抄録
In an attempt to clarify the aspect of the acetylcholine (Ach) metabolism occurring within the cochlea of the guinea-pig, determinations of aeetylcholin-esterase (ChE) activity within it have been made, and the alteration of ChE under pathological conditions was studied. The animals were exposed to sounds or were given D.H.S.M. and D.F.P. systemically. The ChE activity was quantitatively determined with use of Cartesian diver respirometer. By the freezing and melting procedures, the ChE activity was expressed in terms of “functional and reserve ChE.”
The following results were obtained:
1) In normal specimens, ChE activity per mm in the lower coil was greater than in the upper coil, but by the freezing and melting procedure, its activity increased in both coils within a similar range.
2) In the tissues of the sound-exposed animals, functional ChE diminished in the lower coil, while reserve ChE in the upper coil diminished.
3) In the tissues of the D.F.P.-injected animals, both functional and reserve ChE slightly diminished in the both coils.
4) In the tissues of the D.H.S.M.-injected animals, considerable individual differences of ChE were characteristic, though both types of ChE decreased on the average.
5) ChE in the cochlea showed a tendency to change its activity characteristic-ally under each above-mentioned pathological condition.
