| Abstract: | The effect of theophylline, an inhibitor of cyclic nucleotide phosphodiesterase, on electrical activity of bursting neuron RPa1 ofHelix pomatia was investigated. In a concentration of 1 mM theophylline, when added to the external solution, increases the frequency and number of action potentials in the burst and also the duration of the inter-burst interval and the amplitude of membrane potential waves. In concentrations of 2.5 and 5.0 mM theophylline leads to reversible inhibition of bursting activity. During rinsing this activity rises to a higher level and then returns to the original value. The action of theophylline develops and disappears (as a result of rinsing) in the course of 1–5 min, depending on concentration of the inhibitor. It is suggested that electrical activity of the molluscan bursting neuron is controlled through the cyclic nucleotide system.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 13, No. 1, pp. 75–79, January–February, 1981. |
