A cellular and molecular basis for the selective desmopressin-induced ACTH release in Cushing’s disease patients: key role of AVPR1b receptor and potential therapeutic implications

Journal of Clinical Endocrinology and Metabolism, 07/25/2013  Review Article

Luque RM et al. – The study aims to determine, for the first time, whether desmopressin acts directly and exclusively on pituitary corticotropinoma cells to stimulate ACTH expression/release, and to elucidate the cellular and molecular mechanisms involved in desmopressin–induced ACTH increase in Cushing’s disease (CD).

The present results provide a cellular and molecular basis to support the desmopressin stimulation test as a reliable, specific test for the diagnosis and post–surgery prognosis of CD.

Furthermore, the data indicates that AVPR1b is responsible of the direct/exclusive desmopressin–stimulatory pituitary effects observed in CD, thus opening the possibility of exploring AVPR1b–antagonists as potential therapeutic tools for CD treatment.

~~~~~~~~

Abstract

  1. RM Luque1,#,
  2. A Ibáñez-Costa1,#,
  3. LM López-Sánchez1,
  4. L Jiménez-Reina2,
  5. E Venegas-Moreno3,
  6. MA Gálvez4,
  7. A Villa-Osaba1,
  8. AM Madrazo-Atutxa3,
  9. MA Japón5,
  10. A de la Riva6,
  11. DA Cano3,
  12. P Benito-López4,
  13. A Soto-Moreno3,
  14. MD Gahete1,
  15. A Leal-Cerro3,*and
  16. JP Castaño1,*

Author Affiliations


  1. 1Department of Cell Biology, Physiology and Immunology University of Córdoba, Reina Sofía University Hospital, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC); CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn); 14014, Córdoba, Spain.

  2. 2Department of Morphological Sciences, University of Córdoba. Córdoba, Spain.

  3. 3Instituto de Biomedicina de Sevilla (IBiS), University Hospital Virgen del Rocío/Consejo Superior de Investigaciones Científicas/University of Seville and Endocrinology, Metabolism and Nutrition Unit, Virgen del Rocío University Hospital, Seville, Spain.

  4. 4Service of Endocrinology and Nutrition, Reina Sofía University Hospital, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC). Córdoba, Spain.

  5. 5Department of Pathology, Virgen del Rocio University Hospital, Seville, Spain.

  6. 6Service of Neurosurgery, Reina Sofía University Hospital Córdoba, Spain.
  1. Address all correspondence and requests for reprints to: Raúl M. Luque and Justo P. Castaño.Department of Cell Biology, Physiology and Immunology; Campus Universitario de Rabanales, Edificio Severo Ochoa (C6), Planta 3; University of Córdoba, E-14014 Córdoba, Spain. Phone:(34)-957218594. Fax: (34)-957218634. E-mails: raul.luque@uco.esjusto@uco.es.
  1. # These authors have codirected this study.

Abstract

Context: Desmopressin is a synthetic agonist of vasopressin-receptors (AVPRs). Desmopressin stimulation test is employed in the diagnosis and post-surgery prognosis of Cushing’s disease (CD). However, the cellular and molecular mechanisms underlying the desmopressin-induced ACTH increase in CD patients are poorly understood.

Objective: 1) To determine, for the first time, whether desmopressin acts directly and exclusively on pituitary corticotropinoma cells to stimulate ACTH expression/release, and 2) to elucidate the cellular and molecular mechanisms involved in desmopressin-induced ACTH increase in CD.

Design: 8 normal-pituitaries (NPs), 23 corticotropinomas, 14 nonfunctioning-pituitary adenomas (NFPA), 17 somatotropinomas and 3 prolactinomas were analyzed for AVPRs-expression by qrtPCR. Primary cultures derived from corticotropinomas, NFPAs, somatotropinomas, prolactinomas and NPs were treated with desmopressin and ACTH-secretion/expression, [Ca2+]i-kinetics, AVPRs-expression and/or proliferative-response were evaluated. The relationship between AVPRs-expression and plasma adrenocorticotropin/cortisol levels obtained from desmopressin-tests was assessed.

Results: Desmopressin affects all functional parameters evaluated in corticotropinoma-cells but not in NPs or other pituitary-adenomas cells. These effects might be due to the dramatic elevation of AVPR1b expression levels found in corticotropinomas. In line with this notion, the use of an AVPR1b-antagonist completely blocked desmopressin-stimulatory effects. Remarkably, only AVPR1b-expression was positively correlated with elevated plasma adrenocorticotropin levels in corticotropinomas.

The present results provide a cellular and molecular basis to support the desmopressin stimulation test as a reliable, specific test for the diagnosis and post-surgery prognosis of CD. Furthermore, our data indicates that AVPR1b is responsible of the direct/exclusive desmopressin-stimulatory pituitary effects observed in CD, thus opening the possibility of exploring AVPR1b-antagonists as potential therapeutic tools for CD treatment.

Footnotes

  • * These authors have codirected this study.

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