The effect of type 2 diabetes on the olfactory bulb structure of Wistar rats

Authors

1 Department of Biology, School of Sciences, Golestan University, Gorgan, Iran

2 Department of Physiology, Neuroscience Research Center, Golestan University of Medical Science, Gorgan, Iran

Abstract
Olfaction, the sense of smell, plays an important role in the individual's safety, nutrition, social interactions, sexual function, and quality of life. Diabetes mellitus, which affects more than 400 million people worldwide, is associated with olfactory dysfunction. This work evaluated the olfactory bulb structure of Type 2 diabetes rats. Type 2 diabetes induction was performed by administering 20mg/Kg Streptozotocin to adult Wistar rats for five days. 35 days after injection, animals were sacrificed, and olfactory bulb tissue was harvested for tissue processing and Nissl staining to evaluate the olfactory bulb structure. Based on the results, diabetic animals showed a significant decrease in the Glomeruli number compared to controls (P<0.05). Furthermore, we observed a significant decrease in the internal plexiform layer thickness in the olfactory bulb of diabetic rats when compared to controls (P<0.05). The present results showed that olfactory dysfunction in Type 2 diabetes rats is associated with olfactory bulb structural change, which indicates the olfactory bulb tissue damage caused by diabetes.


Keywords


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  • Receive Date 08 June 2026
  • Publish Date 08 June 2026