Fig. 3
a Representative recording showing the effects of 10−6 M VIP on 10−6 M PE pre-contracted in the presence of wortmannin (Wort) in EI rings (n = 6). b Representative recording showing the effect of 10−6 M VIP on 10−6 M PE pre-contracted in the presence of LY294002 (LY) in EI rings (n = 6). c In comparison to control, a treatment of the EI rings with either wortmannin or LY294002 produced significantly smaller relaxations. d On the other hand, treatment with wortmannin (n = 5) or LY294002 (n = 9) did not produce any significant relaxation in ED rings compared to control ED. Responses are expressed as percentage of the active tension originally generated by 10−6 M PE. Data were expressed as mean ± SE. *P < 0.05; **P < 0.01 versus control group