Cellular Adaptive Responses Flashcards
2 Forms of Adaptive Responses
- 1)To physiological (normal) stimuli / adaptation*
- 2) To pathological (disease) stimuli / adaptation*
5 Key Methods of Cellular Adaptation
•Hypertrophy
- Hyperplasia
- Atrophy
- Metaplasia
- Dysplasia
- (Neoplasia)
__________________: Increase in size of cells resulting in increased size of the organ -No new cells
Examples?
Hypertrophy: Increase in size of cells resulting in increased size of the organ -No new cells
Physiologic –enlargement of the cell of the uterus during pregnancy driven by estrogen
Pathologic –cardiac myocyte enlargement due to workload
____________:
Increase in cell numbers due to increased proliferation. Replacement by tissue stem cells
–New cells
–But controlled(so not cancer –uncontrolled)
Physiologic:
- ____________ –proliferation of glandular epithelium of female breast at puberty and pregnancy.
- ____________ –liver regrowth following resection
Pathologic:
•___________________________
Hyperplasia:
Increase in cell numbers due to increased proliferation. Replacement by tissue stem cells
–New cells
–But controlled(so not cancer –uncontrolled)
Physiologic:
- Hormonal hyperplasia –proliferation of glandular epithelium of female breast at puberty and pregnancy.
- Compensatory hyperplasia –liver regrowth following resection
Pathologic:
•Connective tissue growth during wound healing
The cells making up the glands are normal in appearance but have increased numbers. What is this called? What are its consequences?
Benign Prostatic Hyperplasia
The prostate is going to become enlarged, pressure on urethra difficulty in urinating
The bladder would expand in size, stretch
Muscles have to work harder to urinate, they hypertrophy, getting bigger and bigger and bigger
Treatment of Benign Prostatic Hyperplasia
What are their Mechanisms?
5-alpha reductase inhibitors
–Dutasteride, finasteride
–Inhibit the conversion of Testosterone to DHT
–Side effect? Muscle wastage, bones weaker
Alpha-blockers
–Tamsulosin, doxazosin
–Relax the muscles of the prostate
Surgery
–Transurethral resection of the prostate (TURP)
_____________: Shrinkage in the size of a cell by the loss of cell substance –due to decreased protein synthesis or degradation in the cell.
Physiologic/Pathologic examples?
Atrophy
Shrinkage in the size of a cell by the loss of cell substance –due to decreased protein synthesis or degradation in the cell.
–Physiologic –loss of hormone stimulation –menopause
–Pathologic –denervation or immobilization of a muscle leading to the decreased size.
________________:
Reversible change in which one adult cell type is replaced by another adult cell type
–Reprogramming of stem cells down another differentiation pathway rather than a change in the phenotype of an existing differentiated cell type –which can better deal with the stress
Example?
Metaplasia
Reversible change in which one adult cell type is replaced by another adult cell type
–Reprogramming of stem cells down another differentiation pathway rather than a change in the phenotype of an existing differentiated cell type –which can better deal with the stress
change cell type exposed to changing environment such as smoking
______________:
Premalignant condition characterized by the loss of uniformity of the individual cells as well as loss in architectural orientation –“looks abnormal” –large nuclei
- Irregularity that hinders cell maturation
- Is reversible if the stimulus causing the change is removed
What are the benefits of screening for?
Dysplasia:
- Premalignant condition characterised by the loss of uniformity of the individual cells as well as loss in architectural orientation –“looks abnormal” –large nuclei
- Irregularity that hinders cell maturation
- Is reversible if stimulus causing the change is removed
–May be present for many years before malignant neoplasma develops –Important of screening
___________: Not reversible if the stimulus causing the change is removed
Neoplasia
•Not reversible if stimulus causing the change is removed
_______________:
“Change in form”
Reversible
Substitution of a distinct cell with another mature cell
Metaplasia
“Change in form”
Reversible
Substitution of a distinct cell with another mature cell
_____________:
“Bad Formation”
Looks abnormal
Reversible
Irregularity that hinders cell Maturation
Pre-cancerous but reversible
Dysplasia
“Bad Formation”
Looks abnormal
Reversible
Irregularity that hinders cell Maturation
Pre-cancerous but reversible
__________
“Bad Formation”
Looks abnormal
Not reversible
Neoplasia
“Bad Formation”
Looks abnormal
Not reversible
