• nervous system- coordinates rapid, precise responses
• endocrine system- controls activities that require longer duration rather than speed

• nervous system- rapid (milliseconds)
• endocrine system- slow (minutes to hours)

• nervous system- brief (milliseconds)
• endocrine system- long (minutes to days or longer)

• nervous system- neurotransmitters released into synaptic cleft
• endocrine system- hormones released into blood

• nervous system- very short distances (diffused across synaptic cleft)
• endocrine system- long distance

• nervous system- close anatomical relationship between nerve cells and their target cells
• endocrine system- specificity of target cell binding and responsiveness of particular hormones

peptides/proteins

catecholamines (epi, norepi, dopamine)

steroid hormones

thyroid hormones

thyroxine

epinepherine

• needs to solubulized by other particles (carrier proteins) carried in the blood)
• carrier slowly release free testosterone which slips through cell membrane into cells (provide equilibrium between bound and free hormone)
  • testosterone transported by sex hormine binding globulin

• protein- secretory granules
• catecholamines- chromaffin granules

BOTH exocytosis of granules

• peptide- as free hormone
• catecholamines- half bound to plasma proteins

• peptide- channel changes or activation of second messanger system
• catecholamine- second messanger

• stored in colloid (inland extracellular site)
• secretion- via endocytosis of colloid
• transport in blood- mostly bound to plasma proteins (less than 0.5% free)
• receptor site- inside target cell
• mechanism of action- activation of genes to produce new proteins

• storage- stepwise modification of cholesterol in various intracellular compartments
• secrettion via simple diffusion
• mostly bound to plasma protein (5-10% free)
• receptor inside target cell
• mech. of action- activation of genes to produce new proteins

• set point
• negative feedback
• time of day

• energy balance- storage and breakdown of metabolites, energy production, met. rate
• homeostasis- regulation of blood volume, osmolarity, glucose, electrolytes
• reproduction
• growth and dev.
• environmental adaptation- adapt to temp, stressful situations, exams

1. hormone binds to receptor on cell membrane
2. second messanger system alters proteins
3. physiological response (rapid)

1. hormone difuse through cell and nuclear membrane
2. hormone binds to receptor on DNA
3. hormone receptor complex activate genes
4. cause protein synthesis

GH

ACTH

melatonin

1. light sensed by retinohypothalamic tract
2. suprachiasmatic nucleus receive signal and relay it to pineal gland
3. pineal gland will decrease melatonin secretion (secretion goes to hypothalamus)

Clinical use- use light to help reset circadian rhythm after flying across time zones (diurnal response is synchronized to light)

• paraventricular nucleus
• supraoptic nucleus
• process of release
  • travel down axons to terminals in posterior pituitary
  • release from terminal when excited

• enhance water reabsorption in principle cells of late DCT, CD
• if high, produces concentrated (hyperosmotic) urine
• vasomotor effects (secretion stimulated by hypovolemia)
  • enhance peripheral vasoconstriction

• excess water reabsorption and retention
• hyperosmotic urine
• hyponatremia

• reduced water reabsorption
• dilute polyuria
• dehydration and excess thirst

• ADH acts on both in:
  • V1- nephron
  • V2- smooth muscle of vessels

• Effects
  • ejection of milk from lactating mammary gland
  • contraction of uterus in labor
  • social attachment and bonding
• Stimulated by:
  • nursing
  • presence of infant
  • cervical dilation

• stimulate breast development
• stimulate milk secretion
• inhibit ovulation

• PRL will have excessive secretion
• use dopamine mimicers (ex: Bromocriptine)

stress

diurnal cycle

• exercise
• stress
• hypoglycemia
• diurnal cycle

• secreted from liver
• role- mediate responses of cartilage, bone, adipose tissue to GH
• INCREASES IN ADOLESCENCE

• arcuate nucleus
• Process
  • acts on somatotroph cells in anterior pituitary
  • G protein linked receptor to stimulate cAMP synthesis

• stimulated by GHRH
• inhibited by somatostatin

CAUSES PULSITILE RELEASE OF HORMONE!!!!!!!

• slightly increases right after birth
• stagnanbt in childhood
• peaks and dips in course of puberty
• adulthood stagnation and slight decreases

• protein synthesis and organ growth
  • AA uptake by cells
  • synthesis of RNA and DNA
• linear growth (direct and indirect effects)
  • enhances increase in bone length
  • enhances soft tissue mass during growth period
• insulin resistance (diabetogeneic)- decrease glucose uptake by cells, so increase in plasma glucose, increase lipolysis

postnatal

pubertal

1. interact with plasma membrane receptor
2. activate Ty kinases in cytoplasm to mediate gene expression
3. cause insulin resistance

• gigantism- excess GH in kids
  • stimulate epiphyses
• acromegaly- excess GH in aldults
  • increase bone thickness, organ size, hands and feet, tongue, facial features
  • insulin resistance and increased glucose intolerance lead to hyperglycemia

• kids
  • mild obesity
  • delayed puberty
  • treat with synthetic GH
• adult- accelerates aging

pregnancy

breast feeding

• excess (ex: prolactinoma)- failure to ovulate
• deficiency- failure to lactate

• PRL- amenorrhea
• GH- gigantism in kids
• LH, FSH- infertility
• ACTH- increase cortisol
• TSH- hyperthyroidism

• PRL- no lactation
• GH- dwarfism
• LH, FSH- gonadal insufficiency
• ACTH- adrenal insufficiency
• TSH- hypothyroidism