stereological study on the neurons of superior cervical sympathetic ganglion in diabetic rats

background: most research on autonomic dysfunction of diabetes mellitus is conducted on ganglions innervating gastrointestinal (gi) tract and there are limited works focusing on cervical sympathetic ganglia. the effects of diabetes mellitus (dm) on the neurons of superior cervical sympathetic ganglion (scsg) are investigated by stereological methods.   material and methods: female rats (n=72) randomly divided into dm (blood glucose =400-600 mg/dl) and control (n=36) groups. rats were sacrificed at 4-, 8- and 12-weeks of induction of dm (65 mg/kg streptozotocin, ip). the same procedure followed chronologically in control group. scsg of both groups were removed, fixed, and embedded in cylindrical blocks. isotropic uniform random sections obtained and stained. the mean particle volume (according to the method of volume-weighted mean particle estimation) of the perikarya and nuclei of ganglion cells (neurons) were estimated using the point-sample intercepts method.   results: there was no significant difference between the mean perikaryal and nuclear volumes of dm and control rats after 4-, 8- and 12-weeks. there was, however, a significant increase in the mean volume of perikarya and nuclei of the neuronal cells of dm rats at 8- and 12-weeks diabetes as compared with those of 4-weeks.   conclusion: the mean volume of scsg and their nuclei were not significantly reduced after 4-, 8-and 12-weeks in dm rats and these cells continued their normal growth. iran j med sci 2005; 30(1): 24-27.   keywords ● diabetes mellitus ● stereology ● autonomic ganglia