Amylin is a novel neuropeptide with potential maternal functions in the rat

• Published in: The FASEB journal 2012-01, Vol.26 (1), p.272-281
• Main Authors: Szabó, Éva Rebeka, Cservenák, Melinda, Dobolyi, Arpad
• Format: Article
• Language: English
• Subjects: Animals; Animals, Suckling; Behavior, Animal - physiology; Female; hypothalamus; Islet Amyloid Polypeptide - genetics; Islet Amyloid Polypeptide - metabolism; Key Words; Maternal Behavior - physiology; Maternal Deprivation; Neural Pathways - cytology; Neural Pathways - physiology; Neurons - physiology; Ovariectomy; peptide expression; Peripartum Period - physiology; postpartum mother; Postpartum Period - physiology; Pregnancy; preoptic area; Preoptic Area - cytology; Preoptic Area - physiology; Proto-Oncogene Proteins c-fos - genetics; Proto-Oncogene Proteins c-fos - metabolism; Rats; Rats, Wistar; RNA, Messenger - metabolism
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fj.11-191841

ABSTRACT Amylin, a 37‐aa pancreatic peptide, was found to be expressed in the preoptic area of mother rats in our recent microarray study. Here, we report a marked increase in amylin expression around parturition and show that amylin mRNA level remains elevated as long as the pups are not removed from the dams. Amylin expression is also induced in maternally behaving (sensitized) nonlactating but not in nonsensitized nulliparous females or in females that did not become maternal despite the sensitization procedure. Immunohistochemistry verified the increased amylin peptide expression in maternally behaving rats and demonstrated the same expression pattern of amylin as in situ hybridization histochemistry. Ovariectomy had no effect on the activation of amylin neurons, suggesting sexual steroid‐independent mechanisms. In subsequent functional experiments, mothers were separated from their pups for 22 h. On return of the pups, neuronal activation was found in the mother's preoptic area, with a distribution pattern similar to amylin‐expressing neurons. Subsequent double labeling revealed that 86‐93% of amylin neurons were activated by pup exposure. The results implicate amylin in the control of maternal adaptations, possibly exerting its actions on maternal behaviors via amylin receptors present in brain regions to which preoptic neurons project.—Szabó, E. R., Cservenák, M., Dobolyi, A. Amylin is a novel neuropeptide with potential maternal functions in the rat. FASEB J. 26, 272–281 (2012). www.fasebj.org