• enhance transport of blood glucose into cells
• decrease concentration of blood glucose
• raise energy storage

1. glucose transported into GLUT2
2. glucose metabolized
3. produces ATP and ATP will close the potassium channels, leading to depolarization
4. this will open voltage gated calcium channels, leading to calcium influx
5. leads to exocytosis of insulin granules

• blood glucose
• GI hormones
• blood AA's
• parasympathetic system
• sympathetic system (inhibitory)

All the others are stimulatory.

1. insulin bind to receptor on cell surface
2. leads to phosphorylation cascade, leading to enzyme activation or inhibition
3. translocation of glucose transporter (GLUT4) to the cell surface in vessicle

• increase glucose uptake into cells
• increase glycogen formation
• decrease glycogenolysis
• decrease gluconeogenesis
• increase protein synthesis (decrease AA's)
• increase fat deposition (decrease fatty acids)
• decreases lipolysis (decrease ketoacids)
• decrease potassium uptake (hypokalemia)

• intense thirst (polydypsia)
• glycosuria
• inccrease urine volume
• fasting plasma glucose above normal
• glucose plasma rises more after glucose load and stays high

• deficiency in insulin
• caused by autoimmune destruction of islet beta cells

• symptoms of hyperglycemia
  • polyuria
  • glycosuria
  • polydipsia
  • dehydration
• symptoms of starvation
  • weight loss
  • wasting
  • weakness
• symptoms of ketoacidosis
  • lipolysis increase, leads to increase free fatty acids, causin ketoacidosis

• due to fatty acids
  • atherosclerosis (ischemia)
  • microvascular disease
    • nephropathy
    • retinopathy
    • peripheral neuropathy

• muscular
  • weakness
  • atrophy
  • ataxic gut
• sensory
  • pain
  • paresthesia
  • numbness
  • paralysis
  • cramping
  • falls

• diet
  • avoid rapidly absorbed carbs
  • control caloric intake to control weight
  • low fat diet reduce atheroschlerosis
• diet and oral hypoglycemic medication (type II treatment)
• diet and insulin (type I and II treatment)
  • insulin administered via subcutaneous injections
    • inactivated in GI if taken orally

• increase insulin secretion (sulfonylureas, meglitinides)
• decrease starch digestion (glucosidases inhibitors)
• increase glucose uptake (Metformin, thiazolidinediones)
• decrease glucose production (see above)

• regular
  • peaks at 2-4 hours
  • duration of 5-8 hours
• intermediate acting/lente
  • peak at 6-14 hours
  • duration of 20 or more hours

• due to raised epinepherine and low cerebral glucose (brain use 50% of glucose from liver)
  • headache
  • drowsiness
  • impaired speech
  • tachycardia
  • trembling
  • coma (IF SEVERE)

• cause- too much insulin
• treatment
  • glucose inake
  • glucagon pens for intramuscular injection

low blood glucose

high AA concentration

exercise

• increase gluconeogenesis
• increase glycogenolysis
• increase insulin secretion
• increase lipolysis (increase fatty acids in blood)
• increase ketoacid formation (increase ketoacids in blood)

• epinepherine (inhibit insulin secretion)- respond to stress
• cortisol (reduce insulin sensitivity)- respond to stress
• growth hormone (reduce insulin sensitivity)
• thyroid hormone (also enhance GI absorption)- BUT ONLY IN HIGH DOSES

Stimulate glycogenolysis and gluconeogenesis

• spermatogenesis (seminiferous tubules)
• testosterone production (Leydig cells)

• support spermatogenesis
  • androgen binding
  • removing waste
  • blood testis barrier

• LH stimulates Leydig cells to produce testosterone (has paracrine effect on Sertoli cells)
  • testosterone negatively feeds back on LH and GnRH (not FSH)
• FSH stimulates Sertoli cells
  • enhances spermatogenesis
  • sertoli cells produce inhibin, which negatively feeds back on FSH

• cholesterol to pregnenolon
• pregnenolone to 17-OH pregnenolone via 17 alpha hydroxylase
• 17 OH pregnenolon to DHEA
• DHEA to androstenedione
• androstenedione to testosterone via 17 beta hydroxylase (dehydrogenase)

• DHEA
• androstenedione
• DHT
• estradiol (small amount converted from testosterone)

Remember, 5% of androgens secreted by adrenal cortex.

• upon puberty, hypothalamus secretes 8-10 pulses of GnRH per day following puberty
• pulse amplitude and frequency can be momdulated
• pituitary gonadotrophs release FSH and LH

• low during prepuberty
• highest during puberty
• slight decrease during adulthood

• growth of male reproductive tract (penis, seminal vesicles)
• increase libido
• negative feedback on pituitary
• development of muscle
• deepen voice
• stimulates spermatogenesis
• pubertal growth spurt and fusion of growth plates of long bones

• fetal differentiation of penis, scrotum, and prostate
• male hair pattern and baldness
• sebaceous gland activity
• prostate gland

1. testosterone/DHT diffuse into cell
2. binds to androgen receptor protein
3. androgen receptor complex moves into nucleus where it initates gene transcription
4. new mRNA generated and translated into new proteins that produce physiologic actions