Visualization of corticotropin-releasing factor neurons by fluorescent proteins in the mouse brain and characterization of labeled neurons in the paraventricular nucleus of the hypothalamus

Keiichi Itoi, Ashraf Hossain Talukder, Toshimitsu Fuse, Takuji Kaneko, Ryo Ozawa, Takayuki Sato, Takuma Sugaya, Katsuya Uchida, Maya Yamazaki, Manabu Abe, Rie Natsume, Kenji Sakimura

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Corticotropin-releasing factor (CRF) isthekeyregulatorofthehypothalamic-pituitary-adrenalaxis.CRF neurons cannot be distinguished morphologically from other neuroendocrine neurons in the paraventricular nucleus of the hypothalamus (PVH) without immunostaining. Thus, we generated a knock-in mouse that expresses modified yellow fluorescent protein (Venus) in CRF neurons (CRF-Venus), andyet its expression is drivenbytheCRFpromoterandresponds tochangesin the interior milieu. In CRF-Venus, Venus-expressing neurons were distributed in brain regions harboring CRF neurons, including thePVH.Themajority of Venus-expressing neurons overlapped with CRF-expressing neurons in the PVH, but many neurons expressed only Venus or CRF in a physiological glucocorticoid condition. After glucocorticoid deprivation, however, Venus expression intensified, and most Venus neurons coexpressed CRF. Conversely, Venus expression was suppressed by excess glucocorticoids. Expression of copeptin, a peptide encoded within the vasopressin gene, was induced in PVH-Venus neurons by glucocorticoid deprivation and suppressed by glucocorticoid administration. Thus, Venus neurons recapitulated glucocorticoid-dependent vasopressin expression in PVH-CRF neurons. Noradrenaline increased the frequency of glutamate-dependent excitatory postsynaptic currents recorded from Venusexpressing neurons in the voltage clamp mode. In addition, the CRF-iCre knock-in mouse was crossed with a CAG-CAT-EGFP reporter mouse to yield the TgCAG-CAT-EGFP/wt;CRFiCre/wt(EGFP/CRF-iCre) mouse, inwhichenhancedgreenfluorescentprotein(EGFP)isdrivenbytheCAGpromoter.EGFPwasexpressed more constitutively in the PVH of EGFP/CRF-iCre mice. Thus, CRF-Venus may have an advantage for monitoring dynamic changes in CRF neurons and CRF networks in different glucocorticoid states. Copyright

Original languageEnglish
Pages (from-to)4054-4060
Number of pages7
JournalEndocrinology
Volume155
Issue number10
DOIs
Publication statusPublished - 2014 Oct 1

ASJC Scopus subject areas

  • Endocrinology

Fingerprint Dive into the research topics of 'Visualization of corticotropin-releasing factor neurons by fluorescent proteins in the mouse brain and characterization of labeled neurons in the paraventricular nucleus of the hypothalamus'. Together they form a unique fingerprint.

  • Cite this