Abstract
The osmosis of the muscle cell membrane (sartorius muscle of Rana catesibiana) was studied by measuring the weight of muscle which was soaked in various solution.
Even in isotonic solution of CaCl2 or sucrose, the muscle cell lost its water remarkably. But in the isotonic KCl solution, the cell absorbed the water from the environment.
On the contrary, the water content of the cell was kept constant in isotonic NaCI solution.
The osmotic pressure of Ringer's solution, of isotonic CaCl2 and of NaCl solution were raised by adding sucrose. The water content of muscle was decreased exponentially in such hypertonic solutions.
Procaine promoted the muscle to lose water in hypertonic solution, but contrarily eserine inhibited it.
From above mentioned facts, it was concluded that the most important factors in the mechanism of efflux or influx of the water molecule through muscle cell membrane were following two ; (1) the difference of osmotic pressures between the environmental solution and muscle cells, (2) shift of K+ and other inorganic rations with bound water through the membrane.
