Arginine vasotocin effects on courtship behavior in male white perch (Morone americana).

Arginine vasotocin (AVT) and its mammalian homologue, arginine vasopressin (AVP), have been shown to have widespread behavioral effects in vertebrates. AVT was evaluated for its effectiveness in stimulating an important courtship behavior termed 'attending' in male white perch, Morone americana. Attending consists of close and continuous following of the female with occasional contact in the abdominal area. We tested the behavioral effectiveness of AVT in stimulating attending when administered either intraperitoneally (IP) or intracerebroventricularly (ICV). We also tested IP injections of AVT alone and in combination with an AVP V(1) receptor antagonist (Manning compound). None of the IP injections of either AVT or Manning compound produced consistent effects on attending behavior. In contrast, ICV injections of AVT did significantly increase attending behavior and at low dosages. Circulating levels of testosterone and 11-ketotestosterone were not affected approximately 80 min following injection by any of the treatments. The strong behavioral effects observed with ICV administration support a central site of action for AVT in stimulating attending behavior. This is a complex behavior that shows similarities to behaviors mediated by AVT and AVP in other vertebrates, providing further evidence of a conserved behavioral role for these peptides.