Chemistry of Palmar Sweat

The Rationale for Treating the Change in Galvanic Skin Response as a Change in Conductance

“…Clearly GSRs are recorded at high resistance levels in the absence of recorded sweating. It seems also clear that during active sweating the lower levels of resistance reached must be attributable to the excellent conduction pathways provided by filling of the sweat tubules with highly conductive sweat having a high NaCl content (11) and also presumably to the active depolarization of the deep-lying sweat gland membranes. Thus, the wide range of electrical changes recorded as GSR are probably in reality a consequence of two overlapping phenomena, one at low levels of excitation involving high apparent resistances and large apparent resistance changes in the relatively non-conducting surface layers of the skin, and the other at high level activity with low apparent resistances and small resistance changes involving both depolarization of the deep-lying sweat gland membranes and saline sweat flow in the tubules connecting surface electrodes with the interior.…”

The Sweat Glands

“…The high values reported by Lobitz and his colleagues (Lobitz & Osterberg, 1947;Lobitz & Mason, 1948) are in profound contrast to those referred to above; the figures in fact far exceed that for plasma. Moreover, the values were lower when sweating was intermittent and slower than when it was profuse-the reverse of what has been generally found for thermogenic sweat.…”

“…The fact that quite small quantities can be collected from the human palm suggests that successful collections on the monkey palm and the cat's paw ought to be possible. Lobitz & Osterberg (1945) have used a very delicate and rather difficult technique of picking up by micropipette, under the dissecting microscope, sweat appearing on the pores on the finger. Our colleague, Mr K. Collins, has found it much easier to use, on the palm, a modified form of the chamber collecting method described by Schwartz, Thaysen & Dole (1953).…”

“…The pH of palmar sweat has much the same range (Lobitz & Osterberg, 1945 ;Collins, unpublished). Ammonia is also present in the palmar sweat (Lobitz & Mason, 1948).…”

Heat Stress and Nutrition

“…T h e sweat glands of normal individuals are able to conserve most body nutrients very efficiently. Thus the losses of all the vitamins are small (Mitchell & Edman, 1951) and only traces of glucose appear (Lobitz & Osterberg, 1947). T h e losses of nitrogenous compounds, other than urea, are also almost certainly small, but have proved difficult to measure because of the contamination of sweat with products of dermal origin (Rothman, I 954).…”