Effects of fostriecin and rubratoxin A on bovine ciliary muscle strips. Fostriecin
and rubratoxin A were added to BCM strips pre-contracted by CCh or ionomycin. (a)
Following CCh-induced contraction, 3 µmol/l fostriecin did not cause any change
(97.7 ± 3.4%, n = 6, P = 0.53). (b) With
ionomycin-induced contraction, 3 µmol/l fostriecin inhibited contraction completely
(2.0 ± 1.6%, n = 6, P < 0.01). (c) Rubratoxin A
inhibited CCh-induced contraction at 10 µmol/l (1.7 ± 2.2%, n = 6,
P < 0.01). (d) It also inhibited ionomycin-induced
contraction. Three µmol/l rubratoxin A decreased ionomycin-induced tension to 63.2 ±
6.8% (n = 6, P < 0.01), and 10 µmol/l relaxed
it completely (1.5 ± 1.7%, n = 6, P <
0.01).