During pregnancy, pancreatic islets undergo structural and functional changes in response to an increased demand for insulin. Different hormones, especially placental lactogens, mediate these adaptive changes. @entity3695 (PRL) mainly exerts its biological effects by activation of the @entity13720 / @entity27576 pathway. PRL also stimulates some biological effects via activation of @entity24577 , @entity25251 , PI 3-kinase, and MAPK in different cell lines. Since @entity25251 is important for the maintenance of pancreatic islet cell mass, we investigated whether PRL affects insulin-signaling pathways in neonatal @entity35 islets. PRL significantly potentiated @entity413 -induced insulin secretion in islets cultured for 7 days. This effect was blocked by the specific PI 3-kinase inhibitor @entity2307 . To determine possible effects of PRL on insulin-signaling pathways, fresh islets were incubated with or without the hormone for 5 or 15 min. Immunoprecipitation and immunoblotting with specific antibodies showed that PRL induced a dose-dependent @entity24577 and @entity25251 phosphorylation compared to control islets. PRL-induced increase in @entity24577 /-2 phosphorylation was accompanied by an increase in the association with and activation of PI 3-kinase. PRL-induced @entity25251 phosphorylation and its association with PI 3-kinase did not add to the effect of insulin. PRL also induced @entity13720 , SHC, @entity10861 and @entity31706 phosphorylation in neonatal islets, demonstrating that PRL can activate MAPK. These data indicate that PRL can stimulate the IRSs/PI 3-kinase and SHC/ @entity2509 pathways in islets from neonatal @entity35 .

XXXX -signal transduction in neonatal @entity35 pancreatic islets and interaction with the insulin-signaling pathway.

@entity25251 :: ('29376(Tax:10116)', 'Gene') :: ['IRS-2'] @entity10861 :: ('50689(Tax:10116)', 'Gene') :: ['ERK1'] @entity2509 :: ('24338(Tax:10116)', 'Gene') :: ['ERK'] @entity2307 :: ('MESH:C009687', 'Chemical') :: ['wortmannin'] @entity3695 :: ('24683(Tax:10116)', 'Gene') :: ['Prolactin'] @entity27576 :: ('24918(Tax:10116)', 'Gene') :: ['STAT5'] @entity13720 :: ('24514(Tax:10116)', 'Gene') :: ['JAK2'] @entity35 :: ('10116', 'Species') :: ['rat', 'rats'] @entity31706 :: ('116590(Tax:10116)', 'Gene') :: ['ERK2'] @entity24577 :: ('25467(Tax:10116)', 'Gene') :: ['IRS-1'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose']
@entity3695 :: (24683(Tax:10116),Gene) :: ['Prolactin']
