TY - JOUR
T1 - Expression and distribution of heme oxygenase-1 and -2 in rat brown adipose tissue
T2 - The modulatory role of the noradrenergic system
AU - Giordano, Antonio
AU - Nisoli, Enzo
AU - Tonello, Cristina
AU - Cancello, Raffaella
AU - Carruba, Michele O.
AU - Cinti, Saverio
PY - 2000/12/29
Y1 - 2000/12/29
N2 - To investigate whether brown adipose tissue (BAT) expresses the inducible (HO-1) and the constitutive (HO-2) isoform of heme oxygenase, reverse transcriptase-polymerase chain reaction, Western blotting and immunohistochemistry were performed on interscapular BAT (IBAT) from rats acclimated at environmental temperature or exposed to cold. Both HO isoforms were detected in rat IBAT. They were immunolocalized in the cytoplasm and/or nuclei of brown adipocytes, in parenchymal capillaries, arteries and in some veins and nerves. Whereas cold exposure did not affect HO-2 expression, it significantly increased the expression of HO-1, both at mRNA (about 3-fold) and protein (about 2-fold) levels, reflecting the increased expression of HO-1 in the brown adipocytes and endothelial cells of parenchymal capillaries. Western blotting of cytosolic and nuclear protein extracts from cultured differentiated brown adipocytes showed that HO-1 and HO-2 are indeed localized in the cytosol and nuclei of brown adipocytes, and that noradrenaline stimulation significantly increased their amount in cytosol but not in the nuclear fraction.
AB - To investigate whether brown adipose tissue (BAT) expresses the inducible (HO-1) and the constitutive (HO-2) isoform of heme oxygenase, reverse transcriptase-polymerase chain reaction, Western blotting and immunohistochemistry were performed on interscapular BAT (IBAT) from rats acclimated at environmental temperature or exposed to cold. Both HO isoforms were detected in rat IBAT. They were immunolocalized in the cytoplasm and/or nuclei of brown adipocytes, in parenchymal capillaries, arteries and in some veins and nerves. Whereas cold exposure did not affect HO-2 expression, it significantly increased the expression of HO-1, both at mRNA (about 3-fold) and protein (about 2-fold) levels, reflecting the increased expression of HO-1 in the brown adipocytes and endothelial cells of parenchymal capillaries. Western blotting of cytosolic and nuclear protein extracts from cultured differentiated brown adipocytes showed that HO-1 and HO-2 are indeed localized in the cytosol and nuclei of brown adipocytes, and that noradrenaline stimulation significantly increased their amount in cytosol but not in the nuclear fraction.
KW - Brown adipose tissue
KW - Heat shock protein 32
KW - Heme oxygenase
KW - Noradrenaline
KW - Rat
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U2 - 10.1016/S0014-5793(00)02217-1
DO - 10.1016/S0014-5793(00)02217-1
M3 - Article
C2 - 11150503
AN - SCOPUS:0034731313
VL - 487
SP - 171
EP - 175
JO - FEBS Letters
JF - FEBS Letters
SN - 0014-5793
IS - 2
ER -