THE CONTROL OF POTASSIUM (86Rb+) EFFLUX IN THE ISOLATED HUMAN SWEAT GLAND

¹ The Institute of Physiology, University of Glasgow, Glasgow G12 8QQ
² The Moredun Research Institute, Edinburgh EH17 6JH

Sweat glands, isolated from strips of human skin and pre-loaded with ⁸⁶Rb⁺, a marker of potassium transport, were superfused with physiological saline and rate constants for ⁸⁶Rb⁺ efflux calculated. The rate of efflux during superfusion with Ca²⁺-free saline was lower than that measured in the presence of calcium (2·56 mM). Acetylcholine increased the rate of ⁸⁶Rb⁺ efflux and this response could be resolved into two components: an initial transient phase which was Ca²⁺-independent and a slowly declining Ca²⁺-dependent phase. Adrenaline only caused a Ca²⁺-dependent increase in efflux. It is suggested that the potassium permeability of the secretory cells increases during activity.