Effects of a low concentration of ethanol on the potential difference of mucous-secreting glands of the toad Pleurodema thaul.
The effect of noradrenaline on the bioelectric activity of the mucous glands of 9 toads was studied by means of intraglandular recording. Noradrenaline induced a transient increase in glandular secretion and a simultaneous two-phase increase in the potential difference of the glands. Perfusion with 0.043 mM ethanol-Ringer's reversibly reduced this response. Ouabain, in concentrations which block Na+K+-activated ATPase, markedly reduced the slow phase of the response of the 'isolated skin to noradrenaline. The results suggest that ethanol acts in two ways: first by increasing the electrical resistance of the skin and secondly by partially inhibiting the active transport of sodium due to a decrease in permeability of the apical membrane of the transporting cells.
D000818:Animals; D001001:Anura; D001693:Biological Transport, Active / Q000187:drug effects; D004594:Electrophysiology; D000431:Ethanol / Q000494:pharmacology*; D005088:Exocrine Glands / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D009093:Mucus / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D012964:Sodium / Q000378:metabolism
D000431:Ethanol; D010042:Ouabain; D012964:Sodium; D009638:Norepinephrine