European Journal of Anatomy

Official Journal of The Spanish Society of Anatomy
Cover Volume 7 - Number 2
Eur J Anat, 7 (2): 91-95 (2003)

Increases in the size, number and proliferation rate of VIP-immunoreactive pituitary cells induced in vitro by TRH are associated with increases in VIP release

Carretero J., Torres J.L., Rubio M., Burks D.J., Sierra E., Angoso M., Blanco E., Herrero J., Vazquez R.

Dept. of Human Anatomy and Histology, Inst. of Neurosci. of Castilla/Leon, University of Salamanca, Spain; Depto. de Anat. e Histologia Humanas, Lab. Neuroendocrinologia INCYL, Facultad de Medicina, Avda. Alfonso X el Sabio s/n, E-37007 Salamanca, Spain

ABSTRACT Pituitary VIP levels and pituitary VIP-expressing cell numbers are increased in hypothyroidism, but the regulating role of TRH as regards morphological changes remains obscure. In order to determine whether TRH is involved in regulating the maintenance of pituitary VIP-expressing cells and its cellular proliferation a double immunocytochemical study for VIP and proliferating cell nuclear antigen (PCNA) was carried out in pituitary monolayer cultures treated with TRH. TRH induced a significant in vitro increase in the numerical density (p<0.01) and percentage (p<0.001) of VIP-expressing cells. These changes were accompanied by increases in VIP release (p<0.01) and in the size (p<0.01) of VIP-expressing cells. Our results suggest that TRH could regulate the maintenance of the percentage of pituitary VIP-expressing cells, their activity and their proliferation in a similar way to the way in which it regulates the release of VIP.

Keywords: cycline, protirelin, vasoactive intestinal polypeptide, animal cell, article, cell count, cell density, cell proliferation, cell size, hormonal regulation, hormone release, hypophysis cell, hypothyroidism, immunocytochemistry, male, neurosecretory cell, nonhuman, protein expression, rat

European Journal of anatomy
ISSN 2340-311X (Online)