Abstract
The pilocarpine iontophoresis test (P-test) is used as a predictor of the capacity to produce sweat. Therefore, we studied the reproducibility of this test in 12 normal subjects on 10 consecutive days. Furthermore, we determined whether the P-test reflects whole-body and regional sweat secretion during exercise in the heat. Finally, we determined whether the P-test stimulates the eccrine sweat glands to maximal sweat secretion. Six growth hormone-deficient (GHD) patients who are known to have decreased sweating, and 11 healthy control subjects were studied. To induce maximal sweat secretion, the patients exercised on a bicycle ergometer at a workload corresponding to 40% of their maximal aerobic power (VO2max). The 11 healthy subjects exercised at a workload of 150 W. All subjects exercised for 60 min in ambient air at 35 degrees C, with 50% relative humidity. The P-test showed a mean day-to-day variation of 20.8% between individual subjects. There was a significant positive correlation between the P-test and regional sweat secretion (r2 = 0.74). The correlation coefficient (r2) was 0.50 for the correlation between the P-test and whole-body sweat secretion, and 0.52 for the correlation between regional sweat secretion and whole-body sweat secretion. We conclude that the pilocarpine iontophoresis test reflects heat- and exercise-induced sweating capacity. However, this test does not induce maximal sweating, and it cannot be used as a single reliable predictor of whole-body sweating, due to considerable day-to-day variation.
| Original language | English |
|---|---|
| Journal | Clinical physiology (Oxford, England) |
| Volume | 15 |
| Issue number | 4 |
| Pages (from-to) | 409-14 |
| Number of pages | 6 |
| Publication status | Published - 1995 |