Insular claustrum of the dog--a morphometric investigation of cellular structure.

Investigation of the dog's insular claustrum was performed using morphometric methods. The brains of 14 dogs (7-14 year-old) were studied. The size, shape and density of neurons are different in various parts of the insular claustrum. The posterior part, related to the visual system, is heterogenous and possesses medium-sized and small densely packed neurons, the average cross-sectional area of cell body being 175.8 +/- 45.5 micron2. The similar average cross-sectional area of cell body (174.1 +/- 55.3 micron2) was found in the central part of the insular claustrum. However, neuronal architecture is here less heterogenous and neurons are less densely arranged. The anterior part, connected mainly with the frontal and motor cortex, is more homogenous and contains loosely arranged neurons of a rather large size (average size--198.7 +/- 53.46 micron2).