ABSTRACT
OBJECTIVE: To analyze the impact of olfactory nerve transection on the apoptosis of mice olfactory receptor neurons (ORN), and discuss the reliability of this experimental model. METHODS: After olfactory nerve transection of mice, anterograde horseradish peroxidase (HRP) tracing was performed to confirm the completion of nerve transection. On 8 h, 2 d, 3 d and 5 d after surgery, TdT mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL) was used to observe the apoptosis of ORN, while relative semi-quantitative RT-PCR and immunohistochemistry were used to reflect the expression of olfactory marker protein (OMP, special marker of mature ORN) in olfactory epithelium. RESULTS: No HRP label was observed in olfactory bulb after olfactory nerve transaction. Both TUNEL-positive and OMP-positive cells were ORN. After the surgery, TUNEL-positive cells increased remarkably and peaked on 2 d after the surgery. Meanwhile OMP mRNA in olfactory epithelium began to decrease markedly till 5 d after the surgery, and the olfactory epithelium got thinner accordingly. CONCLUSIONS: This experimental model can be used reliably to sever mice olfactory nerve and manipulate simultaneous apoptosis of mice ORN.