Histological observation of Langerhans islet and beta cells of pancreas:
The rats were sacrificed at the end of the treatment.
The pancreas of control and treated groups were removed and fixed with 4% paraformaldehyde in phosphate buffer for 24 h.
The tissues were embedded in paraffin and cut into pieces of desired size (4 μm).
The sections were then deparaffinized in xylene and dehydrated a series of alcohol concentrations.
The sections were then stained with hematoxylin and eosin (H and E), or 0.1% Victoria blue (pH 0.3) to evaluate the Langerhans islet and beta cells of pancreas.
The slides were cleared in xylene and mounted with mounting medium and examined under the light microscope (Olympus BX51, Japan).
Pancreatic beta cells were identified and detected in each section for semiquantitative analysis.
The detection was performed with a X 40 objective, a X 10 eyepiece and the area observation was randomly photographed four times.
The beta cells density per tissue area in each photograph was counted and presented as a percentage of control.