Different changes in expression and function of connexin 26 and connexin 32 during DNA synthesis and redifferentiation in primary rat hepatocytes using a DMSO culture system

Abstract

recovery of GJIC measured by lucifer yellow was later thanIn the present study, we determined in detail the changes that of Cx32 expression. These results indicated the different of liver gap junctions, connexin 26 (Cx26), and connexin 32 changes of expression and function of Cx26 and Cx32 in the (Cx32), during DNA synthesis and redifferentiation of hepatohepatocytes during stimulation and re-inhibition of DNA syncytes in vitro. We used primary rat hepatocytes that expressed thesis. This culture system should be useful as a model in the liver gap junction proteins, which were cultured in the which to study liver gap junctions during hepatocyte growth medium containing epidermal growth factor (EGF) with 2% and differentiation in vitro. (HEPATOLOGY 1997;26:585-597.) dimethylsulfoxide (DMSO) and 10 07 mol/L glucagon (a DMSO culture system), as we previously reported. In the present cultures, almost confluent hepatocytes cultured in the medium Gap junctions are intercellular membrane channels that containing EGF with 2% DMSO and 10 07 mol/L glucagon, link neighboring cells and mediate reciprocal exchanges of underwent a nearly synchronous wave of DNA synthesis insmall molecules of less than 1,000 Da and ions, including duced by the removal of 2% DMSO and 10 07 mol/L glucagon, second messengers, such as cyclic adenosine monophosphate and the addition of 10 mmol/L nicotinamide, after which the inositol triphosphate, and Ca 2/ , between adjacent cells in DNA synthesis was completely re-inhibited by the re-addition contact. [1][2][3][4] Gap junctions are composed of proteins termed of 2% DMSO and 10 07 mol/L glucagon. During stimulation of ''connexins (Cxs)''. 5 Both Cx26 and Cx32 are expressed in DNA synthesis, both Cx26 and Cx32 messenger RNA hepatocytes, and it is known that the relative ratios of Cx26 (mRNAs) in hepatocytes transiently increased in the G1 phase protein and messenger RNA (mRNA) in rat livers to those and then markedly decreased before the onset of the S phase, of Cx32 are 1:10 and 1:50, respectively. 6,7 The distribution while only Cx26 messenger RNA (mRNA) increased slightly of these Cx proteins is reported to be different within the in the S/M phase. Furthermore, before the onset of the S phase, liver lobules: Cx26 preferentially localizes in the periportal a disappearance of both Cx26 and Cx32 immunoreactivities zone of the lobules, whereas Cx32 appears in most hepatoand gap junction plaques were observed. Gap junctional intercytes throughout the lobules. 8,9 They have been colocalized cellular communication (GJIC), as measured by lucifer yellow, to the same gap junction plaques in hepatocytes. 6,10,11 Furwhich indicated the function of Cx32, decreased markedly from thermore, more recently, Kumar and Gilula 12 reported that before the onset of the S phase. GJIC measured by propidium gap junction channels in the mouse liver are heterotypic iodide, which indicated the function of Cx26, decreased from channels, which dock among heteromeric connexons combefore the onset of the S phase and then increas...

Three‐dimensional visualization and physiologic evaluation of bile canaliculi in the rat liver slice by confocal laser scanning microscopy

“…Gap junctions existing in the intercellular space play an important role in the intercellular signal transduction system. It was confirmed that there are two GJs in the liver (connexin 26 and 32), and connexin 32 accounts for the majority in the intralobular distribution of GJ, whereas the distribution of connexin 26 is limited to zones 1 and 2 alone (Kojima et al 1997, Neveu et al 1995, Stutenkemper et al 1992. Such differences in the distribution of GJ may induce differences in the distribution of LY dye.…”

Woodchuck hepatocytes remain permissive for hepadnavirus infection and mouse liver repopulation after cryopreservation

“…33 However, low concentrations of DMSO (1% to 2%) in the culture medium have been shown to support cell differentiation [34][35][36] and to increase infectivity of freshly isolated hepatocytes. 37 Here, we provide evidence that after stepwise reduction of DMSO, maintenance of 2% DMSO in culture not only improved attachment rates of thawed hepatocytes, but it allowed establishment of WHV infection in vitro.…”

The polarized hepatic human/rat hybrid WIF 12-1 and WIF-B cells communicate efficientlyin vitro via connexin 32-constituted gap junctions

“…19 Interestingly, one of them, AML12, stably expressed mRNAs for Cx32 and Cx26, but nothing was reported about the relative proteins and their GJIC competence. Concerning hepatocytes in primary culture, although they express Cx32 and Cx26, 20 their GJIC is usually poor and may be sligthly improved either by treatment with dimethylsulfoxide (DMSO) 20,21 or by co-culture with fibroblasts. 22 Being interested in the modulation of GJIC of hepatocytes, we tried to find an in vitro cell system that efficiently communicates via liver-specific Cxs.…”