title: Highly visible expression of an oxytocin-monomeric red fluorescent protein 1 fusion gene in the hypothalamus and posterior pituitary of transgenic rats.
abstract: We have generated rats bearing an oxytocin (OXT)-monomeric red fluorescent protein 1 (mRFP1) fusion transgene. The mRFP1 fluorescence was highly visible in ventral part of the supraoptic nucleus (SON) and the posterior pituitary in a whole mount. mRFP1 fluorescence in hypothalamic sections was also observed in the SON, the paraventricular nucleus (PVN), and the internal layer of the median eminence. Salt loading for 5 d caused a marked increase in mRFP1 fluorescence in the SON, the PVN, the median eminence, and the posterior pituitary. In situ hybridization histochemistry revealed that the expression of the mRNA encoding the OXT-mRFP1 fusion gene was observed in the SON and the PVN of euhydrated rats and increased dramatically after chronic salt loading. The expression of the endogenous OXT and the arginine vasopressin (AVP) genes were significantly increased in the SON and the PVN after chronic salt loading in both nontransgenic and transgenic rats. These responses were not different between male and female rats. Compared with nontransgenic rats, euhydrated and salt-loaded male and female transgenic rats showed no significant differences in plasma osmolality, sodium concentration, OXT, and AVP levels. Finally, we succeeded in generating a double-transgenic rat that expresses both the OXT-mRFP1 fusion gene and the AVP-enhanced green fluorescent protein fusion gene. Our new transgenic rats are valuable new tools to study the physiology of the hypothalamo-neurohypophysial system.
authors.affiliation: Department of Physiology, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Katoh
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Fujihara
authors.forename: Toyoaki
authors.initials: T
authors.lastname: Ohbuchi
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Onaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kawata
authors.forename: Hideaki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ueta
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000097:blood / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007030:Hypothalamo-Hypophyseal System / Q000166:cytology / Q000378:metabolism*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008473:Median Eminence / Q000166:cytology / Q000378:metabolism; D057054:Molecular Imaging / Q000379:methods*; D009419:Nerve Tissue Proteins / Q000097:blood / Q000235:genetics / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009928:Organ Specificity; D010121:Oxytocin / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D010286:Paraventricular Hypothalamic Nucleus / Q000166:cytology / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D055647:Rats, Transgenic; D017208:Rats, Wistar; D011993:Recombinant Fusion Proteins / Q000378:metabolism*; D012727:Sex Characteristics; D017673:Sodium Chloride, Dietary / Q000009:adverse effects; D013495:Supraoptic Nucleus / Q000166:cytology / Q000378:metabolism; D014882:Water-Electrolyte Balance; D000097573:Red Fluorescent Protein
chemical_list: D001127:Arginine Vasopressin; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D009419:Nerve Tissue Proteins; D010121:Oxytocin; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D017673:Sodium Chloride, Dietary; D000097573:Red Fluorescent Protein; C485184:enhanced green fluorescent protein