title: Up-regulation of vasopressin and angiotensin II receptors in the thalamus and brainstem of inbred polydipsic mice.
abstract: Vasopressin (AVP), angiotensin II (Ang II) and oxytocin (OT) receptors were mapped in the brain of inbred polydipsic mice of the STR/N strain by quantitative in vitro autoradiography and receptor binding levels, compared with those found in control non-polydipsic mice of the ICR strain. A remarkable difference was evidenced in the thalamic paraventricular nucleus where AVP receptor binding was 7- to 10-fold higher in polydipsic mice than in control mice. Another disparity was observed in the hypothalamic paraventricular nucleus, which contained AVP binding sites in the control mice, but was unlabelled in the polydipsic animals. Ang II receptor binding was reduced in the hypothalamic paraventricular nucleus of the polydipsic mice, whereas it was abundant in the brainstem region, encompassing area postrema and the nucleus of the solitary tract. The distribution and amount of OT receptor binding were similar in the polydipsic and control mice. Strain-related differences of AVP and Ang II receptor binding were observed both in male and female animals. A sex-related difference was seen only for OT receptor binding in the hypothalamic ventromedial nucleus, where labelling was less intense in males than in females of both strains. Altogether, our results support the view that central AVP and Ang II systems are involved in the mechanisms responsible for polydipsia in STR/N mice.
authors.affiliation: Department of Physiology, University Medical Center, Geneva, Switzerland. eliane.tribollet@medecine.unige.ch
authors.forename: Eliane
authors.initials: E
authors.lastname: Tribollet
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ueta
authors.forename: Freddy
authors.initials: F
authors.lastname: Heitz
authors.forename: Anouk
authors.initials: A
authors.lastname: Marguerat
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Koizumi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamashita
mesh_terms: D000804:Angiotensin II / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D004326:Drinking / Q000502:physiology*; D005260:Female; D007457:Iodine Radioisotopes; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008817:Mice, Mutant Strains; D020644:Midline Thalamic Nuclei / Q000378:metabolism*; D010121:Oxytocin / Q000378:metabolism / Q000494:pharmacology; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism; D011141:Polyuria / Q000503:physiopathology; D011869:Radioligand Assay; D011945:Receptors, Angiotensin / Q000378:metabolism*; D018045:Receptors, Oxytocin / Q000378:metabolism; D017483:Receptors, Vasopressin / Q000378:metabolism*; D012727:Sex Characteristics; D017552:Solitary Nucleus / Q000378:metabolism*; D015854:Up-Regulation / Q000502:physiology; D014697:Ventromedial Hypothalamic Nucleus / Q000378:metabolism
chemical_list: D007457:Iodine Radioisotopes; D011945:Receptors, Angiotensin; D018045:Receptors, Oxytocin; D017483:Receptors, Vasopressin; D000804:Angiotensin II; D010121:Oxytocin; C074793:angiotensin II, Sar(1)-