Renal Physiology pt 3 (Final Exam) Flashcards
What stimulates the Vasopressin release system?
- ↑ Serum osmolarity
- Hypotension
What receptors sense osmolarity?
Where are these located?
- Osmoreceptors
- Hypothalamus
5/6 of ADH release is determined from this structure.
Where is this located?
- Supraoptic Nuclei
- Anterior near optic nerves.
1/6 of ADH release is determined from what structure?
Where is this located?
- Paraventricular Nuclei
- Posterior; close to 3rd ventricle.
What are the two lobes of the pituitary gland?
Which of the two secretes vasopressin?
What coordinates with osmoreceptors & baroreceptors to induce vasopressin release?
- Adenohypophysis (anterior) & Neurohypophysis (posterior)
- Neurohypophysis secretes vaso
- Supraoptic & Paraventricular Nuclei.
What would occur with a cell if placed in a hypotonic solution?
- Swelling of the cell
What would occur with a cell if placed in a hypertonic solution?
- Cellular Shrinkage
What areas of the nephron are affected by ADH?
- Everywhere except the Proximal Tubule.
What areas are more affected by ADH?
- Descending thin limb
- Medullary collecting duct
What would occur immediately after head injury in regards to ADH?
What would occur over a longer period in this same trauma scenario?
- Short term: ADH release = SIADH
- Long term: no ADH = DI
What is a pathology characterized by excessive ADH called?
What things can cause this condition?
SIADH:
- Short term head trauma
- NSAIDs & opioids
- Anti-depressants (with high dose)
- Lung Cancer (lots of junk made by this cancer)
What pathology is characterized by insufficient levels of ADH?
What things can cause this condition?
Diabetes Insipidus:
- Head Injury (Long-term)
- EtOH
- Nephrogenic DI
What mechanism causes DI with EtOH use?
- EtOH inhibits release of ADH at the pituitary through Ca⁺⁺ current reduction.
What is nephrogenic DI?
What is an example of this condition?
- Inability of kidney to respond to ADH.
- Lithium - super high doses = 20L UO/day
What is the treatment for Central DI?
What type of drug is this?
- Desmopressin (DDAVP) - V2 Receptor Agonist.
What would characterize Addison’s disease?
What electrolyte abnormalities would be seen?
- Low Aldosterone
- ↓ Na⁺ & ↑ K⁺
What would characterize Conn’s Syndrome?
What would cause this?
What electrolyte abnormalities would be seen?
- High Aldosterone
- Adrenal Tumor causing hyperactivity
- ↓ K⁺ & ↑ Na⁺
What areas of the nephron are permeable to Urea?
- Proximal Tubule
- Thin descending limb
- Thin ascending limb
- Medullary Collecting Duct with ADH.
What areas of the nephron have NaCl permeability?
- Proximal Tubule
- Thin descending limb
- Thin ascending limb
What areas of the nephron are permeable to water?
- Proximal Tubule
- Thin Descending Limb
What areas of the nephron become permeable to water with ADH?
- Distal Tubule
- Cortical & Medullary Collecting Ducts
What areas of the nephron utilize active NaCl Transport?
- Proximal Tubule
- Thick Ascending Limb
- Distal Tubule
- Cortical & Medullary Collecting Duct
Everywhere except the thin limbs
What prevents volatility in serum sodium levels?
- ADH/Vasopressin System