PITUITARY GLANDPITUITARY GLAND

considered the master gland because it considered the master gland because it controls all of the endocrine glands controls all of the endocrine glands

throughout the body; it is located in throughout the body; it is located in the brain next to the hypothalamus the brain next to the hypothalamus (considered part of the nervous system and (considered part of the nervous system and endocrine system). It has two distinct endocrine system). It has two distinct lobes:lobes:

i) Posterior Lobei) Posterior Lobe: :

stores and releases hormones stores and releases hormones produced by the hypothalamus:produced by the hypothalamus:

1. 1. Antidiuretic Hormone (ADH)Antidiuretic Hormone (ADH): stimulates the : stimulates the kidney to become more permeable to water, kidney to become more permeable to water, conserves body water, less urine producedconserves body water, less urine produced– HyposecretionHyposecretion: Diabetes Insipidus: Diabetes Insipidus– HypersecretionHypersecretion: excessive water retention: excessive water retention

2. 2. OxytocinOxytocin: stimulates the contraction of the : stimulates the contraction of the uterus during labor and mammary glands for milk uterus during labor and mammary glands for milk secretetion.secretetion.

ii) Anterior Lobeii) Anterior Lobe::

produces the following hormonesproduces the following hormones

1. Growth Hormone (GH):1. Growth Hormone (GH):

stimulates the general growth of bones, stimulates the general growth of bones, muscles and organs by increasing the muscles and organs by increasing the uptake of amino acids, the metabolism of uptake of amino acids, the metabolism of fats, and rate of cell division.fats, and rate of cell division.

HyposecretionHyposecretion in children causes in children causes DwarfismDwarfism

Hypersecretion Hypersecretion in children causes in children causes Giantism and in adults AcromegalyGiantism and in adults Acromegaly

2. Prolactin: 2. Prolactin:

stimulates milk production and secretionstimulates milk production and secretion HyposecretionHyposecretion results in poor milk results in poor milk

productionproduction HypersecretionHypersecretion causes overproduction of causes overproduction of

milkmilk

3.Follicle Stimulating Hormone 3.Follicle Stimulating Hormone (FSH): (FSH):

stimulates ovarian follicle(egg) stimulates ovarian follicle(egg) development and spermatogenesis; also development and spermatogenesis; also stimulates production of Estrogen by the stimulates production of Estrogen by the ovaries.ovaries.

HyposecretionHyposecretion no follicle and sperm no follicle and sperm development,low estrogen in femalesdevelopment,low estrogen in females

HypersecretionHypersecretion ; multiple follicle ; multiple follicle development, high sperm countdevelopment, high sperm count

4. Lutenizing Hormone (LH): 4. Lutenizing Hormone (LH):

stimulates ovulation and the production of stimulates ovulation and the production of progesterone by the corpus luteum in the progesterone by the corpus luteum in the female; in the male stimulates the interstitial female; in the male stimulates the interstitial cells to produce testosteronecells to produce testosterone

Hyposecretion: Hyposecretion: no ovulation, low no ovulation, low progesterone and testosterone levelsprogesterone and testosterone levels

HypersecretionHypersecretion:high levels of progesterone :high levels of progesterone and testosteroneand testosterone

5. Thyroid Stimulating Hormone 5. Thyroid Stimulating Hormone (TSH): (TSH):

stimulates the thyroid gland to release its stimulates the thyroid gland to release its hormoneshormones

HyposecretionHyposecretion: low thyroxin levels: low thyroxin levels HypersecretionHypersecretion: high thyroxin levels: high thyroxin levels

6. Adrenocorticotropic Hormone 6. Adrenocorticotropic Hormone (ACTH): (ACTH):

stimulates the adrenal cortex to release its stimulates the adrenal cortex to release its hormones.hormones.

HyposecretionHyposecretion: low Cortisol and : low Cortisol and aldosterone levelsaldosterone levels

HypersecretionHypersecretion: High Cortisol and : High Cortisol and aldosterone levelsaldosterone levels

7. Melanocyte Stimulating 7. Melanocyte Stimulating Hormone (MSH): Hormone (MSH):

stimulates the melanocytes in the skin to stimulates the melanocytes in the skin to produce melanin; pigmentation in the skin, produce melanin; pigmentation in the skin, in response to UV exposure.in response to UV exposure.

HyposecretionHyposecretion: low pigmentation: low pigmentation HypersecretionHypersecretion: dark pigmentation: dark pigmentation

THYROID GLANDTHYROID GLAND: :

located in the neck, below the larynx; located in the neck, below the larynx; controlled by TSH secreted by the pituitary controlled by TSH secreted by the pituitary and it is also affected by levels of Iodine in and it is also affected by levels of Iodine in the body.the body.

Secretes two main hormones:Secretes two main hormones:

1.1. Thyroxin Thyroxin: : regulates cell metabolism by speeding up the rate regulates cell metabolism by speeding up the rate

of cell respiration and the utilization of glucose of cell respiration and the utilization of glucose and oxygen.and oxygen.

HyposecretionHyposecretion: low metabolism, Cretenism in: low metabolism, Cretenism inchildren, Myxedema in Adultschildren, Myxedema in Adults

HypersecretionHypersecretion: increases metabolic rate, : increases metabolic rate, Grave’s Disease.Grave’s Disease.

Note: Iodine must be present to make thyroxin; Note: Iodine must be present to make thyroxin; this is why salt is iodized to prevent the disorder this is why salt is iodized to prevent the disorder GoitreGoitre

2. 2. Calcitonin: Calcitonin:

reduces the amount of calcium in the blood reduces the amount of calcium in the blood by stimulating the bones to inhibit calcium by stimulating the bones to inhibit calcium release.release.

HyposecretionHyposecretion: increased Ca2+ levels in : increased Ca2+ levels in bloodblood

HypersecretionHypersecretion: decreases Ca2+ levels: decreases Ca2+ levels

PARATHYROID GLANDSPARATHYROID GLANDS: :

the four smallest glands in the body found the four smallest glands in the body found imbedded in the tissues of the Thyroid gland. imbedded in the tissues of the Thyroid gland. Secrete one hormone:Secrete one hormone:

Parathyroid Hormone (PTH)Parathyroid Hormone (PTH): raise blood : raise blood calcium levels by stimulating the release of calcium levels by stimulating the release of Ca2+from the bones and promoting Ca2+ uptake Ca2+from the bones and promoting Ca2+ uptake from the kidneys.from the kidneys.

HyposecretionHyposecretion: decreases Ca2+ levels: decreases Ca2+ levels HypersecretionHypersecretion: increased Ca2+ levels: increased Ca2+ levels

PANCREASPANCREAS: :

located below the stomach and is located below the stomach and is considered both an exo and an endocrine considered both an exo and an endocrine gland.gland.

Contains specialized cells known as the Contains specialized cells known as the Islets of Langerhans which secrete the Islets of Langerhans which secrete the following hormones:following hormones:

1. 1. InsulinInsulin: :

decrease blood glucose levels bydecrease blood glucose levels bystimulating the conversion of glucose to stimulating the conversion of glucose to glucagon in the liver, increasing cell glucagon in the liver, increasing cell metabolism of glucose and making cells metabolism of glucose and making cells permeable to glucosepermeable to glucose

HyposecretionHyposecretion: Diabetes Mellitus: Diabetes Mellitus HypersecretionHypersecretion: low blood glucose levels : low blood glucose levels

(Hypoglycemia); insulin shock(Hypoglycemia); insulin shock

2. 2. GlucagonGlucagon: :

increases blood glucose levels by increases blood glucose levels by stimulating the breakdown of stimulating the breakdown of

glycogen to glucose in the liver and glycogen to glucose in the liver and muscles.muscles.

HyposecretionHyposecretion: low glucose levels : low glucose levels (Hypoglycemia)(Hypoglycemia)

HypersecretionHypersecretion: raised glucose levels : raised glucose levels (Hyperglycemia)(Hyperglycemia)

ADRENAL GLANDSADRENAL GLANDS: :

located above the kidneys; prepares body located above the kidneys; prepares body for stress, aid in the regulation of the for stress, aid in the regulation of the mineral content of the blood and in the mineral content of the blood and in the production of some sex hormones. Has two production of some sex hormones. Has two distinct parts:distinct parts:

i) Adrenal Cortex: i) Adrenal Cortex:

the outer portion of the gland; stimulated by the outer portion of the gland; stimulated by ACTH from the anterior pituitary. Produces:ACTH from the anterior pituitary. Produces:

1.1.CortisolCortisol: a glucocorticoid that increases the : a glucocorticoid that increases the levels of amino acids in the blood; which are levels of amino acids in the blood; which are converted into glucose therefore increasing converted into glucose therefore increasing blood sugar levels.blood sugar levels.

HyposecretionHyposecretion: Low glucose levels: Low glucose levels HypersecretionHypersecretion: high glucose levels: high glucose levels

2. Aldosterone:2. Aldosterone:

increases the movement of Naincreases the movement of Na++and water and water out of the kidney and into the blood, in out of the kidney and into the blood, in response to low blood pressure.response to low blood pressure.

HyposecretionHyposecretion: low blood Na+, high: low blood Na+, highvolumes of urinevolumes of urine

HypersecretionHypersecretion: High blood Na+, low: High blood Na+, lowvolumes of urine.volumes of urine.

3. Sex Steroids:3. Sex Steroids:

produces a small amount of estrogen, produces a small amount of estrogen, progesterone and testosterone for use when progesterone and testosterone for use when the sex organs are non-functionalthe sex organs are non-functional

This is why both males and females have all This is why both males and females have all sex hormones present in their body.sex hormones present in their body.

ii) Adrenal Medullaii) Adrenal Medulla::

interior portion of the gland; its secretions interior portion of the gland; its secretions work closely with the nervous system to work closely with the nervous system to help in stress responses:help in stress responses:

1. 1. AdrenalinAdrenalin: :

increases blood sugar levels by stimulating increases blood sugar levels by stimulating the conversion of glycogen to glucose, the conversion of glycogen to glucose, constricts blood vessels in skin, increases constricts blood vessels in skin, increases blood pressure, heart rate and breathing blood pressure, heart rate and breathing rate.rate.

HyposecretionHyposecretion: inadequate response to : inadequate response to stressstress

HypersecretionHypersecretion: overreaction to stress.: overreaction to stress.

2. 2. NoradrenalinNoradrenalin: :

has effects similar but not as strong as has effects similar but not as strong as adrenalin; it helps control blood pressure.adrenalin; it helps control blood pressure.

TESTESTESTES: :

the male gonads; produces the male sex the male gonads; produces the male sex hormone hormone TestosteroneTestosterone

it stimulates spermatogenesis, development it stimulates spermatogenesis, development and maintenance of the secondary male sex and maintenance of the secondary male sex characteristics.characteristics.

HyposecretionHyposecretion: low sperm production, : low sperm production, inhibited sexual maturationinhibited sexual maturation

HypersecretionHypersecretion: increases sperm : increases sperm production, production,

OVARIES: OVARIES:

the female gonads; produces the two the female gonads; produces the two female sex hormones: female sex hormones:

1. 1. EstrogenEstrogen: :

responsible for the development and responsible for the development and maintenance of the secondary sex maintenance of the secondary sex characteristics. Promotes development of the characteristics. Promotes development of the endometrium lining; prevents ovulation after endometrium lining; prevents ovulation after fertilization; directly regulated by FSH.fertilization; directly regulated by FSH.

HyposecretionHyposecretion: underdevlopment of sex : underdevlopment of sex characteristics; inhibited menstruationcharacteristics; inhibited menstruation

HypersecretionHypersecretion: early puberty: early puberty

2. 2. ProgesteroneProgesterone: :

maintains the endometrium ,maintains the endometrium ,inhibits uterine contractions and ovulation; inhibits uterine contractions and ovulation; directly regulated by LH.directly regulated by LH.

HyposecretionHyposecretion: early menstruation, no : early menstruation, no maintence of endometrium maintence of endometrium

HypersecretionHypersecretion: no menstruation: no menstruation

PLACENTAPLACENTA: :

an organ formed during pregnancy; an organ formed during pregnancy; provides for connection between mother and provides for connection between mother and child for exchange of wastes, nutrients and child for exchange of wastes, nutrients and gases. Producesgases. Produces

1. 1. RelaxinRelaxin: relaxes the pelvic ligaments : relaxes the pelvic ligaments widening the birth canal.widening the birth canal.

2.2. Estogen and ProgesteroneEstogen and Progesterone: used to : used to maintain the endometrium lining during maintain the endometrium lining during pregnancy and prevents further ovulationpregnancy and prevents further ovulation