The regional hypothalamic distribution of type II 5'-monodeiodinase in euthyroid and hypothyroid rats.
The brain topographical distribution of type II 5'-monodeiodinase (5'D-II), which converts thyroxine (T4) to triiodothyronine (T3), was studied in euthyroid and hypothyroid rats. Low levels of 5'D-II activity were detected in the median eminence, but not in any other brain regions of euthyroid rats. The arcuate nucleus and median eminence were also the sites of highest 5'D-II activity in brains of hypothyroid rats. Under these conditions, the paraventricular nucleus contained almost no detectable 5'D-II, while intermediate enzyme activity was present in other medial basal hypothalamic sites.
Riskind
P N
PN
Department of Neurology, Massachusetts General Hospital, Boston 02114.
Kolodny
J M
JM
Larsen
P R
PR
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000201:enzymology / Q000503:physiopathology; D001921:Brain / Q000201:enzymology / Q000503:physiopathology; D007031:Hypothalamus / Q000201:enzymology* / Q000503:physiopathology; D007037:Hypothyroidism / Q000201:enzymology* / Q000503:physiopathology; D007453:Iodide Peroxidase / Q000378:metabolism*; D008297:Male; D008473:Median Eminence / Q000201:enzymology / Q000503:physiopathology; D008713:Methimazole; D051381:Rats; D011919:Rats, Inbred Strains; D013961:Thyroid Gland / Q000002:abnormalities* / Q000201:enzymology; D013974:Thyroxine / Q000378:metabolism; D014284:Triiodothyronine / Q000378:metabolism
D014284:Triiodothyronine; D008713:Methimazole; D007453:Iodide Peroxidase; D013974:Thyroxine