The Histochemical Journal

, Volume 32, Issue 9, pp 565–569 | Cite as

Effect of Centrally Administered Somatostatin on Pituitary Thyrotropes in Male Rats

  • Verica Milošević
  • Milka Sekulić
  • Branislava Brkić
  • Mirjana Lovren
  • Vesna Starčević
Article

Abstract

The effects of intracerebroventricularly administered somatostatin (SRIH-14 or -28) on growth and function of pituitary thyrotropes (TSH-cells) were examined in adult male Wistar rats. The animals were implanted with an intracerebroventricular cannula and after a recovery period, administered three 1 μg doses of SRIH-14 or -28 dissolved in 5 μl saline every second day. Controls were treated in the same way with the same volume of saline only. TSH-producing cells were studied using the peroxidase–antiperoxidase immunohistochemical procedure. Blood samples were collected for hormone (TSH) analyses 5 days after the last injection. Both SRIH-treatments significantly decreased (p < 0.05) all morphometric parameters obtained for TSH-cells in comparison with controls. The volume of TSH-cells decreased by 27%, nuclei by 44% and volume density by 33% in animals treated with SRIH-14. In animals treated with SRIH-28, these parameters were also significantly decreased (p < 0.05) (22%, 31%, and 25% respectively) compared to control rats. Serum concentrations of TSH were significantly decreased (p < 0.05) by 15% in SRIH-14- and by 12% in SRIH-28-treated animals in comparison with the controls. These observations suggest that centrally administered SRIH-14 or -28 is specifically involved in the control of growth and secretory activity of TSH cells.

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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Verica Milošević
    • 1
  • Milka Sekulić
    • 1
  • Branislava Brkić
    • 2
  • Mirjana Lovren
    • 1
  • Vesna Starčević
    • 3
  1. 1.Department of CytologyInstitute for Biological Research ‘Siniša Stanković’Yugoslavia
  2. 2.Clinical Centre';BelgradeYugoslavia
  3. 3.Institute of Physiology, School of MedicineUniversity of BelgradeBelgradeYugoslavia

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