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The hypersecreting somatotroph: functional and morphological aspects

  • A. Spada
  • M. Bassetti
  • M. Arosio
  • L. Vallar
  • F. R. Elahi
  • G. Giannattasio

Abstract

Patients with acromegaly often show peculiar alterations of the GH secretory pattern. In particular, alterations in the sensitivity to physiological releasing (GHRH) or inhibiting (SRJF) hormones, together with abnormal responsiveness to hypothalamic agents such as dopamine (DA) and TRH or GnRH, are frequently observed in this disease. Cosecretion of pituitary hormones other than GH, such as prolactin, glycoprotein α-subunit, and TSH, may also occur. However, the underlying biochemical events and morphological correlates have not so far been extensively investigated. This prompted us to investigate the following aspects:
  • — Alterations of receptor regulation

  • — Alterations of postreceptor “coupling” processes

  • — Transmembrane signaling pathology

  • — Colocalization of different hormones in the same cell

Keywords

Growth Hormone Pituitary Adenoma Adenylate Cyclase Activity Acromegalic Patient Intracellular cAMP Level 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • A. Spada
    • 1
  • M. Bassetti
    • 2
  • M. Arosio
    • 1
  • L. Vallar
    • 2
  • F. R. Elahi
    • 2
  • G. Giannattasio
    • 2
  1. 1.Department of Endocrinology, School of MedicineUniversity of MilanMilanItaly
  2. 2.CNR Center of Cytopharmacology, Department of PharmacologyUniversity of MilanMilanItaly

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