The relation between the effects of ketamine on mechanogram and Ca+2 ATPase on nerve-muscle preparation [KETAMIN'IN SINIR-KAS PREPARATLARINDA MEKANOGRAM UZERINE ETKILERININ CA+2 ATP'AZ ILE ILISKISI]
The aim of this study was to determine the effect of ketamine on muscle contraction force and Ca+2 ATPase enzyme activity in the rat phrenic nerve-hemidiaphragm muscle preparation. This study was approved by ethical committee. Wistar strain Albino rats, weighted 200-230 g, were used in this study (n=24). Animals were killed with cervical dislocation and phrenic nerve-hemidiaphragm muscle was prepared. Muscle was placed between two platen electrodes and connected to a isometric force tranceducer which was stimulated hanged in the tissue bath which contains krebs solution at 37°C. Following the 30 minutes of stabilization, muscle was stimulated with direct and indirect electrical pulses supramaximally. The peak tension was recorded with an oscillograph. Initial normal muscle contraction force was recorded before adding 21, 31.6, 42, 52.6, 42, 63, 73.8 µM of ketamine into the solution. After this period, at each concentration enzyme activity was measured in the 10 % hemidiaphragm muscle homogenate, which was prepared in 0.32 % sucrose with 1 mM Mg++ for each ketamine concentration. While, the muscle contraction force was increased at 21, 31.6, 42 µM ketamine concentrations, however concentrations of ketamine (52.6, 63, 73.8 µM) was reduced the peak tension. A proportional dose dependent Ca+2 ATPase enzyme activity reduction with higher ketamine concentrations was determined. According to our results, ketamine decreased the muscle contraction and Ca+2 ATPase enzyme activity
