Figure 4.

Urethane anaesthetized female rats: histograms comparing the changes (Δ) caused by i.v. injection of vehicle for L-NAME (saline) and L-NAME (20 mg kg⁻¹), and infusions of zaprinast vehicle (5% triethanolamine in saline) and zaprinast (0.6 mg kg⁻¹ min⁻¹) on (a) the amplitude and (b) the duration of reflex-evoked urethral relaxations in (A) non- and (B) α-bungarotoxin (0.4 mg kg⁻¹, i.v.) pre-treated rats. Each bar represents the mean value and vertical bars show s.e.mean. Changes caused by drugs were compared with vehicle controls using Student's unpaired t-test. ^*P<0.05 ^**P<0.01.