Permeability of a Cell Membrane Junction

Abstract

The ion permeability of the membrane junctions between Chironomus salivary gland cells is strongly depressed by treatments that are generally known to inhibit energy metabolism. These treatments include prolonged coolhag at 6°-8°C, and exposure to dinitrophenol, cyanide, oligomycin, and Nethylmaleimide. IntraceUular injection of ATP appears to prevent depression of junctional permeability by dinitrophenol or to reverse it. Ouabain, azide, pchloromercuriphenylsulfonic acid, reserpine, and acetazolamide fail to depress junctional permeability. Thus the ion permeability of the junctional membranes appears to depend on energy provided by oxidative phosphorylation. Possible energy-linked processes for maintaining junctional permeability are discussed, including processes involving transport of permeability-modifying species such as Ca ++ .

Review: Cytochemical aspects of gap junction: Enzyme activity, hydrophilic channel and charge.

“…The coupled state, however, is not stationary, and thus treatment with a metabolic inhibitor, or Ca2+ etc. causes a reversible alteration from the coupled state to the uncoupled (7,10,11,45,47). In order to correlate enzyme activity with the coupling and uncoupling of gap junctions, unfixed Microslicer sections or small blocks of cardiac muscle were preincubated in a mixture of metabolic inhibitor or uncoupler such as 10 mM dinitrophenol, 10 mM sodium propionate, 5 mM potassium cyanide and 5 mM deoxy-D-glucose in HEPES-Ringer's solution for 30 min at 37°C.…”

On Correlation between Gland Stiffness and Cell Coupling in Salivary Gland of <I>Chironomus plumosus</I> Larva

“…Loewenstein proposed the hypothesis that Ca2+ participates greatly in the cell communication process (16,17,21). Intracellular ATP is also believed to be associate with cell communication (26). Recently Hax et al (9) have postulated that the intracellular calcium and cyclic AMP produced from ATP by activation of adenyl cyclase are involved in regulation of cell communication.…”

Physicochemical Fundamentals and Thermodynamics of the Membrane Transport of Drugs

“…The mean pore size of cell membranes can be influenced by chemical agents [238]; bivalent cations diminish the membrane permeability. According to KAVANAU [142] these ions link lipid molecules, thereby decreasing the pore diameter; the influence of divalent cations on the structure of protein plugs is more direct due to the ion exchange character of these molecules [286].…”

“…Carrier poisons like SH reagents such as organic Hg compounds anddinitrofluorobenzene as well as guanethidine ~md anaesthetics can also inhibit facilitated diffusion [20,29,62,175,238,254,313,314].…”

“…III.B.). Moreover, some further criteria of active transport [126,268,[299][300][301][302]304,331] are concerned with its dependence on the intensity of cell metabolism [29,112,121,125,144,228,238,259,284], inhibition of it by a fall in temperature [261], and metabolic poisons [29,209,238], by O 2 , and substrate deficiency. The accumulation of a permeant in the cell interior, as proposed by LING [187], TROSHIN [295], HARRIS and PRANKERD [106], SHAW et aI.…”