|
Hormone |
Effect |
|
Renin |
· Enzymatic cleavage angiotensinogen -> angiotensin 1 (precursor to AT2) · No direct effect |
|
Angiotensin 2 |
· Cellular: AGTR – Gq G protein-coupled receptor (GPCR) -> ↑IP3/Ca2+, ↑DAG · Tubule: ↑Na+/HCO3-/H2O reabsorption at proximal tubule · Vascular: constrict efferent > afferent arterioles -> ↓peritubular hydrostatic pressure -> ↑reabsorption · CNS: ↑ADH release (see below) |
|
Aldosterone |
· Cellular: mineralocorticoid receptor – transcription factor -> ↑↓gene expression · Principal cell: ↑Na+K+ATPase synthesis and activity -> ↑ENaC and ROMK activity-> ↑Na+/↓K+ reabsorption · Type 1 intercalated cell: ↑H+ATPase activity -> ↓H+ reabsorption · Indirect effect: ↑ECF osmolality -> ↑ADH -> ↑H2O reabsorption · Cortisol causes same effects but to a lesser extent |
|
ADH |
· Cellular: V2R – Gs GPCR -> ↑cAMP · Collecting ducts: insert aquaporins into apical membrane -> ↑H2O reabsorption · Medullary collecting ducts: insert ureaporins into apical membrane -> urea recycling -> ↑interstitial osmolality -> facilitate H2O absorption · Thick ascending loop of Henle: ↑Na+ reabsorption |
|
ANP |
· Vascular: dilate afferent and efferent arterioles -> ↑GFR, ↑vasa recta flow, ↑washout of medullary interstitium -> ↓reabsorption · Distal tubule: inhibit NCC -> ↓Na+Cl- reabsorption · Collecting duct: inhibit ENaC -> ↓Na+ reabsorption |
|
Adrenaline |
· Cellular: β1 Gs GPCR -> ↑cAMP; α1 Gq GPCR -> ↑[Ca2+] · Vascular (β1): juxtaglomerular cell -> ↑renin-angiotensin-aldosterone activity (see above) · Proximal tubule (α1): ↑Na+/HCO3- absorption |
|
PTH |
· Cellular: PTHR: Gs GPCR -> ↑cAMP · Proximal tubule: ↓PO43- reabsorption · Distal tubule: ↑Ca2+ reabsorption |
|
Vitamin D3 |
· Cellular: VDR - nuclear transcription factor -> ↑↓gene transcription · Proximal tubule: ↑PO43- reabsorption · Distal tubule: ↑Ca2+ reabsorption |
|
Calcitonin |
· Cellular: CTR – GPCR multiple types · Proximal tubule: ↓PO43- reabsorption · Distal tubule: ↓Ca2+ reabsorption |