title: [Changes in the ionic mechanisms of the electro-excitability of the somatic membrane of rat sensory neurons during ontogenesis. Relation between calcium channels and intracellular metabolism].
abstract: A change in the relationship between high-threshold calcium channels and intracellular metabolism of cyclic nucleotides during postnatal development was found in experiments on rat dorsal root ganglion neurons. In the first age group (5-9 postnatal days) intracellular administration of cAMP-ATP-Mg2+ complex has resulted in restoration of the maximal amplitude of high threshold calcium current for 70% of neurons, whereas in the second (45 days) and third (90 days) age groups this effect was observed only in 26% and 10% of neurons, respectively. Kinetic and voltage-dependent characteristics of high-threshold calcium current in these three age groups were identical. The effect of introduction of cAMP-ATP-Mg2+ complex was different for neurons with different combination of inward currents. Neurons which possessed only two types of inward currents--"fast" sodium and high-threshold calcium ones, show no effect. Conventional effect of the intracellular cAMP injection occurred always in neurons which had exhibited a "slow" (TTX-resistant) sodium inward current together with the two main inward currents.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000375:Aging / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism*; D005727:Ganglia, Spinal / Q000254:growth & development / Q000502:physiology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000502:physiology*; D008274:Magnesium / Q000378:metabolism*; D008564:Membrane Potentials; D009475:Neurons, Afferent / Q000502:physiology; D051381:Rats
chemical_list: D007473:Ion Channels; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D008274:Magnesium; D002118:Calcium
vernacular_title: Izmenenie ionnykh mekhanizmov élektrovozbudimosti somaticheskoĭ membrany sensornykh neĭronov krys v ontogeneze. Sviaz' kal'tsievykh kanalov s vnutrikletochnym metabolizmom.