First identification of a trail pheromone of an army ant (Aenictus species)

Totally blind army ants carry out massive and highly organised foraging raids, apparently guided by chemical stimuli. Until now, this phenomenon has not been closely analysed. The existence of a trail pheromone in a postpygidial gland of anAenictus species has been demonstrated and the substances identified as methyl anthranilate and methyl nicotinate The pheromone consists of two parts: a primer effect, caused by methyl nicotinate, which prepares workers to follow trails, but is not itself followed, and a releaser effect, due to methyl anthranilate, which causes trail-following only in conjunction with the primer substance.     

Effects of dimethylsulfoxide (DMSO) and potassium chloride on the resting potential of the isolated frog nerve

Zusammenfassung Da DMSO da Ruhepotential depolarisiert, verglichen wir seine Wirkung mit der von Kaliumchlorid. Infolge verschieden schneller Depolarisationen und einer jahreszeitlich abhängigen Ruhepotentialänderung durch Kaliumchlorid schliessen wir auf unterschiedliche Wirkungsmechanismen beider Substanzen. DMSO hat ausser einer Kurzzeitwirkung einen länger persistierenden reversiblen Effekt auf die Nervenmembran, der durch nachfolgende kurzwirksame Kaliumchloriddepolarisationen nachgewiesen werden kann.

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Acknowledgement: The authors express their appreciation to MissMonika Höcker for her skillful technical assistance.