The changes of skeletal muscle cellular membrane potential(SMCMP)were determined in vivo with the technique of“semi-floating”glass mic-roelectrode in different phases of irreversible hemorrhagic shock in rab-bits.The distribution of extra-and intracellular electrolytes and waterwas studied at the same time.It was found that SMCMP decreased significantly as soon as hypoten-sion occurred,the potential continued to decrease as shock becameprogressively worse,and the leakage of intracellular potassium and reten-tion of intracellular sodium and water occurred 3 hours after the onsetof shock.These facts indicate that the functions of cellular membranebegin to deteriorate in the early stage of shock,the deterioration of thefunctions of the cell proper supervenes as shock progresses,and eventual-ly the cell fails to regulate their volume. The changes of skeletal muscle cellular membrane potential (SMCMP) were determined in vivo with the technique of “semi-floating” glass mic-roelectrode in different phases of irreversible hemorrhagic shock in rab-bits. The distribution of extra-and intracellular electrolytes and waterwas studied at the same time. It was found that SMCMP decreased significantly soon as hypoten-sion occurred, the potential continued to decrease as shock became more progressive and the leakage of intracellular potassium and reten tion of intracellular sodium and water occurred 3 hours after the onset of shock. thesefact facts that that functions of cellular membranebegin to deteriorate in the early stage of shock, the deterioration of thefunctions of the cell proper supervenes as shock progresses, and eventual-ly the cell fails to regulate their volume.