| Popis: |
1. 1. The effects of the omission of Na + , K + and Ca 2+ as well as the excess of Na + , Ca 2+ and Mg 2+ were studied on the resting and action potentials of the hearts of Locusta migratoria migratorioides, Mantis religiosa and Phaneroptera nana . The action potential generation was stopped in Na + and Ca 2+ free solution and in the high concentrations of these ions. 2. 2. The rising phase of the action potentials proved to be Na + and Ca 2+ dependent as tetrodotoxin (1 × 10 −4 M) and Mn ions (4 mM) alike damaged the potential generation. The hearts of the insect species investigated did not generate Na + -independent action potentials. 3. 3. The Mg-ions did not play a role as current carriers in the generation of action potentials in the heart of the species studied. |
