Weeks 1 - 3 Flashcards
Give an example of physiologic atrophy:
(3)
- Thymus decreased in size during childhood.
- Uterus decreases in size after child birth.
- Tonsils shrink in adolescents.
Causes of pathological atrophy:
(3/6)
- Decrease in workload
- Decrease in use, pressure, blood supply
- Decrease in hormonal stimulation or nutrition.
Give an example of pathologic atrophy:
(1)
Disuse atrophy: skeletal muscle after removal of a cast.
What is hypertrophy:
Increase in cell size
Give an example of physiologic hypertrophy:
Hypertrophy of myocardial cells (myocytes) as a result of endurance training.
Give an example of pathological hypertrophy:
HTN / heart valve dysfunction (chronic hemodynamic overload).
Prolonged hypertrophy = contractile dysfunction = heart failure.
What’s the difference between physiologic hypertrophy and pathologic hypertrophy regarding heart muscle:
• physiologic hypertrophy: cellular matrix is preserved.
• pathological hypertrophy: increased interstitial fibrosis, cell death, abnormal cardiac function.
What’s the difference between physiologic hypertrophy and pathologic hypertrophy regarding heart muscle:
• physiologic hypertrophy: cellular matrix is preserved.
• pathological hypertrophy: increased interstitial fibrosis, cell death, abnormal cardiac function.
What is hyperplasia?
Increased cellular division rate which increases NUMBER of cells
What is the process of hyperplasia?
• Injury = severe / prolonged damage = cell death.
• Production of hormone / growth factors = remaining cells synthesize cell components = mitosis (cell division).
• Increased output from tissue stem cells.
Give an example of pathological hyperplasia:
Benign prostatic hyperplasia (BPH)
Mature cells have a differing capacity for hyperplastic or ____________ growth.
Mitotic
What is metaplasia?
REPLACEMENT if cells
Give an example of metaplasia:
“Smokers Lungs” - reversible
Normal columnar violated epithelial cells of the bronchial lining have been replaced with stratified squamous epithelial cells.
6 major players of fluid balance:
• Hydrostatic pressure (water OUT of capillaries into surrounding tissue)
• Oncotic pressure (water INTO capillaries from surrounding tissue)
• Renin angiotensin-aldosterone system (RAAS)
• Aldosterone (think sodium)
• Antidiuretic Hormone (ADH) (think water)
• Natriuretic peptides (RAAS antagonist)
How Hydrostatic Pressure function?
Fluid moves from intravascular space to interstitial space via capillaries because capillary hydrostatic pressure (blood pressure) is higher than oncotic pressure.
Water moves from capillaries to interstitial space via blood pressure.
How does Oncotic Pressure function?
Influenced by plasma proteins (albumin).
Low plasma albumin = edema = decrease in Oncotic pressure = pulls fluid INTO capillary.
How does the Renin Angiotensin-Aldosterone System (RAAS) function?
• Renin is an enzyme secreted by juxtaglomerular cells in the kidney.
• Sympathetic nerve stimulation and decreased perfusion of the renal vascular = low blood volume / pressure = renin release = cascade of antiotensins = vasoconstriction.
• Opposes natriuretic peptides
How does Aldosterone function?
• Regulates sodium and potassium
• Increased sodium and water decreased potassium.