[The effect of streptomycin on energy metabolism in inner ear tissues in guinea pigs].

Fifty-four guinea pigs were divided into three groups. Group I was injected with streptomycin sulfate 200 mg/kg body wt.ip. for 8 days; group II was injected with streptomycin sulfate 200 mg/kg body wt. and Chinese angelica 2 ml/kg body wt. ip. for 8 days; group III, serving as control, was injected with corresponding volume of water for injection. Glucose and pyruvate levels were determined chemically, ATP, ADP and AMP were determined by HPLC. The hearing reflex thresholds were measured before injection of drug and sacrifice. The glucose content in inner ear tissues of group I and II was found to be lower than that of the control. The pyruvate content in group I and II was higher than that of the control. The ratio of pyruvate to glucose in the group I and II was significantly higher than that of the control, P < 0.05. ATP level in inner ear tissues in group I (50.3 +/- 39.0 micrograms/mg protein) decreased significantly as compared with the control (167.7 +/- 115.4 micrograms/mg protein), P < 0.05, but not in group II (151.6 +/- 124.3 micrograms/mg protein). The energy change in each group was in the range of 0.80-0.84. The hearing reflex threshold attenuation in group I 8 days after injection of drug was slightly lower than that prior to the injection of the drug. The results suggest that streptomycin might inhibit the uptake and metabolism of glucose and decrease the ATP level in the inner ear tissues, and that the inner ear tissues accelerate the metabolism of amino-acids for compensation.(ABSTRACT TRUNCATED AT 250 WORDS)