ABSTRACT
Recent evidence indicates that renin transgenic rats TGR(mRen2)27 (TGR) manifest increased activity of the central vasopressinergic system. Because one of the reasons for this finding could be an increased synthesis of vasopressin receptors, we determined in the present study expression of V1a and V1b vasopressin receptors (R) mRNA in the brain of TGR rats and of their parent Sprague-Dawley (SD) strain. Competitive PCR method was applied for quantitative analysis of V1a and V1b receptors mRNA in the preoptic, diencephalic, mesencephalopontine and medullary regions. V1aR mRNA expression was similar in SD and TGR rats in the preoptic, diencephalic and mesencephalopontine regions. In the medullary region expression of V1aR mRNA was significantly lower in TGR than in SD rats. V1bR mRNA did not differ in TGR and SD rats in the preoptic, diencephalic and medullary region whereas it was significantly elevated in the mesencephalopontine region. The results provide evidence for differential regulation of V1a and V1b receptors genes in the brain stem of TGR rats that is manifested by downregulation of V1aR mRNA in the medulla and upregulation of V1bR mRNA in the mesencephalopontine region.
Subject(s)
Brain/metabolism , Receptors, Vasopressin/biosynthesis , Animals , Animals, Genetically Modified , Male , Polymerase Chain Reaction , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Receptors, Vasopressin/genetics , Renin/genetics , Renin/metabolismABSTRACT
Vasopressin plays significant role in regulation of blood pressure by means of V1 and V2 receptors, however regulation of synthesis of these receptors in hypertension is only poorly recognized. The purpose of the present study was to compare expression of V1a, V1b and V2 vasopressin (R) mRNA in the renal cortex, renal medulla and the heart of hypertensive renin transgenic TGR(mRen2)27 rats (TGR) and of their parent normotensive Sprague Dawley (SD) strain. The study was performed on 12 weeks old TGR and SD rats. Competitive PCR method was used for quantitative analysis of V1a, V1b and V2 receptors mRNA in fragments of renal cortex, renal medulla and apex of the left ventricle of the heart. In both strains expression of V1aR and V2R mRNA was significantly greater in the renal medulla than in the renal cortex. In the renal medulla but not in the cortex expression of V1aR mRNA was significantly greater in TGR than in SD rats. V2R mRNA expression was similar in the renal cortex and renal medulla of both strains. V1aR mRNA was well expressed in the heart of SD and TGR rats, however there was no significant difference between these two strains. V2R mRNA was not present in the heart. V1bR mRNa could not be detected either in the kidney or in the heart. The results provide evidence for specific increase of expression of V1a receptors mRNA in the renal medulla of TGR rats.
Subject(s)
Hypertension/metabolism , Kidney/metabolism , Myocardium/metabolism , RNA, Messenger/metabolism , Receptors, Vasopressin/genetics , Renin/metabolism , Animals , Animals, Genetically Modified/genetics , Rats , Rats, Sprague-Dawley , Reference Values , Renin/geneticsABSTRACT
More than half a century after the fundamental, spherical shell structure in nuclei had been established, theoretical predictions indicated that the shell gaps comparable or even stronger than those at spherical shapes may exist. Group-theoretical analysis supported by realistic mean-field calculations indicate that the corresponding nuclei are characterized by the TD(d) ("double-tetrahedral") symmetry group. Strong shell-gap structure is enhanced by the existence of the four-dimensional irreducible representations of TD(d); it can be seen as a geometrical effect that does not depend on a particular realization of the mean field. Possibilities of discovering the TD(d) symmetry in experiment are discussed.
