Table 3. KEGG pathway analysis of differentially expressed genes.

Expression	Pathway	Gene count	Adjust P value
Up-regulated	hsa04080: Neuroactive ligand–receptor interaction	33	7.78E−07
	hsa04974: Protein digestion and absorption	15	3.53E−05
	hsa04972: Pancreatic secretion	15	6.62E−05
	hsa04610: Complement and coagulation cascades	11	9.91E−04
	hsa04970: Salivary secretion	12	0.002
	hsa04512: ECM-receptor interaction	12	0.002
	hsa05033: Nicotine addiction	8	0.002
	hsa04514: Cell adhesion molecules (CAMs)	15	0.005
	hsa05032: Morphine addiction	11	0.008
Down-regulated	hsa04610: Complement and coagulation cascades	6	8.62E−04
	hsa00982: Drug metabolism—cytochrome P450	5	0.006

Notes.

P value < 0.01 was considered as threshold values of significant difference.