Prolactin releasing peptide (PrRP): an endogenous regulator of cell growth.
Prolactin releasing peptide (PrRP) was originally reported to act in the anterior lobe of the pituitary gland to stimulate prolactin (PRL) release; however, numerous other pharmacologic actions of PrRP have been described. In the central nervous system PrRP inhibits food intake, stimulates sympathetic tone, and activates stress hormone secretion. Here, we confirm the presence of immunoreactive PrRP in a pheochromocytoma-derived cell line (PC-12) and the ability of exogenous PrRP to stimulate adenylyl cyclase activity in these cultures. Our novel findings are that PrRP stimulated PC-12 cell growth. Furthermore, a role for endogenous PrRP in PC-12 cell growth is suggested by our observations that antisense oligonucleotides and small interfering RNA molecules, which decrease peptide content in these cells, also decrease thymidine incorporation, suggesting an autocrine action of the peptide.
Samson
Willis K
WK
Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, MO 63104, USA. samsonwk@slu.edu
Taylor
Meghan M
MM
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D016716:PC12 Cells; D034741:RNA, Small Interfering / Q000494:pharmacology; D051381:Rats; D013936:Thymidine / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology*
D016376:Oligonucleotides, Antisense; D034741:RNA, Small Interfering; D013973:Thyrotropin-Releasing Hormone; D000262:Adenylyl Cyclases; D013936:Thymidine