Invalidation of TASK1 potassium channels disrupts adrenal gland zonation and mineralocorticoid homeostasis.
TASK1 (KCNK3) and TASK3 (KCNK9) are two-pore domain potassium channels highly expressed in adrenal glands. TASK1/TASK3 heterodimers are believed to contribute to the background conductance whose inhibition by angiotensin II stimulates aldosterone secretion. We used task1-/- mice to analyze the role of this channel in adrenal gland function. Task1-/- exhibited severe hyperaldosteronism independent of salt intake, hypokalemia, and arterial 'low-renin' hypertension. The hyperaldosteronism was fully remediable by glucocorticoids. The aldosterone phenotype was caused by an adrenocortical zonation defect. Aldosterone synthase was absent in the outer cortex normally corresponding to the zona glomerulosa, but abundant in the reticulo-fasciculata zone. The impaired mineralocorticoid homeostasis and zonation were independent of the sex in young mice, but were restricted to females in adults. Patch-clamp experiments on adrenal cells suggest that task3 and other K+ channels compensate for the task1 absence. Adrenal zonation appears as a dynamic process that even can take place in adulthood. The striking changes in the adrenocortical architecture in task1-/- mice are the first demonstration of the causative role of a potassium channel in development/differentiation.
Heitzmann
Dirk
D
Institute of Physiology, University of Regensburg, Regensburg, Germany.
Derand
Renaud
R
Jungbauer
Stefan
S
Bandulik
Sascha
S
Sterner
Christina
C
Schweda
Frank
F
El Wakil
Abeer
A
Lalli
Enzo
E
Guy
Nicolas
N
Mengual
Raymond
R
Reichold
Markus
M
Tegtmeier
Ines
I
Bendahhou
Saïd
S
Gomez-Sanchez
Celso E
CE
Aller
M Isabel
MI
Wisden
William
W
Weber
Achim
A
Lesage
Florian
F
Warth
Richard
R
Barhanin
Jacques
J
D000311:Adrenal Glands / Q000378:metabolism* / Q000473:pathology; D000450:Aldosterone / Q000097:blood / Q000378:metabolism; D000818:Animals; D005260:Female; D006706:Homeostasis / Q000235:genetics*; D006929:Hyperaldosteronism / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008901:Mineralocorticoids / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors / Q000172:deficiency* / Q000235:genetics*; D011188:Potassium / Q000097:blood; D024683:Potassium Channels, Tandem Pore Domain / Q000037:antagonists & inhibitors / Q000172:deficiency* / Q000235:genetics*; D012083:Renin / Q000097:blood
D008901:Mineralocorticoids; D009419:Nerve Tissue Proteins; D024683:Potassium Channels, Tandem Pore Domain; C420132:potassium channel subfamily K member 3; D000450:Aldosterone; D012083:Renin; D011188:Potassium