Fig. 5. The effect of the D2-selective agonists apomorphine and bromocriptine on albumen gland cAMP production. All agents were applied to albumen glands at a concentration of 10 µmol l^-1 for 10 min. (A) Apomorphine (APO) had no effect on basal cAMP production when compared with control glands (CON) but, surprisingly, it suppressed dopamine-stimulated cAMP production (^*P<0.05, ^**P<0.001, Tukey test). (B) Bromocriptine (BR) had no effect on either basal or dopamine-stimulated cAMP production. Bars represent the mean ± S.E.M. of 5–6 samples.