Effects of Ca- and K-Ions and Ultra-Violet rays upon involuntary muscles

Abstract

The antagonistic action of calcium and potassium ions in nutritive solutions has been previously studied by many. According to S. Ringer (1) calcium is necessary in the case of the frog’s heart to abolish the toxic action of a physiologically isotonic solution of sodium chloride and maintain the tone of this organ, and potassium controls the action of calcium. S. G. Zondek (2), studying the relationship between the vegetative nervous system and these ions, concluded that the action of sodium and potassium ions is similar to that of the vagus nerve, while the action of calcium corresponds to that of the sympathetic. The relationship between Ca- and K-ions and ultra-violet rays is of interest. According to Rothman (3) the calcium content of the normal blood is increased when erythema and pigmentation of the human skin results from irradiation with ultra-violet rays. Pincussen (4), investigating this matter, showed that the calcium content is not greatly affected, while that of potassium is decreased; in other words, the ratio of K/Ca decreases after the light bath. It is of interest that adrenalin (a stimulant of sympathetic nerve endings) has the contrary action when injected into animals or human beings; it causes in the blood a decrease of calcium (5) and increase of potassium (6).

Characterization of Ultraviolet Light‐induced Relaxation of the Isolated Duodenum of the Rat

“…Kolm & Pick (1920) found lightinduced stimulation of sensitized intestinal smooth muscles which was cholinergic in nature. Similar photostimulation responses of smooth muscles have been observed by other workers (Adler, 1919;Harris, 1925;Azuma & Hill, 1926;Azuma, 1927;Supniewski, 1927;Blum, 1941). Light-induced relaxation responses of smooth muscle preparations have also been reported.…”