Abstract
We report here an examination of the effect of thioredoxin (TRX) on the secretion of growth hormone (GH) from rat anterior pituitary cells in vitro. Treatment of rat pituitary cells with growth hormone-releasing factor (GRF), but not GH, led to a significant increase in intracellular TRX protein levels. GRF, recombinant human TRX (rhTRX), and a combination thereof were all shown to induce immediate GH secretion from pituitary cells, as evidenced by perifusion experiments. RhTRX, but not other reducing agents such as β-mercaptoethanol and N-acetyl-L-cysteine, augmented GRF-stimulated and -unstimulated GH secretion from rat pituitary cells in a dose-dependent manner. RhTRX did not significantly affect the GH mRNA expression of pituitary cells stimulated in the presence or absence of GRF. In addition, rhTRX-augmented GH secretion was not significantly affected by the presence of cycloheximide. Collectively, these findings suggest that TRX is induced by stimulation with GRF and plays a regulatory role in GH secretion from rat anterior pituitary cells by enhancing the secretion of stored GH, rather than by the synthesis of GH.
| Original language | English |
|---|---|
| Journal | American Journal of Physiology - Endocrinology and Metabolism |
| Volume | 281 |
| Issue number | 2 44-2 |
| Publication status | Published - 2001 |
| Externally published | Yes |
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Keywords
- Disulfide bonds
- Growth hormone-releasing factor
- Redox
ASJC Scopus subject areas
- Physiology
- Endocrinology
- Biochemistry
- Physiology (medical)
Cite this
Involvement of thioredoxin in the regulation of growth hormone secretion in rat pituitary cell cultures. / Hata, Ikue; Shigematsu, Yosuke; Ohshima, Yusei; Tsukahara, Hirokazu; Fujisawa, Kazuo; Hiraoka, Masahiro; Nakamura, Hajime; Masutani, Hiroshi; Yodoi, Junji; Kotsuji, Fumikazu; Sudo, Masakatsu; Mayumi, Mitsufumi.
In: American Journal of Physiology - Endocrinology and Metabolism, Vol. 281, No. 2 44-2, 2001.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Involvement of thioredoxin in the regulation of growth hormone secretion in rat pituitary cell cultures
AU - Hata, Ikue
AU - Shigematsu, Yosuke
AU - Ohshima, Yusei
AU - Tsukahara, Hirokazu
AU - Fujisawa, Kazuo
AU - Hiraoka, Masahiro
AU - Nakamura, Hajime
AU - Masutani, Hiroshi
AU - Yodoi, Junji
AU - Kotsuji, Fumikazu
AU - Sudo, Masakatsu
AU - Mayumi, Mitsufumi
PY - 2001
Y1 - 2001
N2 - We report here an examination of the effect of thioredoxin (TRX) on the secretion of growth hormone (GH) from rat anterior pituitary cells in vitro. Treatment of rat pituitary cells with growth hormone-releasing factor (GRF), but not GH, led to a significant increase in intracellular TRX protein levels. GRF, recombinant human TRX (rhTRX), and a combination thereof were all shown to induce immediate GH secretion from pituitary cells, as evidenced by perifusion experiments. RhTRX, but not other reducing agents such as β-mercaptoethanol and N-acetyl-L-cysteine, augmented GRF-stimulated and -unstimulated GH secretion from rat pituitary cells in a dose-dependent manner. RhTRX did not significantly affect the GH mRNA expression of pituitary cells stimulated in the presence or absence of GRF. In addition, rhTRX-augmented GH secretion was not significantly affected by the presence of cycloheximide. Collectively, these findings suggest that TRX is induced by stimulation with GRF and plays a regulatory role in GH secretion from rat anterior pituitary cells by enhancing the secretion of stored GH, rather than by the synthesis of GH.
AB - We report here an examination of the effect of thioredoxin (TRX) on the secretion of growth hormone (GH) from rat anterior pituitary cells in vitro. Treatment of rat pituitary cells with growth hormone-releasing factor (GRF), but not GH, led to a significant increase in intracellular TRX protein levels. GRF, recombinant human TRX (rhTRX), and a combination thereof were all shown to induce immediate GH secretion from pituitary cells, as evidenced by perifusion experiments. RhTRX, but not other reducing agents such as β-mercaptoethanol and N-acetyl-L-cysteine, augmented GRF-stimulated and -unstimulated GH secretion from rat pituitary cells in a dose-dependent manner. RhTRX did not significantly affect the GH mRNA expression of pituitary cells stimulated in the presence or absence of GRF. In addition, rhTRX-augmented GH secretion was not significantly affected by the presence of cycloheximide. Collectively, these findings suggest that TRX is induced by stimulation with GRF and plays a regulatory role in GH secretion from rat anterior pituitary cells by enhancing the secretion of stored GH, rather than by the synthesis of GH.
KW - Disulfide bonds
KW - Growth hormone-releasing factor
KW - Redox
UR - http://www.scopus.com/inward/record.url?scp=0034889751&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034889751&partnerID=8YFLogxK
M3 - Article
C2 - 11440902
AN - SCOPUS:0034889751
VL - 281
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
SN - 0193-1849
IS - 2 44-2
ER -