title: Connexin 36 is expressed in beta and connexins 26 and 32 in acinar cells at the end of the secondary transition of mouse pancreatic development and increase during fetal and perinatal life.
abstract: To identify when during fetal development connexins (Cxs) 26 (Cx26) 32 (Cx32), and 36 (Cx36) begin to be expressed, as well as to characterize their spatial distribution, real time polymerase chain reaction and immunolabeling studies were performed. Total RNA from mouse pancreases at 13 and 18 days postcoitum (dpc) and 3 days postpartum (dpp) was analyzed. In addition, pancreatic sections of mouse at 13, 14, 15, 16, 18 dpc and 3 dpp and of rat at term were double labeled with either anti-insulin or anti-α-amylase and anti-Cx26 or -Cx32 or -Cx36 antibodies and studied with confocal microscopy. From day 13 dpc, Cxs 26, 32, and 36 transcripts were identified and their levels increased with age. At 13-14 dpc, Cxs 26 and 32 were localized in few acinar cells, whereas Cx36 was distributed in small beta cell clumps. From day 14 dpc onwards, the number of labeled cells and relative immunofluorescent reactivity of all three Cxs at junctional membranes of the respective cell types increased. Cxs 26 and 32 colocalized in fetal acinar cells. In rat pancreas at term, a similar connexin distribution was found. Relative Cxs levels evaluated by immunoblotting also increased (two-fold) in pancreas homogenates from day 18 dpc to 3 dpp. The early cell specific, wide distribution, and age dependent expression of Cxs 26, 32, and 36 during fetal pancreas ontogeny suggests their possible involvement in pancreas differentiation and prenatal maturation.
authors.affiliation: Departamento de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, México, DF, México. mperezarmendariz@aol.com
authors.forename: Elia Martha
authors.initials: EM
authors.lastname: Pérez-Armendariz
authors.forename: Lourdes
authors.initials: L
authors.lastname: Cruz-Miguel
authors.forename: Cristina
authors.initials: C
authors.lastname: Coronel-Cruz
authors.forename: Marcelino
authors.initials: M
authors.lastname: Esparza-Aguilar
authors.forename: Enrique
authors.initials: E
authors.lastname: Pinzon-Estrada
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Rancaño-Camacho
authors.forename: Gerardo
authors.initials: G
authors.lastname: Zacarias-Climaco
authors.forename: Paola Fernández
authors.initials: PF
authors.lastname: Olivares
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Espinosa
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Becker
authors.forename: Juan C
authors.initials: JC
authors.lastname: Sáez
authors.forename: Jaime
authors.initials: J
authors.lastname: Berumen
authors.forename: Gregorio
authors.initials: G
authors.lastname: Pérez-Palacios
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005333:Fetus / Q000196:embryology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010179:Pancreas / Q000196:embryology* / Q000254:growth & development* / Q000378:metabolism; D046790:Pancreas, Exocrine / Q000378:metabolism*; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction; D000097002:Gap Junction beta-1 Protein; D000097004:Gap Junction delta-2 Protein
chemical_list: D000072259:Connexin 26; D017630:Connexins; D000097002:Gap Junction beta-1 Protein; D000097004:Gap Junction delta-2 Protein; C000607044:Gjb2 protein, rat