CELLULAR ADAPTATIONS HIGH YIELD Flashcards
pathology encompasses what aspects of the discipline?
etiology
pathogenesis
morphology
clinical signs and symptoms
cells react to adverse influences by?
adapting
sustaining reversible/irreversible injury and dying
what is the affect of increased workload and cell injury on myocytes?
adapted myocyte leading to hypertrophy
irreversibly injured myocyte leading to cell death
atrophy causes?
decreased workload loss of innervation decreased blood supply inadequate nutrition loss of endocrine stimulation aging pressure
what is the mechanism of atrophy?
decreased protein synthesis, so increased protein degradation
increased autophagy
cellular protein degradation occurs mainly by _____?
ubiquitin proteasome pathway
three principles that describe the morphology of atrophy?
loss of cellular constituents
autophagic vacuoles
residual bodies
what are the causes of hypertrophy?
increased functional demand
physiologic (uterus in preg)
pathologic (LVD)
what are the mechanisms of hypertrophy affecting the heart?
mechanical: stretch
trophic: soluble mediators that stimulate cell growth via gene activation, i.e- switch from adult to fetal contractile protein
the affect of morphology on hypertrophy?
fragmentation and loss of myofibrillar contractile elements known as degenerative changes which can lead to cardiac failure
cause for hyperplasia?
mechanisms?
physiologic(hormonal) and pathologic
mostly due to hormonal imbalances estrogen/progesterone
what are the causes of metaplasia?
chronic irritation
chronic inflammation
based on principle: replacement of cells sensitive to stress with those better able to withstand it
smoking is an example of chronic inflammation due to metaplasia that results in columnar respiratory epithelium being replaced by what cells?
squamous cells
what is the mechanism of metaplasia?
result of reprogramming of stem cells from cytokines, GFs, ECM components not from phenotype changes of the differentiated cell
