Cardiotoxicity study of the aqueous extract of corn silk in rats

Abstract

In the ear of corn there are silky strands which run its length and these strands are known as corn silks. Folk remedies show that the corn silks have been used as an oral antidiabetic agent in China for many years and as herbal tea in other world nations for the amelioration of urinary tract infection. The extract is being assessed for safety in this study using histopathological changes, as well as an electrocardiogram (ECG). Graded doses (200, 400 and 800 mg/kg) of aqueous CS extract were administered to rats for seven days. The fourth group which served as control received 3 ml/kg dose of distilled water. On the eighth day, ECG was evaluated in ketamine/xylazine-induced anaesthesia in rats to determine changes in the heart rate, P-wave duration, P-R interval, R-amplitude, QRS duration, QT interval and QTc. Hearts from the experimental animals were collected for histopathological changes. The results showed that there was a significant change in the heart rate (groups B and C), P-wave duration (group D), QT interval (groups B, C and D) and QTc (groups B, C and D) when compared to the control group. Histology also indicated that sections of the heart showed fatty infiltration of infl amed heart and areas of moderate inflammation of the atrium and ventricle. It could therefore be concluded from this study that though folklore indicated that corn silk (CS) is of high medicinal value, one must be careful in using this product as medicinal agent especially in patients with compromised heart conditions.