6533b834fe1ef96bd129cc0d

RESEARCH PRODUCT

Metabolic aspects of the rhythmogenesis inAplysia pacemaker neurons

subject

description

Completely isolatedAplysia pacemaker neurons were used to investigate mechanisms of endogenous electrical rhythmicity. This preparation allows the study of pure pacemaker activity free from synaptic, ephaptic and/or humoral influences from the surrounding cells. The effect of some substances quite different in their mode of biochemical action were tested: sodium iodoacetate, phloridzin, dinitrophenol, heavy water, and ouabain. Each of these substances suppressed the spontaneous spike activity without any marked depolarizing or hyperpolarizing effect. Spontaneous spike activity of the neurons silenced after addition of one of these substances reappeared after addition of glucose. The restoring effect of glucose failed in beating pacemaker neurons silenced by ouabain, but is present in ouabain silenced pacemaker cells of the oscillatory type. It is suggested that two basic biochemical processes: glycolysis and ATP hydrolysis are involved in the rhythmogenesis. The results offer some hints that the spike rhythms of pacemaker neurons depend on a certain balance between glycolytic processes and ATP hydrolysis.