Effects of t-TUCB and Rolipram on TS exposure–induced mucin production. (A) Sections of the bronchial wall from filtered air (Control), TS-exposed SH rats with vehicle treatment (TS vehicle), sEHI treatment (TS sEHI), or Rolipram treatment (TS Rolipram) stained with alcian blue/periodic acid–Schiff for the detection of mucous glycoconjugate. (B) Blinded quantification of intraepithelial mucosubstances. *P < 0.05, TS-exposed groups were significantly different from the control group. ‡P < 0.05, treatment group with Rolipram was significantly different from the TS vehicle group.