Effects of toxic honey containing grayanotoxin-I on fatigue of frog gastrocnemius muscle

ABSTRACT

This study aims at investigating the effects of honey containing grayanotoxin-I [GTX-I] on fatigue produced by electrical stimulation in frog gastrocnemius muscle. We used two groups of gastrocnemius muscles isolated from curarized frogs. The isolated muscle preparations in the first group were perfused with Clark-frog-Ringer's and ordinary honey [from Mediterranean Sea region of Turkey] solutions respectively. The second group of preparations were first perfused with Clark-frog-Ringer's then with GTX-I containing toxic honey [from Black Sea Region of Turkey] solutions. Perfusion was made externally, and bipolar Ag/AgCI wire electrodes were used for stimulation. Muscles were stimulated directly with supramaximal square-wave pulses of 0.5 ms at a rate of 30 stimuli/min, and isometric contractions were recorded. As indicators of muscle fatigue we have used the increases both in contraction and relaxation times and the decrease in contractile force. It has been shown that the toxic honey containing GTX-I delayed the muscle fatigue by preventing the decrease in contractile force