CHRONIC EXPERIMENTAL DIABETES MELLITUS

QUANTITATIVE CHANGES IN DORSAL ROOT GANGLION CELLS

Abstract

Background: Multiple factors operate in the development of diabetic neuropathy.
Sensory neurons are not protected by blood-brain or blood-nerve barrier; also the dorsal root
ganglion cells (DRG) have a higher metabolic requirement than the nerve trunks. Oxygen level
at the dorsal root ganglions also appears to be lower. All these physiological characteristics
suggest that DRG may be particularly susceptible to damage in prolonged diabetic conditions.
Objectives: To observe the quantitative cellular changes in dorsal root ganglion cells in rats with
prolonged experimental diabetes. Study Design: An experimental study. Setting: Department
of Human Anatomy, Faculty of Medicine, Umm al Qura University, Makkah, Saudi Arabia.
Period: Fifteen months to complete. Material and methods: Observations were made on six
control and six streptozotocin-treated male Sprague-Dawley rats after 12 months of diabetes.
Cell count was done on silver-stained paraffin sections. DRG cells were arbitrarily grouped
as large A-type and small B-type. Statistical examination of the cell count was done using a
two-tailed t-test. Values were considered significant at P ≤ 0.05. Results: In the control group
of animals the mean total number was 15856.33 ± 552.538 while in the diabetic animals it
was 11836.666 ±583.177; the reduction in the number of cells was significant. The number of
A-type and B-type cells and their percentages in the control group and the diabetic group of
animals were 2753.833±257.683 (17.36%), 13102.5±443.092 (82.63%) and 1202.833±87.082
(10.16%), 10633.833±517.900 (89.83%) respectively. The differences in the number of A-type
and B-type of cells when compared between control and diabetic groups of animals were
statistically highly significant. Conclusion: Selective cells damage to DRG cells may be the
harbinger of diabetic neuropathy in experimentally induced diabetic rats.