Unit 4 - Disturbances of Differentiation & Cell Growth Flashcards
an increased in the substance of an organ or tissue due to an increase in the NUMBER of parenchymal cells
hyperplasia
an increase in the substance of an organ or tissue due to an increase in the SIZE of already existing cells. No new cells added.
hypertrophy
___________ may occur in any tissue or organ, but ________ occurs only in those tissues whose cells retain the capacity for prolideration:
(In order): hypertrophy, hyperplasia
These processes are closely related and may develop concurrently in the same tissue or organ:
hypertrophy, hyperplasia
What type of tissues usually respond with hypertrophy?
smooth and skeletal muscle
What tissue types respond with hyperplasia?
lymphoid tissue, spleen, bone marrow
What is the etiology for both hyperplasia and hypertrophy?
- increased functional demand/work load, and/or endocrine stimulation or excessive nutrition
What is the pathogenesis for both hyperplasia and hypertrophy?
- increased work load
- increased metabolic activity of cells
- proliferation of golgi complex or RER due to increased # of mitochondria
When much of the function of one kidney is lost, hypertrophy occurs in the remaining kidney:
compensatory hypertrophy
What is the physiologic response of the body to a thrombus on the aortic valve?
interferes with blood leaving left ventricle –> increases pressure in left ventricle increased work load –> myocardial fibers stretch and increase in size –> hypertrophy of left ventricular myocardium
Hypertrophy in muscles is caused by?
increase in muscular activity which increases blood and nutrient supply –> increases muscle fiber size
How can iodine deficiency cause hypertrophy?
overwork of thyroid to compensate –> enlargement –> goiter
What is helpful in differentiating neoplasia from hyperplasia?
in hyperplasia, the tissue looks structurally the same - just larger
neoplasia, particularly malignant neoplasia will cause:
destruction of the tissue
What are the two exceptions to hyperplasia NOT destroying tissue?
nodular hyperplasia in the liver and spleen
replacement of the bone by reactive hyperplasia of fibrous CT is called:
fibrous osteodystrophy
Not associated with hepatocellular dysfunction but must be distinguished from hepatic neoplasms:
nodular hyperplasia of the liver
Excessive growth of pancreatic exocrine tissue with unknown cause and lack of clinical signs:
nodular hyperplasia in the pancreas
Which organ is a common site for cancer of endothelial cells? What is this cancer called?
spleen; hemangiosarcoma
Nodules of hyperplasia on the spleen are of no consequence unless:
they form hemotomas
white plaques along the margin of the head of the spleen that are a common incidental finding:
sidero-calcific plaques
Common in old dogs and are likely a consequence of minor previous hemorrhage:
sidero-calcific plaques
Hepatic coccidiosis in the rabbit is caused by Eimeria stiedae. Forsly, we see this lesion as white raised nodular areas. What are they actually?
distended bile ducts due to hyperplasia
What is a common sequela of E. stiedae distending the bile ducts?
icterus
