Endocrine Abstracts

Introduction: Insulin induced Prolonged QTc interval cause severe ventricular arrhythmias and sudden cardiac death.

The purpose of this study is to reveal the effects of metoprolol,diltiazem and pilocarpine on insulin induced prolonged QTc interval(Bazett)

Material-Method: In this study 24 Sprague-Dawley adult male rats were used.Before application under anesthesia ECG were taken in derivation(D)I and normal QTc interval was determined in normoglycemic rats.

For the induction of hypoglycemia 40 U/kg crystalline insulin were injected to the 24 rats.Rats were divided into 4 groups (n=6). After 2.5 hours insulin injection, For first group saline(S), for second 1 mg/kg metoprolol, for the third group 0.8 mg/kg pilocarpine and fort he forth group 1 mg/kg diltiazem were applicated intraperitoneally.

3 hours after insulin injection, blood sugar was measured from all four groups rats tail with stick. 40 mg/dl defined as the limit of hypoglycemia. The all hypoglycemic rats below this value, under anesthesia,QTc was calculated and interpreted by taking ECG in DI

Results: In the first group hypoglycemic (HG) rats which is taken saline QTc interval (0.143±0.01s)is significantly (P<0.05)prolonged than normoglycemic rats QTc (0.123±0.009s)

In the second group HG rats which is taken metoprolol QTc (0.121±0.004s), in the third group HG rats which is taken pilocarpine QTc (0.116±0.002s), in the forth group HG rats which is taken diltiazem QTc (0.129±0.001s) were founded.

QTc intervals in second,third, forth groups HG rats which is taken metoprolol, pilocarpine and diltiazem QTc intervals were significantly (P<0.05)shorten than HG rats which is taken saline QTc (0.143±0.01s).

Conclusion: Pilocarpine,metoprolol and diltiazem prevented elongation in QTc intervals in HG rats.The prophylactic use of this drugs may be an hope by reducing sudden cardiac death in patients taking insulin.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.