ANALYSIS OF CENTRAL VIP BINDING-SITES IN THE BREEDING AND NON-BREEDING DOVE - EFFECT OF INTRACEREBROVENTRICULAR ANTI-VIP SERUM AND VIP ANTAGONIST UPON INCUBATION BEHAVIOR

Quantitative image analysis combined with autoradiography was used to localise the distribution of VIP binding sites in the brain of the rin g dove, both with respect to sex and reproductive condition. VIP bindi ng sites were distributed extensively throughout the dove brain, and t heir distribution was similar in males and females. 47 discrete brain regions were identified as possessing either high, moderate or low bin ding intensity for VIP. In the majority of cases, the amount of bindin g was significantly (P<0.05) greater in the male compared to the femal e. In contrast, there were no significant differences observed in VIP binding between non-breeding and late incubating doves, although one a rea, the tuberal hypothalamus demonstrated a trend towards greater VIP binding in late incubating birds. Intracerebroventricular administrat ion of either anti-VIP serum or a specific VIP antagonist failed to in terrupt incubation behaviour or prevent re-nesting following nest depr ivation. These results are consistent with VIP binding sites being inv olved in numerous central actions, including a possible effect on the VIP pathway of prolactin release. However, it does not appear to play a direct role upon the expression of incubatory behaviour in this spec ies.