The dose-dependent effect of grayanotoxin on the cardiovascular system

Aim: Mad honey (grayanotoxin, GTX) poisoning is caused by a toxin binding to the sodium channels of a cell membrane. This study investigates the dose-dependent effect of GTX on the cardiovascular system. Materials and methods: Twenty-four male Sprague Dawley rats were divided into 4 equal groups. Group 1 was the control group and was administered only saline. GTX-III was administered in doses of 200, 400, and 800 μg/kg for Groups 2, 3, and 4, respectively. After GTX-III injection, blood pressure and heart rate were recorded using an electrophysiological data acquisition system. Results: After 200 μg/kg GTX-III injection, at 31–60 min, the blood pressure decreased significantly from the 84 ± 8 mmHg value of the control group to 53 ± 4 mmHg (P = 0.023). In the group to which 800 μg/kg GTX-III was administered, the blood pressure decreased to 50 ± 7 mmHg and 54 ± 5 mmHg in the postinjection periods of 31–60 and 61–90 min, respectively. These values were significantly different from the 70 ± 6 and 84 ± 8 mmHg values recorded for the control group. The heart rate in the group injected with 400 μg/kg GTX-III decreased significantly 40 min after injection. In the 800 μg/kg GTX-III group, the heart rate decreased significantly 20 min after injection. Conclusion: According to our findings, the bradycardiac and hypotensive picture seen in patients applying to the clinic with mad honey poisoning also emerges clearly in experimental animals at the high dose of 800 μg/kg GTX-III.