Open AccessAdrenalectomy Abolishes Fasting-induced Down-regulation of NADPH-diaphorase in the Rat Paraventricular Nucleus
Author(s) -
Jeong Won Jahng,
Jong Ho Lee,
Guntae Kim,
Yunmi Kim,
Thomas A. Houpt,
Dong Goo Kim
Publication year - 2004
Publication title -
yonsei medical journal/yonsei medical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.702
H-Index - 63
eISSN - 1976-2437
pISSN - 0513-5796
DOI - 10.3349/ymj.2004.45.1.123
Subject(s) - medicine , endocrinology , dexamethasone , parvocellular cell , adrenalectomy , nitric oxide synthase , nucleus , nadph dehydrogenase , nitric oxide , chemistry , biology , hypothalamus , microbiology and biotechnology
This study was conducted to define the molecular mechanism of fasting-induced down-regulation of neuronal nitric oxide synthase (nNOS) expression in the hypothalamic paraventricular nucleus (PVN). Rats were adrenalectomized (ADX), and then either underwent food deprivation or received varying doses of dexamethasone for 48 h. The brain tissues were processed for NADPH-diaphorase (NADPH-d) staining, a histochemical marker of nNOS enzyme activity. Both the ADX and the sham operated rats showed a significant weight loss after 48 h of food deprivation. Food deprivation decreased the number of NADPH-d containing cells in the PVN of sham rats, however, not in the ADX rats. Dexamethasone dose- dependently decreased NADPH-d cells in the PVN of ADX rats. The effect of ADX or dexamethasone was limited to the parvocellular subdivision of PVN. These results suggest that the adrenal glucocorticoids may down-regulate nNOS expression in the PVN during food deprivation.