Effect of Procaine, Calcium, Magnesium and Potassium on the Acetylcholine Release from the Sweat Nerve Endings in Human Skin
1968 Volume 95 Issue 3 Pages 297-311
Details
1968 Volume 95 Issue 3 Pages 297-311
The effects of procaine, Ca, Mg and K on the release of transmitter from the cholinergic sweat nerve endings in the forearm skin were studied. Sweating was visualized by the iodine-starch method of Wada and Takagaki.
At a concentration of 10-7, intradermal injections of eserine did not produce a local sweating in a cool environment, but they became effective in eliciting sweat response on the injection wheals by entering a warm or hot environment. Local sweat responses to eserine in 10-6 and 10-5 were also intensified on exposure to heat.
Procaine in 10-4 inhibited the sweat responses to eserine very probably by affecting the acetylcholine release from the sweat nerve endings. It was found that Ca ions contained in Krebs solution are important in the process of the acetylcholine release and excessive Ca facilitates this release. In contrast, Mg and K ions present in Krebs solution were without any effect. But, when Mg was in excess relative to Ca, it was observed that Mg antagonized the effect of Ca. The antagonism between Mg and Ca was demonstrated also in the case of spontaneous thermoregulatory sweating. The effect of Ca on the acetylcholine release seems to be antagonized by Mg in a ratio of approximately 1:2 in molality.
