Gap junction intercellular communication GJIC

Baker, T.K., Kalimi, G.H., Lington, A.W., Isenberg, J.S., Klaunig, J.E. Nikiforov, A.I. (1996) Gap junctional intercellular communication (GJIC) studies on 5 phthalate monoesters in hepatocytes of four species implications for cancer risk assessment (Abstract). Toxicologist, 30, 208... 

Isenberg JS, Kamendulis LM, Smith JH, et al. 2000. Effects of Di-2-Ethlhexyl phthalate (DEHP) on gap-junctional intercellular communication (GJIC), DNA synthesis, and peroxisomal beta oxidation (PBOX) inrat, mouse, and hamster liver. Toxicol Sci 56 73-85. 

The following sections provide an in-depth analysis of the proposed MOA for rat and mouse liver tumors induced by PPARa activators. This analysis is not intended to reflect an exhaustive review of the literature but rather a sununation of key evidence. This review of the data did not consider alternative effects of PPARa activators, including mitochondrial effects, gap junction intercellular communication (GJIC), or methylation of DNA, because the data are weak or a direct causal link to liver tumor induction is lacking. 

GJIC, gap junctional intercellular communication RTECS, Registry of Toxic Effects of Chemical Substances. 

Figure 7 Utility of the scrape loading/dye transfer assay to detect a toxin/toxicant s ability to modulate gap junctional intercellular communication. The last two images (6ngmr TPA) illustrate both the epifluorescent and phase images, respectively, of the same cells to show that the complete inhibition of GJIC was not associated with the death of cells.

In summary, GJIC enables cells to rapidly share critical ions and molecules that influence whether cells remain active, proliferate, differentiate, commit apoptosis, or adapt in response to external stimuli. In addition to effects on individual cells, this form of intercellular communication synchronizes the activities of cells within a tissue. Thus, when gap junctions are altered in inappropriate ways by endogenous or exogenous factors or conditions, a variety of toxic outcomes and diseases may result. 

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