The role of glandular activity in the electrical response of amphibian skin to noradrenaline.

1. The electrical response of isolated amphibian skins to the presence of 4 x 10(-5)M noradrenaline in the inner medium has been studied.2. The response to noradrenaline consists of a transient secretion from the skin glands, a transient increase in the short-circuit current, a transient decrease in the skin resistance and a partial depolarization of the skin potential (inside surface becoming less positive) followed by a hyperpolarization.3. The origin of the initial depolarizing phase of the response to noradrenaline has been studied.4. It is considered that the initial depolarization results partially from an increase in the chloride permeability of the outer membranes of the epithelial cells and predominantly from the emergence of an additional transient shunt pathway in the skin.5. It is proposed that during secretory activity the skin glands constitute the transient shunt pathway responsible for the initial depolarizing phase of the response to noradrenaline.