Hormones function via negative feedback loops to maintain homeostasis and influence growth, metabolism, fluid balance, mood, and reproduction. Imbalances can result in hypo- or hyperthyroidism, influencing factors like heart rate, weight, and digestion.

1. ENDOCRINE SYSTEM
YOGIC CO- RELATION

2. ENDOCRINE SYSTEM
• Endocrine system is comprised of network of endocrine glands
and also some organs which have an important function w.r.t.this
system
• Endocrine System helps to integrate body systems in conjunction
with the nervous system by regulating and maintaining various
body functions by synthesizing (making) and releasing hormones,
chemical messengers.
• It provides long term regulation and adjustment of homeostatic
mechanisms.
• It also assists the Nervous System in responding to stressful
stimuli

3. Endocrine system helps control …..
the following processes and system.
• Growth and development
• Homeostasis (the internal balance of body systems )
• Metabolism (Body energy levels)
• Cell & tissue metabolism
• Reproduction, birth &lactation
• Response to stimuli(stress and/or injury)
• Absorption of Nutrients
• Water& Electrolyte balance

4. STRUCTURE
There are two types of glands in the body:
1. EXOCRINE - have ducts to carry their secretion to organs
eg. Salivary, sweat, tear glands…
2. ENDOCRINE - Ductless glands :
- secretions direct into blood
- are components of the Endocrine System

5. ENDOCRINE- Ductless glands : are components of Endocrine System
 Produce secretions – hormones- chemical messengers –chemical
signals of the ES
 Released directly into the blood and transported to the organs
through the blood
 Hormones cannot be stored in the glands or body
 Secreted as per requirement
 All secretions except that of the Adrenal Glands controlled by
negative feedback mechanism
The term HORMONE derived from Greek word – “ hormone “ means-
to arouse/excite ENDO – within KRINEIN – to separate

6. POSITIVE & NEGATIVE FEEDBACKS
Hormone regulation mechanisms
POSITIVE FEEDBACK
Process which causes a self amplifying cycle
where a physiological change leadsto an
even greater change in the same direction.
NEGATIVE FEEDBACK Process in which the body senses a change
activates mechanisms to reverse that
change

7. EFFECTS OF POSITIVE & NEGATIVE FEEDBACK CONTROL
NEGATIVE FEEDBACK MAINTAINS POSITIVE FEEDBACK MAINTAINS
Blood Pressure Ovulation
Body Temperature Childbirth
Blood pH Lactation
Blood Sugar Blood clotting

8. Features of Hormones
• Hormone Secretion / Transport / Clearance from blood
• Not stored in body – produced when needed.
• Pulsatile secretions as & when needed
• Blood concentration of hormones is extremely small.
• It ranges from /picogram ( one millionth of one millionth of a gram ) in each
ml of blood ..upto few micrograms ( few millionths of a gram )
• So- basically nano quantities.
• Diurnal variation ( fluctuations during the day )
• Different levels in different individuals
• Works on feedback mechanism
• Some hormones e.g Norepinephrine & epinephrine secreted within seconds
• Some horrmones e.g Thyroxine , GH – may require months for full effect

9. ENDOCRINE GLANDS EXOCRINE GLANDS
They are ductless glands They are glands with ducts
They secrete chemicals called hormones Their secretion may be enzymes, sweat,
oil, or tears
They are transported by the blood to
target cells far away from the source of
production
The ducts transport these secretions to
a region close to the source of
production
eg Adrenal Gland ,Thyroid gland eg. Sweat gland, Salivary gland
,Sebaceous ( oil ) glands etc

10. HORMONES ENZYMES
Secretion of Endocrine Glands Secretions of Exocrine glands
Chemically may be steroids, protein or
amino acid derivatives
Chemically always proteins
Transported by blood Transported by ducts
Reaction occurs away from the site of
secretion in target cells or organs.
Reaction occurs close to the site of
secretion
They may accelerate or inhibit specific
activity
Always accelerate chemical reactions
Their action may be slow or quick Their action is always quick

12. ENDOCRINE GLANDS
• HYPOTHALAMUS: Bridge between Nervous and Endocrine Systems
• PINEAL: is located near the third ventricle of the brain and has a rich
blood supply.
• PITUITARY : It is tiny pea sized, situated in below the mid brain near
optic chiasma it has two lobes anterior and posterior. It is
closely connected with the hypothalamus via portal
circulation.
• THYROID: the largest of all the endocrine glands, situated in the neck in
front of the trachea. It has two lobes on each side.
• PARATHYROID: are four small pea shaped glands attached to and behind the
thyroid.

13. • THYMUS: Located in the chest behind sternum.
Its size starts decreasing around adolescence.
• ADRENAL : These are cup shaped & above each Kidney.
There are two parts, outer cortex and inner medulla.
• PANCREAS: Flattened leaflike structure below the stomach
Has two parts, one is Exocrine and other is Endocrine
Endocrine part is made up of 3 types of cells Alpha, Beta & Delta cells
Beta cells also called a Islets of Langerhans.
• GONADS : Are reproductive glands.
Females- A pair of ovaries is present in the abdomen.
Males - A pair of testes is present in the abdomen.
They are hung outside the body in the lower abdomen, so as to attain
a temperature less than the body

14. HYPOTHALAMUS AND EMOTIONS
• Emotional behavior is an important functions of the nervous system
• Emotional behavior, feelings of pleasure sorrow excitement etc. are
performed by the basal regions of brain called ‘limbic system’
• It has been proved that hormones are responsible for a particular behavior
pattern of the individual & the secretion of hormones is influenced by intense
emotional fluctuations.
• Hormones have a specific & important role in the development of a particular
mood , attitude , temperament & psychological make-up of a person – science
of Psycho-Neuro-Immunology
• Hypothalamus plays an important role in controlling the endocrine glands
through its control on the Master Gland – Pituitary
• Thus Emotions play a big role in the function of the Endocrine System since
emotions are closely linked with the Hypothalamus.
• Emotions affect the Target Organs through the Pituitary- H-P-O Axis.

15. PITUITARY

17. ANTERIOR LOBE POSTERIOR LOBE
PITUITARY GLAND
LOCATION- attached
to the hypothalamus
STRUCTURE - tiny pea
sized- 2 lobes-
anterior & posterior
FUNCTION
PRL-
Prolactin-
helps in
lactation
Antidiuretic
hormone (ADH)
Reduce urine
formation
GH- Growth
Hormone –
regulates normal
body growth
Oxytocin-
contraction of uterus &
related to menstrual cycle
FSH – Follicle
Stimulating Hormone –
Stimulates testes to
produce sperms
&ovaries to produce
ova
TSH – Thyroid
Stimulating
Hormone –
Stimulates thyroid
gland in producing
its hormones
LH- Lutinizing Hormone –
Stimulates testes to
produce testosterone &
ovaries produce
Progesterone &
OestrogenACTH- Adrenocorticotropic
Hormone – stimulates synthesis of
glucocorticoids from adrenal cortex

19. PINEAL GLAND
• Pineal plays an extremely important role in Neuroendocrine Immune Axis
• Comparable to that of hypothalamus to which it is closely connected
• Activity inhibited by stimulation from photoreceptors of retina. Light sensitive
• Light suppresses pineal secretion
• Secretion increases in darkness
• Secretion helps to regulate human “ Wake-Sleep/ Day-night “ cycle
( circadian cycle )

20. production of HORMONE –
MELATONIN
PINEAL
LOCATION – Posterior to
the thalamus –midbrain
STRUCTURE –
small pinecone shape
FUNCTION
Reproductive system -
To suppress gonadotropin secretion from pituitary
Metabolic Rate –
Reduces M.R. in body
Reduces temperature
Antioxidant effect : It is an endogenous antioxidant
Immunity –
Immunostimulant effect.
Stimulates activity of T-Helper cells

21. PINEAL GLAND – HORMONE - MELATONIN
ACTIONS
•Metabolic Rate
•Antioxidant - protects against oxidative damage
•Immunity
•Important for sleep
•Muscle relaxant - relaxes the smooth muscles including
those of the digestive system.
Hence has a tremendous effect on this
system & problems related to this
system

22. Stress – does not stimulate melatonin secretion .
Thus, sympathetic nerve supply of the pineal
seems to have a control independent of most
other components of S.N.S.

23. •He who knows Melatonin knows medicine
–
Say Yu & Reiter

24. Pineal in Yoga
Paramahansa Swamiji Satyanand Saraswati says
It is analogous to a transistorized valve of radio which picks
up electromagnetic waves from a far off broadcasting
station.
……………………………………………………………………………………………
• Associated with Ajna chakra – Telepathy , clairvoyance
• Physical equivalent of third eye
• Seat of Intution
• Eye of illumination

25. THYROID AND PARATHYROID

26. Secretes -
Triiodothyronine(T3)
Thyroxine(T4)
Calcitonin
THYROID GLANDLOCATION – situated on
the lateral & ventral
sides of the trachea just
below the larynx
STRUCTURE – Butterfly
shaped, bi-lobed structure .
The 2 lobes are joined by a
narrow piece of tissue called
Isthmus
FUNCTION
T3 & T4 work together
Regulation of BMR, body temperature, body
weight.
Responsible for normal growth-improves mental
alertness
release controlled by TSH from pituitary thru
stimulation of hypothalamus.
Excitement & anxiety stimulates secretion of TSH
Iodine required for formation of thyroid
hormones
Calcitonin –
Responsible for calcium
metabolism .
Reduces Ca levels in blood

27. Secretes Parathormone (PTH)
Regulation of calcium levels in blood
Works along with calcitonin
PARATHYROID
LOCATION – Attached
to the posterior side
of the thyroid gland
STRUCTURE –
Four small pea shaped
glandFUNCTION
HYPOTHYROIDISM –
Deficiency of calcium –
hypocalcaemia
Tetany – muscle
twitches, spasms,
convulsions
HYPERTHYROIDISM –
Increase in calcium level –
hypercalcemia

28. HYPOTHYROIDISM – DECREASED LEVELS HYPERTHYROIDISM - INCREASED LEVELS
Low Heart Rate Increase in Heart rate
Low blood pressure Increase in Blood pressure
Low respiratory rate Increase in Respiratory rate
Lowers hunger & Lower BMR Increase in Hunger/ increase BMR
Increase in body weight - overweight Loss of weight
Sluggishness in digestive system-leads to constipation Hyper activity of digestive system – loose motions
Lethargy Goiter – enlarge thyroid
Low body temperature Increase body temperature – more sweating
Muscle weakness & Nervousness Tremors in fingers

30. THYMUS GLAND

31. Secretes THYMOSIN Hormone
THYMUSLOCATION – located in
chest behind the
sternum
STRUCTURE – Soft,
triangular shaped organFUNCTION
• Functions as commando to immune system
• Production & supply of antibodies as &
when required
• Alertness
• Immunity & Defense
• Very important for body for fight against
infections
• Growth up to puberty after which it takes a
back stage

33. • 2.
ADRENAL CORTEX
Secretes 3 hormones
1. Mineralocorticoids
2. Glucocorticoids
3. Sex corticoids
ADRENAL MEDULLA-
Secretes
1. Adrenalin or Epinephrine
2. Nor- Adrenalin
3. Dopamine
ADRENAL GLAND
LOCATION – fits like
a cap above each
kidney
FUNCTION
Eg. Aldosterone
1. regulates
metabolism of K+ &
Na+ ions. Stimulates
kidneys to retain Na(
Sodium ) + & excrete
K+ ions
( Potassium )
ROLE OF ADRENALIN
1. Stimulates breakdown of glycogen in
muscles & hence increases glucose
level in blood
2. Increases the contractility of muscles.
3. Helps body to adapt to various
situations such as stress, trauma,
fasting, starvation etc..
4. ‘Emergency hormone’ or
the’ flight or fight Hormone’
STRUCTURE –
outer adrenal cortex –
inner adrenal medulla
Eg. Cortisones
1.Concerned with
carbohydrate &
protein
metabolism 2.
reaction to stress
3. increase in BP
4.Incr in Blood
glucose
5.allergic reaction
decrease
5.Anti Inflamatory
Eg. Androgens
Gondocorticoids – responsible for
secondary sexual characteristics
general growth, healing &
maintenance of body

35. EXOCRINE GLAND – pancreatic
Juice- transported by pancreatic duct to
the duodenun
ENDOCRINE - Cells –
Islets of Langerhans –ALPHA ,BETA ,DELTA
CELLS
hormones – transported by blood –
to target Organs
PANCREASLOCATION - below the
stomach, at the loop of
the duodenum
STRUCTURE – Flattened
Leaf like - three type of
cells alpha, beta and delta
FUNCTION
ALPHA CELLS-
secrete GLUCAGON– converts
glycogen stored in the liver into
glucose. Increases glucose level in
blood
BETA CELLS-
secrete INSULIN–
converts glucose in blood into glycogen to
be stored in the liver & muscles
HYPOSECRETION- of insulin causes diabetes
mellitus. – in this disease liver & muscles
cells –unable to convert glucose to glycogen –level
of glucose in blood rises – also called as
HYPERSECRETION – increased secretion
of insulin leads to hypoglycemia or decreased
level of glucose – symptoms –
weakness,tremor
DELTA CELLS-
secrete SOMATOSTATIN-
Inhibhits secretion of
pancreatic hormones

36. GONADS – MALE / FEMALE

37. MALE & FEMALE GONADS

38. MALE GONADS FEMALE GONADS

39. FEMALES - A pair of ovaries is
present in the abdomen.
MALES - A pair of testes is present
in the abdomen.
GONADS
REPRODUCTIVE GLANDS
LOCATION
FUNCTION
OVARIES – ESTROGENS &
PROGESTERONE Hormone –
predominant in female -
stimulates development of female
secondary sex characteristics,
play a role during menstruation &
pregnancy
prepare the body for child birth.
TESTES- TESTOSTERONE Hormone –
Predominant in males
stimulates development of male secondary
sex characteristics,
increase in height,
maintaining sex drive,
maintaining health level of muscle &
bone mass
sperm productionPLACENTA – Temporary gland
promotes progesterone synthesis during pregnancy
Inhibits immune response against the fetus

40. YOGIC CO-RELATION
• YAM/NIYAM -
 Observing these have positive and calming effect on mind.
 Gives emotional stability and harmony .
 All these have a positive effect on the Endocrine System through the influence on the
Hypothalamus
• TRATAK & OM CHANTING -
 Increases the parasympathetic tone on body .
 Regulation of hormones & helpful towards maintenance of Homeostasis

41. ASANAS
• Asanas balance the hormonal secretions from the various glands .
• The twisting & bending positions of the asana, held for specific, continued time
period places specific pressure on various glands, thus stimulating them in various
ways (- bend , stretch , pressure ) and regulating their secretions.
• Inverted Asanas e.g Shirshasan , Sarvangasan increase blood flow to the brain,thus
having a positive effect on hypothalamus , pituitary & pineal glands.
• Sarvangasan , Matsyasan ,Halasan – thyroid /parathyroid .
• Ardhamatsyendrasan stimulates the pancreas , effective in the optimum release of
insulin & glycogen , thus regulating sugar levels
• Core strengthening Asanas like Dronasan , Bhujangasan , Mayurasan , Dhanurasan
etc influence the adrenals & pancreas.

42. PRANAYAMA-
• Has a very good effect on Endocrine System
• During pranayama practice there is a better absorption of oxygen in each cell
of the body .
• Blood supply , oxygen supply , flow of unobstructed prana also increases to
the brain & hypothalamus thereby improving their functioning capacity.
• Hypothalamus being the seat of emotions – stress & emotions are better
controlled .

43. PRANAYAMA …contd
• Pranayama improves the relationship between the hypothalamus –
pituitary and the other glands
• thus the entire endocrine system is balanced.
• Pranayama regularizes the flow of prana through the naadis.
• Now, flow of prana has a direct relationship to various body
functions.
• It has a relation to the Nervous system & also in improved flow of
nerve impulses.
• Further, Endocrine system functioning is closely related to Nervous
system functioning .
• All these lead to regularization of the Endocrine System.

44. MUDRAS and BANDHAS
• These are the higher practices in Hathayog specifically targeting the
Endocrines for progress in spiritual journey.
• As these influence the endocrine glands directly , it follows that they have
great impact on the Chakras – relevant to the subtle body & thus helping to
Kundalini Shakti awakening .
• Brahma/Dutta Mudra - thyroid & parathyroid
• Simha Mudra – again thyroid & para thyroid
• Viparit Karni Mudra – regulation of female reproductive organs – Ovaries

45. • Tadagi Mudra, Yog Mudra – pancreas ,adrenals
• Moolbandh- Gonads
• Jalandar Bandha- thyroid , parathyroid .Also thymus
• Uddiyan bandh- Adrenals , pancreas.
Regular practice of Bahirang Yog -Kriyas ,Asan , Mudras , Bandhas &
Pranayam help to maintain optimum functioning capacity of of the
Endocrine glands… thus both physical & mental health balanced
and facilitates the maintenance of Homeostasis in the body

46. • Antarang Sadhana : establishes harmony at the chitta level which
then percolates to all the levels.Harmony at the brain level leads
to stabilizing harmonious function of the neuro-endocrine axis.
• Bhakti Yog practices lead to emotional catharsis & emotional
culturing. Since extreme emotions are removed , they no longer
adversely influence the hypothalamus .So pituitary functions ae
also not disturbed.
CONCLUSION : All yogic practices influence the endocrine system in
a positive way, thereby leading to a balance , harmony and
integration at all levels. Thus Homeostasis is maintained within the
body with all Systems functioning at optimum leading to an overall
well developed personality , general well- being & good health