Abstract
Using a modified Hot-plate Method by Woolfe and Macdonald, a detailed investigation was made as to the reactions exerted in mice to the painful heat stimulus, which were divided then into two groups, i.e. the tremor as a first reaction ; bending or lifting up the hind limbs, etc. and the second reaction ; licking the sole of back paw or jumping, etc.. From the results of experiments in normal as well as in spinal mice it has been proved that the first reaction is of spinal nature and it disappears ever after spinal depressant drugs, while the second reaction is derived from supraspinal origin. The more reliable estimation will be, therefore, obtainable by making the second reaction as the algesimetric standard of drug effects. Further, other essential problems as to the algesimetric methods are also discussed.
