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Chapter 20 Lecture and Animation Outline To run the animations you must be in Slideshow View. Use the buttons on the animation to play, pause, and turn audio/text on or off. Please Note: Once you have used any of the animation functions (such as Play or Pause), you must first click on the slide’s background before you can advance to the next slide.
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20.1 Overview of the Endocrine System • The endocrine system consists of glands and tissues that secrete hormones. • Hormones are chemicals that affect other glands or tissues, located far away from the sites of hormone production. • Like the nervous system, the endocrine system influences other organ systems in maintaining homeostasis. – Influence on cellular metabolism, growth and development 2
20.1 Overview of the Endocrine System • Growth factors – hormones that promote cell division and mitosis • Local hormones – not carried by the blood – Affect tissues locally – Ex: prostaglandins
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20.1 Overview of the Endocrine System • Endocrine glands – Have no ducts – Secrete hormones into tissue fluid – Hormones diffuse into the bloodstream
• Exocrine glands – Secrete their products through ducts • Ex: salivary glands send saliva to the mouth through salivary ducts
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Hormones and Homeostasis • Homeostasis requires cooperation between the endocrine and nervous systems. Endocrine System
Nervous System
Secretes hormones into the blood
Transmits nerve impulses
Slower response
Faster response
More prolonged response
Less prolonged response
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Hormones and Homeostasis • The blood concentration of a substance prompts an endocrine gland to secrete its hormones. – Ex: The parathyroid gland secretes a hormone when blood Ca+2 level falls below normal. – Osteoclasts respond to hormone by slowly releasing Ca+2 from bone. – It take time for the response, but it is long-lasting.
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The Endocrine System Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
pineal gland hypothalamus pituitary gland (hypophysis)
thyroid gland
thymus gland parathyroid glands (posterior surface o f thyroid)
adrenal glands
pancreas
ovary (female) testis (male)
Figure 20.1
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Hormones and Homeostasis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
• Production of most hormones controlled by two things
Control center
response to stimulus
data to control center
Sensor
Effect
– Negative feedback • Sensitive to either the condition it regulates or the blood level of the hormone it is producing
change of internal conditions
negative feedback and return to normal
stimulus
– Action of other hormones
Homeostasis
• Insulin and glucagon
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Hormones and Homeostasis • Example of negative feedback – As the blood glucose level rises, the pancreas secretes insulin. – Insulin causes the liver to store glucose, and glucose is removed from the blood. – The stimulus for insulin production is, thereby, inhibited. – The pancreas stops secreting insulin.
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Hormones and Homeostasis • Hormone regulation by release of an antagonistic hormone – The effect of insulin is offset by the secretion of glucagon. – Insulin lowers the blood sugar level, while glucagon raises it.
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The Action of Hormones • Hormones act on target cells. – May increase uptake of a substance – May bring about alteration of structure of target cell
• Hormones fall into two chemical classes. – Peptide hormones – peptides, proteins, glycoproteins or modified amino acids – Steroid hormones – same complex of four rings, but varying side chains
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The Action of Hormones • Hormones function as chemical signals. – Chemical signals - a means of communication between cells, body parts, or even individuals • Typically affect the metabolism of target cells with appropriate receptors – For peptide hormones, receptors on cell surface – For steroid hormones, receptors inside cell (cytoplasm or nucleus)
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
nontarget cell receptors
hormone
capillary
target cells
Figure 20.2
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The Action of Hormones • The peptide hormone initiates a chemical signaling process after binding to its receptor; it serves as the first messenger. • The activated receptor leads to the production of a second messenger, (cAMP is most common). • The 2nd messenger sets in motion an enzymatic cascade. • Each enzyme, in turn, activates another enzyme. • During each step in the cascade, more reactions occur (1000-fold response possible).
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Peptide Hormone Action
capillary
1. Epinephrine binds to a receptor in the plasma membrane. epinephrine (first messenger)
activated enzyme
receptor protein
2. Binding leads to activation of an enzyme that changes ATP to cAMP.
plasma membrane
cAMP (second messenger)
ATP
3. cAMP activates an enzyme cascade.
4. Many molecules of glycogen are broken down to glucose, which enters the bloodstream.
Figure 20.3
glucose (leaves cell and goes to blood)
glycogen
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The Action of Hormones • The steroid hormone has an alternate way because it can diffuse through the target cell membrane. • The hormone can bind to its receptor either in the cytoplasm or nucleus. • The hormone receptor complex then binds to DNA to activate transcription of a certain gene into mRNA. • mRNA translation results in enzymes or other proteins that can carry out a response to the hormone. 19
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Steroid Hormone Action
steroid hormone
1. Hormone diffuses through plasma membrane because it is lipid soluble.
plasma membrane
cytoplasm
nucleus 2. Hormone binds to receptor inside nucleus.
protein DNA
receptor protein mRNA
3. Hormone-receptor complex activates gene and synthesis of a specific mRNA molecule.
ribosome
mRNA
4. mRNA moves to ribosomes, and protein synthesis occurs.
Figure 20.4
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Pheromones • Pheromones are chemical signals that act between individuals of the same species. – Effects better known in animals other than humans • Ex: female moths release an attractant that acts on male moths even miles away
– Humans do produce pheromones • Airborne chemicals released by scalp, oral cavity, axilla, genital areas • Possibly plays role in mate attraction • Axillary secretions can affect the menstrual cycle 21
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20.2 Hypothalamus and Pituitary Gland • The hypothalamus regulates the internal environment in two ways. – Through the autonomic nervous system • Heartbeat, blood pressure, appetite, body temperature, water balance
– Through control of pituitary gland secretions • Posterior pituitary • Anterior pituitary
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Posterior Pituitary • Neurons in the hypothalamus called neurosecretory cells produce antidiuretic hormone (ADH) and oxytocin. – Hormones travel down axons and are stored in axon terminals in the posterior pituitary.
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Posterior Pituitary • ADH - Antidiuretic hormone – Released from posterior pituitary in response to increased concentration of blood (not enough water) – Causes increased reabsorption of water in the kidneys • As water reabsorption occurs, the blood concentration becomes normal and ADH is shut off.
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Posterior Pituitary • Oxytocin – Causes uterine contractions and milk letdown during lactation – Neurological impulses from pressure and irritation of uterus causes oxytocin release • Oxytocin causes contractions which causes more pressure and irritation more oxytocin more contractions – An example of positive feedback
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Anterior Pituitary • A portal system, consisting of two capillary networks connected by a vein, lies between the hypothalamus and the anterior pituitary. – Hypothalamus controls the anterior pituitary by producing • Hypothalamic-releasing hormones – Stimulates the anterior pituitary gland to release certain hormones
• Hypothalamic-inhibiting hormones – Prevents the secretion of certain hormones
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Anterior Pituitary • Three anterior pituitary hormones have target effects on other glands. – Thyroid-stimulating hormone (TSH) stimulates the thyroid gland to produce thyroid hormones. – Adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex to produce glucocorticoids. – Gonadotrophic hormones (FSH and LH) stimulate the gonads to produce estrogen and testosterone.
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20.2 Hypothalamus and Pituitary Gland Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
• Anterior Pituitary
hypothalamus
– In each instance, the releasing hormone (hormone 1) blood level of the last hormone in the anterior pituitary hypothalamus-anterior pituitary-target gland stimulating hormone (hormone 2) control system exerts negative feedback over target gland secretions of the first target gland hormone two structures.
feedback inhibits release of hormone 1
feedback inhibits release of hormone 2
(hormone 3)
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Anterior Pituitary • Three anterior pituitary hormones do not affect other glands. – Prolactin (PRL) stimulates the mammary glands to synthesize milk. – Melanocyte-stimulating hormone (MSH) stimulates the pigment-producing melanocytes of the skin. – Growth hormone (GH) stimulates bone and muscle growth and increases protein synthesis and fat metabolism. 29
Hypothalamus and the Pituitary Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
hypothalamus
1. Neurosecretory cells produce hypothalamic- releasing and hypothalamic-inhibiting hormones.
2. These hormones are secreted into a portal system.
1. Neurosecretory cells produce ADH and oxytocin. optic chiasma
3. Each type of hypothalamic hormone either stimulates or inhibits production and secretion of an anterior pituitary hormone.
2. These hormones move down axons to axon endings. portal system 3. When appropriate, ADH and oxytocin are secreted from axon endings into the bloodstream.
Posterior pituitary
Figure 20.5
Kidney tubules: antidiuretic hormone (ADH)
Smooth muscle in uterus: oxytocin
Mammary glands: oxytocin
Anterior pituitary
Mammary glands: pr olactin (PRL)
4. The anterior pituitary secretes its hormones into the bloodstream, which then delivers them to specific cells, tissues, and glands.
Thyroid: thyroid-stimulating hormone (TSH)
Adrenal cortex: adrenocorticotropic hormone (ACTH)
Bones, tissues: growth hormone (GH)
Ovaries, testes: gonadotropic hormones (FSH, LH)
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20.3 Thyroid and Parathyroid Glands • The thyroid gland is a large gland located in the neck. – Attached to the trachea just below larynx
• The parathyroid glands are embedded in the posterior surface of the thyroid gland.
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Thyroid Gland • Thyroid gland has many follicles, each a small spherical structure of thyroid cells that produce – Triiodothyronine (T3) (three iodine atoms) – Thyroxine (T4) (four iodine atoms)
• Thyroid requires iodine to produce these hormones – Iodine deficiency causes simple goiter
• T3 and T4 increase metabolic rate – Stimulate most body cells to metabolize glucose and utilize more energy 32
Thyroid Gland • Thyroid gland also produces calcitonin – Calcium-regulating hormone – Produced in response to increased blood calcium levels – Causes uptake of calcium by bone • Calcium is important in muscle contraction, nerve conduction, and blood clotting
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Parathyroid Gland • Parathyroid glands produce parathyroid hormone (PTH) – Causes an increase in blood calcium and a decrease in blood phosphate – Increases osteoclast activity and the reabsorption of calcium by the kidneys • Also stimulates activation of vitamin D needed for calcium absorption in the digestive tract
– When blood calcium levels increase, PTH is shut off
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. calcitonin
Regulation of Blood Calcium Level
Thyroid gland secretes calcitonin into blood.
Bones take up Ca2+ from blood.
Blood Ca2+ lowers.
Homeostasis (normal blood Ca2+)
Blood Ca2+ rises.
Parathyroid glands release PTH into blood.
activated vitamin D parathyroid hormone (PTH)
Figure 20.6
Intestines absorb Ca2+ from digestive tract.
Kidneys reabsorb Ca2+ from kidney tubules.
Bones release Ca2+ into blood.
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20.4 Adrenal Glands • The adrenal glands sit atop the kidneys. – Two parts of the adrenal gland that function independently – Adrenal medulla (outer portion) • Under the control of the nervous system
– Adrenal cortex (inner portion) • Under the control of adrenocorticotropic hormone (ACTH), an anterior pituitary hormone
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Adrenal Medulla • The hypothalamus initiates nerve impulses by way of the brain stem, spinal cord, and sympathetic nerves to the adrenal medulla. • The adrenal medulla secretes two hormones – Epinephrine (adrenaline) – Norepinephrine (NE)
• Epinephrine and norepinephrine bring rapid shortterm changes. – Response to stress (fight or flight response) 37
Adrenal Cortex • Hormones of the adrenal cortex result in longterm changes. – Two types of hormones • Glucocorticoids – Regulate carbohydrate, protein, and fat metabolism leading to an increase in blood glucose level
• Mineralocorticoids – Regulate salt and water balance leading to an increases in blood volume and blood pressure
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Adrenal Cortex: Glucocorticoids • Cortisol is the principal glucocorticoid hormone stimulated by ACTH. • Actions – Promotes breakdown of muscle proteins to amino acids • Liver uses amino acids to make glucose
– Promotes metabolism of fatty acids, spares glucose – Overall: Promotes a rise in blood glucose • Beneficial under stress
– Counteracts inflammatory response • Can also suppress the immune system 39
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Adrenal Cortex: Mineralocorticoids • Mineralocorticoid secretion is not controlled by the anterior pituitary. – Aldosterone is the principal mineralocorticoid hormone that targets the kidney. • Increases absorption of Na+, excretion of K+ • Regulates blood volume and pressure • Secretion controlled through release of renin from the kidney
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Adrenal Cortex: Mineralocorticoids • Renin – Released when blood Na+ levels and blood pressure are low – Activates angiotensinogen to angiotensin I – Converts angiotensin I to angiotensin II by enzyme in lung capillaries – Angiotensin II stimulates adrenal cortex to release aldosterone – Effect: Angiotensin II constricts arterioles Aldosterone causes the kidneys to reabsorb sodium. Blood pressure rises. 41
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. atrial natriuretic hormone (ANH)
Regulation of Blood Pressure and Volume
Kidneys excrete Na+ and water in urine.
Heart secretes atrial natriuretic hormone (ANH) into blood.
Blood pressure drops.
Homeostasis (normal blood pressure)
Blood pressure rises.
Kidneys secrete renin into blood.
Kidneys reabsorb Na+ and water from kidney tubules.
renin
angiotensin I and II
aldosterone
Figure 20.8
Adrenal cortex secretes aldosterone into blood.
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Adrenal Cortex: Mineralocorticoids • Atrial natriuretic hormone (ANH) – Produced when atria of the heart are stretched • Represents an increase in blood volume
– Inhibits the release of aldosterone – Results in natriuresis: excretion of Na+ in the urine – Water follows passively so blood volume and therefore pressure decreases
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stress
hypothalamus neurosecretory cells produce hypothalamicreleasing hormone
path of nerve impulses
Stress Response: Long Term Glucocorticoids Protein and fat metabolism instead of glucose breakdown.
neuron cell body anterior pituitary secretes ACTH
Sympathetic Fibers
spinal cord (cross section)
ACTH
epinephrine
Reduction of inflammation; immune cells are suppressed. Mineralocorticoids Sodium ions and water are reabsorbed by kidney.
norepinephrine Stress Response: Short Term
Blood volume and pressure increase.
Heartbeat and blood pressure increase. Blood glucose level rises.
glucocorticoids
Muscles become energized. adrenal medulla
adrenal cortex
mineralocorticoids
Figure 20.7
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20.5 Pancreas • Pancreas is composed of two types of tissue – The exocrine portion secretes digestive enzymes released into the small intestine by ducts. – Pancreatic islets are the endocrine portion of the gland. • Three types of endocrine islet cells
– Alpha cells produce glucagon – Beta cells produce insulin » Regulation of blood glucose levels
– Delta cells produce somatostatin 45
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20.5 Pancreas • Insulin – Released after eating – Stimulates uptake of glucose by cells • Especially muscle, liver, and adipose cells • Decreases blood glucose
• Glucagon – Released before eating when glucose is low – Targets liver and adipose tissue – Increases blood glucose 46
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. insuli n
Regulation of Blood Glucose Level
Liver stores glucose from blood as glycogen. After eating, pancreas secretes insulin into blood. Muscle cells store glycogen and build protein.
Adipose tissue uses glucose from blood to form fat.
Glucose level drops. Homeostasis (normal blood glucose)
Glucose level rises.
Before eating, pancreas secretes glucagon into blood.
Liver breaks Down glycogen to glucose. Glucose enters blood.
Adipose tissue breaks downfat.
Figure 20.9
glucagon
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20.5 Pancreas • Somatostatin – Also known as growth hormone inhibiting hormone – Also produced by cells in the stomach and small intestine – Main effects • Inhibit release of growth hormone by the anterior pituitary • Suppress the release of various hormones produced by the digestive system, including insulin and glucagon 48
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20.6 Other Endocrine Glands • The gonads are the testes in males and the ovaries in females. • The gonads are endocrine glands. • Other glands and certain tissues also produce hormones.
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Testes and Ovaries • Testes – Produce sperm and androgens (e.g., testosterone) – Responsible for male secondary sex characteristics • Beard growth, enlargement of vocal cords and larynx
– Stimulate oil production by oil glands – Involved in pattern baldness – Responsible for increased muscle development
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Testes and Ovaries • Some athletes take supplemental amounts of illegal anabolic steroids. – Include testosterone or related chemicals – Many side effects from taking anabolic steroids • Acne • Body odor • Baldness
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The Side Effects of Anabolic Steroid Use Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
balding in men and women; hair on face and chest in women
'roid mania– delusions and hallucinations; depression upon withdrawal
deepening of voice in women
severe acne
breast enlargement in men and breast reduction in women
high blood cholesterol and atherosclerosis; high blood pressure and damage to heart
liver dysfunction and cancer in women, increased size of ovaries; cessation of ovulation and menstruation
kidney disease and retention of fluids, called "steroid bloat"
stunted growth in adolescents by causing premature ossification of growth plates
reduced testicular size, low sperm count, and impotency
Figure 20.10
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Testes and Ovaries • Ovaries – Produce eggs, estrogen, and progesterone – Estrogen • Stimulates growth of uterus and vagina • Required for egg maturation • Responsible for secondary sex characteristics – Breast development along with progesterone – Fat distribution – Body hair
– Progesterone • Regulation of uterine cycle along with estrogen 53
Thymus and Pineal Glands • Thymus gland – Largest and most active during childhood – Secretes thymosins, hormones involved with maturation of T-lymphocytes
• Pineal gland – Produces melatonin • Involved with sleep/wake cycles and circadian rhythms
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Hormones from Other Tissues • Some organs usually not considered endocrine glands can secrete hormones. • The heart produces natriuretic hormone. • The stomach and small intestine produce hormones that regulate digestive secretions. • Other tissues secrete hormones.
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Leptin • Leptin – Leptin is a protein hormone produced by adipose tissue. – Leptin stimulates the satiety center in the hypothalamus to signal that an individual has had enough to eat. – It is thought that leptin in obese individuals may be ineffective.
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Growth Factors • Growth factors • Stimulate mitosis in tissues • Some released in blood, others act locally
– Granulocyte-macrophage colony-stimulating factor • Produced by many different tissues • Causes bone marrow stem cells to produce granulocytes and macrophages
– Platelet-derived growth factor • Wound healing
– Epidermal growth factor and nerve growth factor • Wound healing 57
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Prostaglandins • Prostaglandins – Produced from arachidonic acid – Act locally; effects depend on location • Muscle contractions in uterus • Mediation of pyrogens’ effects
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20.8 Disorders of the Endocrine System • The endocrine glands play a major role in regulating the development and function of many body systems. • An increase or decrease in production of a hormone can cause significant disease. • Cancer often causes an increase in hormone secretion by affecting the gland. • Various conditions that destroy glands result in decreased secretion of a hormone. 59
Disorders of the Pituitary Gland • Diabetes insipidus (DI) – The posterior pituitary secretes too little ADH. (antidiuretic hormone) • Large amounts of urine are produced, resulting in dehydration.
• Pituitary dwarfism – Too little growth hormone is secreted by the anterior pituitary. • Condition is characterized by small stature but normal proportions. 60
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Disorders of the Pituitary Gland • Gigantism – Excess growth hormone is produced during childhood. – Gigantism also promotes the development of diabetes mellitus.
Figure 20.11
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Disorders of the Pituitary Gland Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Age 9
Age 16
Age 33
Age 52
(all): Reprinted from Clinical Pathologic al Conference, American Journal of Medicine, Vol. 20, page 133, “Acromegaly, Diabetes, Hypermetabolism, Proteinuria and Heart Failure,” copyright 1956, with permission from Elsevier.
• Acromegaly – Excess growth hormone in adulthood – Long bones cannot grow, so the effect is noticeable in the hands, feet, and facial bones Figure 20.12
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Disorders of the Pituitary Gland
Before treatment
Four months after treatment
• Cushing Syndrome – Excess production of ACTH (usually by tumor) – Adrenal cortex then produces excess cortisol • Protein is metabolized, fat is deposited in the midsection Figure 20.13
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Disorders of the Thyroid, Parathyroid and Adrenal Glands • Hypothyroidism – Not enough thyroid hormone is produced. – Failure of thyroid function in infancy or childhood results in congenital hypothyroidism. • Individuals are short and stocky; mental retardation results if treatment does not begin within 1st two months of life
– Treatment consists of the administration of thyroid hormones. 64
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
affected eye
a. Congenital hypothyroidism
b. Simple goiter
c. Exophthalmic goiter
a: © Medical-on-Line/Alamy; b: © Biophoto Associates/Photo Researchers, Inc.; c: © Dr. P. Marazzi/SPL/Photo Researchers, Inc.
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Disorders of the Thyroid, Parathyroid and Adrenal Glands • Hashimoto thyroiditis is a form of hypothyroidism that occurs in adults. – The immune system produces antibodies that destroy the thyroid gland. – Myxedma is a group of clinical symptoms in adults not treated for the condition. • Symptoms include: weight gain, hair loss, constipation or slow heart rate
– Treatment is the administration of thyroid hormones. 66
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Disorders of the Thyroid, Parathyroid and Adrenal Glands Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
• Goiter – Lack of dietary iodine makes the thyroid unable to produce sufficient T3 and T4. – The thyroid gland is consequently constantly stimulated by TSH. – The result is an enlarged thyroid gland. b. Simple goiter
Figure 20.14
© Biophoto Associates/Photo Researchers, Inc.
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Disorders of the Thyroid, Parathyroid and Adrenal Glands • Hyperthyroidism
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
– Results from oversecretion of thyroid hormones • Graves disease arises from antibodies reacting with the TSH receptor, mimicking effect of TSH. – Symptoms include protruding eyes, nervousness, hyperactivity, and abnormal heart rhythms.
affected eye
c. Exophthalmic goiter © Dr. P. Marazzi/SPL/Photo Researchers, Inc.
Figure 20.14
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Disorders of the Thyroid, Parathyroid and Adrenal Glands • Disorders of the parathyroid – Insufficient parathyroid production results in a drop in blood calcium levels. – The body shakes from continuous muscle contraction (tetany).
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Disorders of the Thyroid, Parathyroid and Adrenal Glands • Disorders of the adrenal glands – Addison disease • The most common cause is destruction of the adrenal cortex by the immune system. • Symptoms include weakness, weight loss, abdominal pain, and a bronzing of the skin. • Decreased production of mineral corticoids can affect Na+ and K+ levels, which can adversely affect the heart. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Figure 20.15
a.
b.
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a: © Custom Medical Stock Photo; b: © NMSB/Custom Medical Stock Photos
Diabetes Mellitus • Diabetes mellitus – Affects an estimated 25.8 million Americans, or 8.3% of the population (as of 2010) – Affects ability to regulate glucose metabolism • Type 1 sufferers do not produce enough insulin. • Type 2 sufferers cannot use insulin produced. – As blood glucose rises, glucose and water are lost in the urine – Cells do not take up the glucose – Causes increased thirst, increased hunger • A glucose tolerance test is often used for diagnosis. 71
Glucose Tolerance Test Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
300
Blood Glucose (mg/100 ml)
250
200 renal threshold 150
100
50 diabetic nondiabetic
Figure 20.16
glucose given
1
2
3
Time (hours) 72
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Diabetes Mellitus • Two types of diabetes mellitus – Type 1 – insulin-dependent • Lack of insulin may be due to exposure to environmental agent, such as a virus, or an autoimmune condition. • As cells break down fats for energy, ketones build up in the blood. – Ketoacidosiscomadeath
• Insulin overdose can cause hypoglycemia, unconsciousness – Immediate ingestion of glucose required to counteract
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Diabetes Mellitus • Two types of diabetes mellitus – Type 2 • Insulin-resistant • Linked to obesity - adipose tissue may produce a substance that impairs insulin receptor function • Insulin levels often low - cells may not have sufficient insulin receptors • Controlled by diet, exercise, medications
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Diabetes Mellitus • Diabetics need to monitor their blood sugar several times daily, regardless of which diabetes type they have. • Monitoring is usually done by poking a finger to obtain blood drops to be tested using an external device. • New testing devices are being introduced. • Insulin pumps are replacing the needle and syringe as an injection method. 76
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a.
Figure 20.17
b. (both): Courtesy of Insulet Corporation
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Diabetes Mellitus • Long-term complication of diabetes – Blindness – Kidney disease – Cardiovascular disorders • Can lead to reduced blood flow to limbs (gangrene)
– Diabetic coma in pregnancy (if not managed) • The child has a higher risk of being stillborn or dying shortly after birth.
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