Prokineticin-2 and ghrelin robustly influence the sexual and ingestive behaviors of female Syrian hamsters

Prokineticins are involved in many physiological processes including circadian rhythms, neurogenesis, angiogenesis, and cancer. Recently, they have been found to play a role in regulating food intake. Historically, proteins that increase feeding behavior in mammals decrease reproductive behavior to prevent pregnancy and lactation when food is scarce. In the current study, prokineticin-2 (PK2) had pronounced effects on reproductive and ingestive behaviors when given to female Syrian hamsters. Administration of PK2 prevented ingestive behaviors induced by food restriction, such as the amount of time spent with food and eating. Hamsters given PK2 preferred to engage in reproductive behaviors, including spending time with a male and lordosis. Furthermore, analysis of blood plasma revealed that changes to behavior persisted despite similar levels of des-acyl ghrelin (DAG) and reduced glucose concentrations in the blood. Additionally, administering 10 mg/kg of acyl ghrelin (AG) to a different cohort of animals significantly decreased the amount of time females spent with a potential mating partner, increased the amount of time females spent with food, decreased the duration of lordosis, and increased the duration of eating. Results from the current study support the need for further research investigating the reproductive and ingestive roles of PK2 and ghrelin.