Abstract
Simultaneous identification of two types of secretory
cells in the sheep pituitary gland was performed
using an image analysis system. Serial
sections were immunostained in the order of the
following hormones: ACTH, PRL, TSH, GH, and
LHβ. The image analysis system could assign different
pseudocolors to different types of immunolabelled
cells and make a montage from the two
images of the respective types of cells. The area,
number, and proportions of each cell type were
determined in two fields per tissue section. Subsequently,
the topographical relationships between
the different cell types were also analyzed. The area
of the TSH-immunolabelled cells was significantly
smaller (p ‹ 0.05) in the rostral field than in the
caudal one, while the number of cells was significantly
larger (p ‹ 0.05) in the rostral field. No striking
differences could be seen in the proportions of
the PRL-, GH-, and LHβ-immunolabelled cells between
the rostral and caudal fields. Both number
and area were largest in the PRL-immunolabelled
cells, followed by the GH cells. The ACTH, TSH,
and LHβ cells showed roughly the same low percentages.
The cell types showed a high probability
of adjoining other types in the PRL-, GH-immunolabelled
cells because of their higher numbers
and larger areas. There was no specific topographical
relationship in the present combination of
cell types.
