Intracellular communications

Various findings together suggest that organotins may have an effect at the level of the cell membrane and/or cytoskeleton, resulting in disturbances of inter-and intracellular communication processes, which are of crucial importance to thymocyte maturation (Pieters et al., 1994a). 

Section V deals with aspects of extracellular and intracellular communication. Topics covered include membrane structure and function, the molecular bases of the actions of hormones, and the key field of signal transduction. 

Ozone attacks the rings of PAHs rather indiscriminately with fission of the rings to prodnce aldehyde gronps. There has been concern, however, since the products may be more harmful than their precursors. In the studies that are used as illustration, in vitro gap junctional intracellular communication (GJIC) was used to assess adverse alteration on the expression of genes at the transcription, translational, or posttranslational level ... 

Metofluthrin (I) The committee determined that the new data were sufficient to support a mitogenic mode of action for the development of liver tumors in rats exposed to metofluthrin in the carcinogenicity study. The report summarized mode of action study data that characterized effects such as increased P450 enzyme levels, increased smooth endoplasmic reticulum, hepatocellular hypertrophy, hepatocellular proliferation, and inhibition of intracellular communication, which were described as steps leading to tumor development via a nongenotoxic mechanism (i.e., mitogenicity). Some of these studies used sodium phenobarbital as a positive control,... 

McLean BG, Hempel FD, Zambryski PC. Plant intracellular communication via plasmodesmata. The Plant Cell 1997 9 1043-1054. 

Intracellular communication often proceeds in a pulsatile, rhythmic manner [126]. Moreover, an increasing number of hormones are found to be secreted in a pulsatile manner, and the physiological efficiency of these signals appears to be closely related to their frequency [126]. Based on this understanding, a number of classes of drug therapies have been shown to require a periodic, pulsatile regimen of delivery for efficacy or optimization [131], and several delivery strategies have been proposed to respond to this need [127-131]. 

Processing of stimuli in the nerve system includes intracellular communication, in the form of stimulus conduction in the nerve, and intercellular communication that takes place at the synapses. Synapses are specialized cell contacts used by nerve cells to communicate with one another or with other cells, e.g. muscle or sensory cells. 

Chaumontet, C. et al., Apigenin and tangeretin enhance gap junctional intracellular communication in rat liver epithelial eells, Carcinogenesis, 15, 2325, 1994. 

The cell has other transmembrane receptors and signaling pathways that do not fit into the classical receptor types and signal mechanisms described in Chapters 5-11. The following signaling pathways certainly do not complete the list of intercellular and intracellular communication mechanisms in mammals, and it is to be expected that other classes of signaling pathways will be described in the future. 

Calcium is the third most abundant metal (after Fe and Al) in the earth s crust and the fifth most abundant element in the body (after H, O, C, and N). Of all metal ions calcium, Ca, is undoubtedly most often referred to in the biochemical literature. The Ca ion plays a vital role in many processes in living systems including muscle contraction exocytosis cell fusion, adhesion, growth and motility blood cotting microtubule formation nerve excitability membrane transport of molecules intracellular communication hormonal responses biomineralization of bone and teeth photosynthesis immune reactions and enzymatic activation and control. A number of reviews and monographs are available " . 

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