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The effect of cerebral ischemia on the hypophisis thyrotropic cells of gerbil

Jovan Traparić
Regionalni centar za talente Beograd 2, jovan.traparic@gmail.com

Introduction

Cerebral ischemia is a condition that occurs when there is
insufficient blood flow to the brain. As such it can cause a
stroke, in other words it can terminate the functionality of
particular clusters of nerve cells. Cerebral ischemia can be
focal, when there is damage only in a specific brain region, A B C
or global, when the whole brain does not receive sufficient Figure 1.Immuno-tagged adenohypophysis TSH cells. A –
blood flow, which also means decreased blood flow to the control; B – 7 days after ischemia; C – 14 days after
hypophisis. Cerebral ischemia leads to a number of various ischemia
hemodynamic, biochemical, and neurophysiologic changes.
The aim of this study was to test if global cerebral ischemia
(GCI) has effect on the hypophisistireotropic cells (TSH) of
gerbil (Meriones unguiculatus).

Material and methods

In the research were used 55-60 g, 3 month old male
Mongolian gerbils. The global cerebral ischemia is caused
by a 10 minute occlusion of both carotid arteries. The effect
of GCI on the pituitary TSH cells is measured 7 and 14
days after inducing GCI. Cross sections of the Figure 2.The volume density of TSH positive cells in the
adenohypophysis are made and TSH cells are dyed adenohypophysis
immunohistochemically, with anti –TSH primary and
secondary antibodies (visualized by staining reaction using
horseradish peroxidise) to determine the volume density of Conclusion
TSH cells. Stereological methods allowed for the
determination of volume density as the parameter that Global cerebral ischemia affects the functionality of basic
presents the percentage of TSH cells in the observed homeostasis maintaining systems and thus it likely affects
structure. After 7 and 14 days the volume density of the the functions of hypophisis. There is insufficient
animals with (GCI) was compared to the volume density of information in literature on the effect of ischemia on
the control group (animals without caused GCI). pituitary thyrotropic cells, although a disorder in the
regulation of thyroid hormones could have a great effect on
the healing process after ischemia. Our results show that 7
Results and 14 days after ischemia the volume density of TSH cells

is unchanged. However, there is a change and an increase in
Hypophisis TSH cells are localized mostly medioventrally basic morphological characteristics of the analyzed cells.
in the distal part of the hypophisis in a small groups or as
individual cells (Figure 1A). A great cytoplasmic
imunopositivity is noticed in these cells. They are Literature
polygonal or oval shaped with nuclei that are eccentrically
placed within the cytoplasm. 7 and 14 days after the [1] Snežana Z. Rauš, Uticaj elektromagnetnog polja
ischemia, TSH cells are in higher count while the (0,5mT, 50Hz) na motorno ponašanje, parametre
granulation of the cytoplasm is seen in cells observed 14 oksidativnog stresa i morfološke karakteristike mozga
days after ischemia (Figure 1B and 1C). In comparison with nakon eksperimentalno izazvane moždane ishemije na
modelu pustinjskog miša, Biološki fakultet Univerziteta u
the control group, the animals on which the GCI effect was Beogradu 2012
tested show no statistically significant change in the volume [2] V. Petrović, G. Cvijić, Endokrinologija opšta i
density of TSH cells. The results show an increasing trend uporedna, Zavod za udžbenike i nastavna sredstva Beograd
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days of ischemia (Figure 2). nastavna sredstva Beograd 1991.