The Sensex at the Bombay Stock Exchange opened 76 points higher in opening trade today on emergence of buying in fundamentally strong shares at lower levels. It later gained further points and was trading at 18316 up by 142 points a short while ago. In a similar fashion, the wide-based National Stock Exchange Nifty index rose by 22 points or 0.41 per cent in the opening trade and is trading at 5492 which is up by 45 points.