Week 5 Hypertrophy Flashcards
define hypertrophy
increase in cell size which often leads to a concurrent increase in organ size and/or fxn
what are the two clinical settings in which hypertrophy is encountered
increased fucntional demand, increased trophic factors
a morbidly obese individual exercises and a year later is extremely fit/tone. Describe the changes in adipose and skeletal muscle that occurred
Fat: adipose was hypertrophied, skeletal muscle atrophy
Muscular: adipose atrophy, skeletal muscle hypertrophy
which relevant cell types do not divide? 2
skeletal and myocardial myocytes
when do we see cells/tissues/organs undergoing hypertrophy and proliferation
usually these go together UNLESS the cell does not divide; in which case we would only see hypertorphy
when do we see cells/tissues/organs undergoing atrophy and apoptosis?
usually these go together. Unless the cell type does not divide in which case we see atrophy without apoptosis
when exposed to trophic factors how do cells capable of proliferation respond? when factors withdrawn?
exposed: hyperplasia, hypertrophy
withdrawn: atrophy, apoptosis
how will a hypertrophic tissue appear when compared to a normal one?
larger
how will hypertrophic cells appear when compared to normal cells?
larger, with a larger nucleus
what can cause hypertrophy of the heart?2
hypertension (pathological), exercise (physiological)
what are trophic factors
factors such as hormones that promote cell growth, proliferation
what is a gravid uterus
a pregnant uterus whose endometrium grows (hypertrophy and hyperplasia due to estrogen). Pear–>grapefruit–>papaya–>watermelon
how do anabolic steroids work?
activate TFs that stimulate fetal gene expression of contractile proteins and increase their synthesis (leads to hypertrophy and increased muscle mass)
stretch receptors and binding of GFs to cardiac myocytes has what effect?
signal transduction that increases TFs for the re-induction of fetal genes (increased contractile proteins and increased GFs (autocrine effect))
