Adrenal 11-beta hydroxysteroid dehydrogenase activity in response to stress.
This work studied the effect of stresses produced by simulated gavage or gavage with 200 mmol/L HCl two hours before adrenal extraction, on the activities of the 11beta-hydroxysteroid dehydrogenase 1 and 11beta-hydroxysteroid dehydrogenase 2 isoforms present in the rat adrenal gland. These activities were determined on immediately prepared adrenal microsomes following incubations with 3H-corticosterone and NAD+ or NADP+. 11-dehydrocorticosterone was measured as an end-product by TLC, and controls were adrenal microsomes from rats kept under basal (unstressed) conditions. 11beta-hydroxysteroid dehydrogenase 1 activity, but not 11beta-hydroxysteroid dehydrogenase 2 activity, was increased under both stress-conditions. Homeostatically, the stimulation of 11beta-hydroxysteroid dehydrogenase 1 activity would increase the supply of glucocorticoids. These, in turn, would activate the enzyme phenylethanolamine N-methyl transferase, thereby improving the synthesis of epinephrine as part of the stress-response.
Zallocchi
Marisa
M
Dpto. Química Biológica, Facultad de Ciencias Exactas y Naturales (UBA), Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina. mzallo@qb.fcen.uba.ar
Matković
Laura
L
Damasco
María C
MC
D042842:11-beta-Hydroxysteroid Dehydrogenases / Q000096:biosynthesis / Q000378:metabolism*; D000311:Adrenal Glands / Q000201:enzymology*; D000818:Animals; D004789:Enzyme Activation / Q000502:physiology; D008297:Male; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley
D042842:11-beta-Hydroxysteroid Dehydrogenases