Term
| What is ADH and what does it do? |
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Definition
| anti-diuretic hormone (Vasopressin, AVP) is a peptide hormone the body synthesizes to regulate body fluid osmolality. |
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Term
Match to the appropriate function:
1. Hypothalamus
2. Pituitary
3. collecting duct of the kidney
4. vascular smooth muscle
A. Target site
B. Synthesis
C. Storage and release |
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Definition
Hypothalamus (synthesis)
pituitary (storage and release)
collecting duct and VSM (target site) |
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Term
| What stimulates release of ADH? |
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Definition
Hyponatremia (fastest response)
hypovolemia
angiotensin |
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Term
| What happens in the V2 receptor cascade when stimulated by hyponatremia/volemia? |
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Definition
ADH stimulates the V2 receptor to increase cAMP, which increases PKA which:
1. Increases the number and expression of aquaporins...this is NOT solute dependent! It's "free water" retention!
2. Increases the number/expression/translocation of Na/K/2Cl symporter (increase medullary tonicity)
3. Opens VRUT (vasopressin regulated urea transporters which increases the reabsorption of urea, and water follows.
NET EFFECT: increased medullary tonicity and increased water retention. |
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Term
| What is the Net effect from V2 stimulation? |
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Definition
| increased medullary tonicity and increased water retention |
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Term
| Where is the V2 receptor located? |
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Definition
| basolateral side of the principle cells in the collecting duct in the kidney |
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Term
| T/F The V1 receptor is more sensitive to ADH than the V2 receptor. |
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Definition
| False. V2 is more sensitive |
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Term
| What factors regulate coagulation with the ADH effects in the V2 receptors? |
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Definition
Factor VIII
Von Willebrand Factor |
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Term
| What is Vaprisol (Conavaptan HCl)? |
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Definition
V1/V2 antagonist. Net effect: blocks interaction between V1 and V2
Increase serum Na and Aquaresis (lose water)
Adverse effects: dropping BP too fast, hypokalemia, liver CYP450--3A4...keeps Na in lumen and keeps from retaining too much water. Keeps blood flowing properly |
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Term
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Definition
| control/regulate vascular smooth muscle (vasoconstriction/growth) throughout the body to control total peripheral resistance (decrease) |
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Term
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Definition
| helps innapropriate ADH release syndrome or hyponatremia |
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Term
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Definition
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Term
| What drugs increase ADH secretion? |
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Definition
Nicotine
Isoproterenol
Colchicine |
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Term
| What inhibits the secretion of ADH? |
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Definition
| ethanol, opiate agonists (k), glucocorticoids, phenytoin |
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Term
| What potentiates the secretion of ADH? |
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Definition
| Clofibrate, Chloropranide, Carbamazepine |
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Term
| What do NSAIDs do to renal AVP actions? |
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Definition
| NSAIDs (Indomethacin) enhances the anti-diuretic effect of AVP |
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Term
| What does Lithium and demeclocyline do to AVP actions? |
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Definition
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Term
| What causes diabetes insipidus? |
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Definition
central DI is caused by inadequate AVP secretion (tx: desmopressin)
nephrogenic DI is a result of a decreased responsiveness of the CD to AVP (not treatable w/ AVP agonists) |
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Term
| What are the therapeutic uses for AVP (arginine vasopressin) or Desmopressin? |
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Definition
Central Diabetes insipidus
nocturnal enuresis (nasal spray)
bleeding disorders (type 1 Von Willbrand disease)
SIADH |
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Term
| What does desmocycline do? |
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Definition
| blocks AVP action in the collecting duct. |
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Term
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Definition
| water restriction and demeclocyline (which blocks AVP action in the collecting duct) |
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Term
| Where is the location of the V1 receptors? |
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Definition
| adrenal gland, bladder, adipocytes, hepatocytes, platelets, myometrium, renal, etc |
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Term
| T/F The V1 shows that ADH regulates more than just water. |
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Definition
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Term
ADH-> V1
V1 splits into 3 categories. Explain each. |
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Definition
PLA: arachadonic acid
1. PG/thromboxanes: inhibit AC (which breaks the V2 receptor stimulation)
2. Leaukotrienes
PLD: DAG->cell growth and metabolism (slow)
PLC: IPS: increases Ca conc-> vasocontrict, glycogenolysis, platelet aggregation, ACTH release (Rapid) |
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Term
| What is the rapid V1 response? |
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Definition
ADH->V1->PLC->IP3->inc Ca:
Vasoconstriction, glycogenolysis, platelet aggregation, ACTH release |
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Term
| What is the slow V1 response? |
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Definition
PLD->DAG:
cell growth and metabolism |
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Term
| What happens when a V1 is sitting next to a V2? |
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Definition
| They turn each other off. |
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