Animals rely on two systems for regulation:
Nervous System is a system of nerve cells called neurons. It
consists of a central nervous system (brain and spinal cord)
and peripheral nerves. Typical responses are fast and short
lasting.
Endocrine System is a system of ductless glands that secrete
hormone into the blood. Hormones travel to target tissues.
Typical responses are slow and long lasting.
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Progesterone
Estradiol
2003-2004
Human Endocrine
Glands
Ductless glands
transport hormones in
the blood
Duct glands are
exocrine glands that
use tubes to carry the
secretion
(salivary, tears)
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2003-2004
Pituitary gland and Hypothalamus serve to link the nervous
system other glands and metabolic functions.
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2003-2004
Mechanisms
of hormone
release
(a) Humoral: in response to changing
levels of ions or nutrients in the blood
(b) Neural: stimulation by nerves
(c) Hormonal: stimulation received from
other hormones
4
Learn the 3 endocrine organs on this slide:
Hypothalamus
Pituitary (hyophysis)
Pineal
Hypothalamus__
Anterior pituitary__
(adenohypophysis)
_____________Posterior pituitary
(neurohypophysis)
Hypothalamus___________
Pituitary__________
(hypophysis)
5
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2003-2004
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2003-2004
Thyroid and Parathyroid help regulate calcium
metabolism
Feedback!
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2003-2004
Pancreas helps regulate blood glucose
feedback
Insulin from Beta cells reduce blood sugar
Glucagon
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Biologyfrom Alpha cells increase blood sugar
2003-2004
feedback
Female sex traits
include the
menstrual cycle and
the changes seen
during puberty
LH and FSH from
the pituitary
Estrogen and
progesterone from
the ovary
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2003-2004
Identify the Glands
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2003-2004
Disorders of the Endocrine
System
• Acromegaly
– An enlargement of the bones of the hands, feet,
and jaws
• Addison's disease
– Caused by hyposecretion of the hormones
produced by the cortex of the adrenal gland
• Cretinism
– Condition resulting from a congenital deficiency of
thyroid secretion or hypothyroidism
Disorders of the Endocrine
System (continued)
• Cushing’s syndrome
– Disorder that causes hyperactivity of the adrenal
glands, which is triggered by the oversecretion of
the pituitary hormone ACTH
• Diabetes insipidus
– From an acquired or inherited decrease in the
antidiuretic hormone secreted by the pituitary
• Diabetes mellitus
– A disorder of carbohydrate, fat, and protein
metabolism resulting from insufficient insulin
production by the pancreas
Disorders of the Endocrine
System (continued)
• Dwarfism
– Results from hyposecretion of the growth
hormone of the pituitary gland, which has been
caused by a tumor, infection, genetic factors, or
trauma
• Gigantism
– An excessive growth of the long bones caused by
hypersecretion of the somatotropic hormone
• Graves’ disease
– Caused by hyperthyroidism or thyrotoxicosis
Disorders of the Endocrine
System (continued)
• Hyperparathyroidism
– Causes hypercalcemia, an increased calcium blood
level
• Hypoglycemia
– Results from increased insulin production by the
pancreas
• Hypoparathyroidism
– A decreased secretion of parathyroid hormone
that causes tetany
Disorders of the Endocrine
System (continued)
• Hypothyroidism
– Also called Hashimoto's disease, results from an
insufficient production of thyroxine
• Syndrome of inappropriate antidiuretic
hormone (SIAD)
– Involves water intoxication and the dilution of
intracellular and extracellular body tissues, usually
resulting from lung cancer
• Virilism
– Results from increased secretion in the adrenal
glands
Pathology, continued
 Adrenal gland
 Cushing’s syndrome (see next pic)
 Usually caused by an ACTH-secreting pituitary
tumor
 Rarely by tumor of adrenal cortex
 Iatrogenic
 Addison’s disease
 Hyposecretion (under secretion) of adrenal cortex
 Usually involves cortisol and aldosterone: low
blood glucose and sodium, severe dehydration,
fatigue, loss of appetetie, abdominal pain
(Jane Austin)
17
Thyroxin – increases metabolic rate
Overactive
• Goitre
• Hyperthyroidism
• Grave’s Disease
Underactive
• Goitre
• Hypothyroidism
• Hashimoto’s Disease
• Myxoedema (adults)
• Cretinism (kids)
Calcitonin – Inc. Ca uptake by
bones and dec. Ca level in blood
Overactive
• Tetany
Underactive
• Kidney Stones
• Osteoporosis
Parathormone (PTH) – inc. Ca
level in blood, dec. Ca level in bone
Overactive
• Kidney Stones
• Osteoporosis
Underactive
• Tetany
Insulin – dec. blood sugar levels
Overactive
• Hypoglycemia
• Hyperinsulinism
(insulin shock)
Underactive
• Hyperglycemia
• Diabetes
Myxoedema
•
•
•
•
•
•
Puffiness (swelling)
Fatigue
Obesity
Dry, thickened skin
Mental impairment
Thin, brittle hair
Cretinism
• Results from thyroid hormone
insufficiency in infancy
•
•
•
•
Protuberant abdomen
Short Stature
Infertility
Neurological
impairment
• Constant Fatigue
• Obesity
ENDOCRINE DISORDERS
2 Categories:
• Abnormal hormone production
• Abnormal cellular sensitivity
ACROMEGALY:
• Over production of growth
hormone after the epiphyseal
plates have fused
• Bone shape changes
• Cartilaginous areas of skeleton
enlarge
• Broad facial features
• Enlarged lower jaw
Endocrine System…. Professor KS Satyapal
20
ENDOCRINE DISORDERS
GOITER
• Enlarged thyroid gland
• Results from thyroid hormone
hyposecretion
• Due to iodine insufficiency
Endocrine System…. Professor KS Satyapal
22
Goiter: Iodine deficiency and feedback causes the thyroid to
enlarge
This people have a goiter, a condition
that is easily preventable with iodized
salt
•Results from thyroid hormone
hyposecretion
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•Due to iodine insufficiency