Morphometric study of the beta-cell volume of the canine pancreas with consideration of the axis of tissue transection.

The pancreatic beta-cell volume was assessed in 12 clinically normal crossbred dogs using immunohistochemical labelling for insulin and computer-assisted morphometric analysis. The beta-cell volume was less in the right lobe compared with the body and left lobe, but the beta-cell volume did not differ between the body and the left lobe as reported previously. The use of immunohistochemistry, computer-assisted morphometry, the inclusion here of extra-islet beta-cells and the exclusion of non-beta-endocrine cells in the investigation of the beta-cell volume may have contributed to this discrepancy. As most beta-cells form irregularly shaped three-dimensional bodies (islets of Langerhans), the effect of the plane of tissue transection (sagittal, transverse, oblique) on the calculation of the beta-cell volume was also examined. The beta-cell volume in the sagittal plane of the right lobe was lower than the volume in the oblique plane of the same lobe but was not different from the volume in the transverse plane. However, there were no differences in beta-cell volume in different planes in the body or left lobe. When quantifying beta-cell volume in health or disease, variation in the volume of beta-cells in different locations of the pancreas is an important consideration and the plane of transection may also influence results.