Congenital nephrogenic diabetes insipidus arginine vasopressin receptor 2 gene mutation at new site:A case report

BACKGROUND Congenital nephrogenic diabetes insipidus(CNDI)is a rare hereditary disorder.It is associated with mutations in the arginine vasopressin receptor 2(AVPR2)gene and aquaporin 2(AQP2)gene,and approximately 270 different mutation sites have been reported for AVPR2.Therefore,new mutations and new manifestations are crucial to complement the clinical deficiencies in the diagnosis of this disease.We report a case of a novel AVPR2 gene mutation locus and a new clinical manifestation.CASE SUMMARY We describe the case of a 48-d-old boy who presented with recurrent fever and diarrhea 5 d after birth.Laboratory tests showed electrolyte disturbances and low urine specific gravity,and imaging tests showed no abnormalities.Genetic testing revealed a novel X-linked recessive missense mutation,c.283(exon 2)C>T(p.P95S).This mutation results in the substitution of a proline residue with a serine residue in the AVPR2 protein sequence.The diagnosis of CNDI was confirmed based on the AVPR2 gene mutation.The treatment strategy for this patient was divided into two stages,including physical cooling supplemented with appropriate amounts of water in the early stage and oral hydrochlorothiazide(1-2 mg/kg)after a clear diagnosis.After follow-up of one and a half years,the patient gradually improved.CONCLUSION AVPR2 gene mutations in new loci and new clinical symptoms help clinicians understand this disease and shorten the diagnosis cycle.

Synthesis and biological evaluation of novel phenothiazine derivatives as non-peptide arginine vasopressin V2 receptor antagonists

A series of novel phenothiazine derivatives was synthesized and tested for arginine vasopressin receptor antagonist activity. They were synthesized as novel arginine vasopressin receptor antagonists from phenothiazine as a scaffold via successive acylation, reduction and acylation reactions. Their structures were characterized by ^1H NMR, ^13C NMR and HRMS, and biological activity was evaluated by in vitro and in vivo studies. The in vitro binding assay indicated that several compounds are potent selective V2 receptor antagonists. Compounds with promising binding affinity to V2 receptors were selected to conduct the in vivo diuretic studies on Sprague-Dawley rats. Among them, 1n, 1r, It and 1v exhibited excellent diuretic activity, especially 1 r and 1v. Therefore, 1 r and 1v are potent novel AVP V2 receptor antagonist candidates.

Synthesis and biological evaluation of novel derivatives of desloratadine

Series of novel derivatives of desloratadine designed as arginine vasopressin receptor antagonists were synthesized and structurally characterized by melting points,^1H NMR and HRMS.Their in vivo diuretic activities were evaluated on rats,and several target compounds showed promising diuretic results, especially compounds 8,18,27 and 31.Further in vitro bonding assay and cAMP assay showed that these compounds had a higher affinity to vasopressin V2 receptor than VI a receptor.Our studies indicated that desloratadine may be an active substructure for novel arginine vasopressin receptor antagonist development.