Circadian variation of [3H]dopamine handling in adrenal chromaffin cells of mice.
Circadian variation of exogenous [3H]dopamine handling by adrenal chromaffin cells was examined using mice habituated to 08.00-20.00 h light cycle. Experiments were carried out at 00.00, 06.00, 12.00 and 18.00 h. [3H]Dopamine-derived radioactivity reached a peak at 2 min then decreased rapidly except at 18.00 h, when no particular peak was observed at 2 min but at 30 min in both intact and denervated adrenals. In intact adrenals, the 2-min peak at 06.00 h was suppressed by corticosterone while in denervated adrenals the 2-min peak remained. The present result indicates that quick turnover of [3H]dopamine was suppressed by a steroid surge at about 2 h before light to dark alteration. Normal innervation is necessary for corticosterone-induced suppression.
Hirano
T
T
Department of Physiology, Niigata University, School of Medicine, Japan.
Nagai
K
K
Nakagawa
H
H
D000311:Adrenal Glands / Q000294:innervation / Q000502:physiology; D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D003345:Corticosterone / Q000494:pharmacology; D003714:Denervation; D004298:Dopamine / Q000378:metabolism*; D004759:Enterochromaffin Cells / Q000378:metabolism*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains
D004298:Dopamine; D003345:Corticosterone