Immunohistochemical expression of nestin in adenohypophysial vessels during development of pituitary infarction.
OBJECTIVE
The aim of this work was to investigate the immunohistochemical expression of nestin, a member of the intermediate filament family, in adenohypophysial vasculature during development and progression of pituitary infarction.


METHODS
Forty-five nontumorous adenohypophyses and 34 pituitary adenomas of various types, all exhibiting acute or healing infarcts, were examined immunohistochemically using the streptavidin-biotin-peroxidase complex method.


RESULTS
In both adenohypophyses and pituitary adenomas without infarction, nestin was expressed in only a few capillaries and endothelial cells. In acute infarcts without a vascular response, no nestin was demonstrable within necrotic capillaries (50 cases). In organizing infarcts, newly formed vessels spreading into necrotic zones showed nestin expression in all capillaries and practically every endothelial cell (25 cases). In the hypocellular, fibrotic scar phase, only a few vessels (4) were apparent, and immunoreactivity was focal and mild.


CONCLUSIONS
Nestin is strongly expressed in newly formed capillaries and is downregulated when infarcts transform to fibrous tissue. Nestin expression may provide valuable insight into the process of pituitary angiogenesis.
Salehi
Fateme
F
Department of Laboratory Medicine, St. Michael's Hospital, University of Toronto, Ontario, Canada.
Kovacs
Kalman
K
Cusimano
Michael D
MD
Horvath
Eva
E
Bell
C David
CD
Rotondo
Fabio
F
Scheithauer
Bernd W
BW
D000236:Adenoma / Q000378:metabolism* / Q000473:pathology; D002196:Capillaries / Q000378:metabolism; D016022:Case-Control Studies; D042783:Endothelial Cells / Q000378:metabolism; D006801:Humans; D007238:Infarction / Q000378:metabolism* / Q000473:pathology; D007381:Intermediate Filament Proteins / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D064231:Nestin; D010899:Pituitary Apoplexy / Q000378:metabolism* / Q000473:pathology; D010903:Pituitary Gland, Anterior / Q000098:blood supply* / Q000378:metabolism; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000473:pathology
D007381:Intermediate Filament Proteins; C577484:NES protein, human; D009419:Nerve Tissue Proteins; D064231:Nestin