Radiation response of murine eccrine sweat glands

Following irradiation of the left-hind feet of mice, we measured the ability of the eccrine glands to secrete sweat following stimulation by pilocarpine. Silicone elastomer impression moulds of the foot pads gave repeatable, detailed localization of sweat ducts by retaining the impression of each emerging sweat droplet. Loss of gland function occurred rapidly following irradiation (within 2 weeks) and the rate of loss was dose-dependent, being over three times greater following a dose of 13.0 Gy than after 6.8 Gy. There was a dose-dependent nadir of function at around 8 weeks, followed by a gradual recovery that was complete by about 30 weeks after irradiation, leaving a dose-dependent residual functional deficit. Eccrine sweat glands are very radiosensitive organs compared with the epidermis. A single dose of 13 Gy resulted in complete loss of eccrine gland function at 8 weeks whilst about 23 Gy would be required to elicit transient moist desquamation, in oxygen-breathing mice. Substantial sparing was seen when two doses were split by intervals of up to 24 h.