Differential redistribution of protein kinase C in human aldosteronoma cells and adjacent adrenal cells stimulated with ACTH and angiotensin II.
We have examined protein kinase C activity and hormone secretion in aldosteronoma cells derived from adrenocortical glomerulosa cells and in adjacent adrenal cells containing adrenocortical fasciculata-reticularis cells. When aldosteronoma cells were stimulated with ACTH or angiotensin II, protein kinase C activity gradually decreased in cytosol whereas it increased in membrane. Coincident with the changes of protein kinase C activity, there was enhancement of secretion of aldosterone. On the other hand, incubation of adjacent adrenal fasciculata-reticularis cells with ACTH induced cortisol secretion and an increase in cytosolic protein kinase C activity, accompanied by a decrease in the enzyme activity in membrane. Upon stimulation with angiotensin II, adjacent adrenal fasciculata-reticularis cells did not secrete cortisol and no significant changes of protein kinase C activities were observed in either cytosolic or membrane fractions. These results indicate that both ACTH and angiotensin II stimulate aldosterone secretion and cause translocation of protein kinase C from cytosol to membranes in aldosteronoma cells, whereas, in fasciculata-reticularis cells, only ACTH stimulates cortisol secretion and this is associated with translocation of protein kinase C in the opposite direction, viz., from membrane to cytosol.
Ishizuka
T
T
Third Department of Internal Medicine, Gifu University School of Medicine, Japan.
Miura
K
K
Nagao
S
S
Nozawa
Y
Y
D000302:Adrenal Cortex / Q000187:drug effects / Q000201:enzymology*; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000450:Aldosterone / Q000378:metabolism*; D000804:Angiotensin II / Q000494:pharmacology*; D004789:Enzyme Activation; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D006929:Hyperaldosteronism / Q000201:enzymology*; D011493:Protein Kinase C / Q000032:analysis*
D000804:Angiotensin II; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; D011493:Protein Kinase C; D006854:Hydrocortisone