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L M Chuppina

Publications and source records attributed to L M Chuppina.

14 recordsLinked to original sources
PubMed1983

[Maturation of neuronal elements of the cerebellum in tissue culture].

The morphological and electrophysiological indices of the process of nervous cells differentiation were observed in the organotypical cerebellar culture of the newborn mice. The cerebellar cells reached the morphological maturity in the 18-21 day culture. The membrane potential augmentation began in the 6-7 day culture and reached the magnitude typical for the definitive stage of neuron (65-75 mV), in the 9-10 day culture. Spontaneous APs were recorded only in the 10-12 day culture, their characteristics being sharply different from those of the mature neuron. The difference reduced by the 16-18th day. The final maturity of cerebellar neurons, however as indicated by the AP, occurred still later and correlated with formation of the specific sensitivity of these cells to acetylcholine.

Acetylcholine↗
PubMed1981

[Electrophysiologic and neurochemical characteristics of cultured cortical neuroblasts from newborn rats].

The neuroblasts of the newborn rat cortex continued to be differentiated in cultured tissue judging by growth of the MP, the possibility of its recording during a longer time (10--15 min) and the transmitter sensitivity. At a certain stage of the differentiation the heterogeneity of the morphologically uniform neuroblasts is manifested by the obvious difference between MP values and patterns, by the presence of neuroblasts with stable and fluctuating MPs, and by the variety of responses to application of ACh and GABA. The neuroblasts at a rather early stage of their development revealed absence of AP, lesser MPs, reduced sensitivity to ions, no transmitter sensitivity.

Acetylcholine↗
PubMed1977

[Effect of single stimuli to the posterior hypothalmus on the visual evoked potentials of an anesthetized rabbit].

Single stimuli applied to the posterior hypothalamus evoke in the visual cortex of anesthetized rabbits a hypothalamic--cortical response with short latency, marked premarily--positive and negative components, and secondary positive wave of a large amplitude. It seems that projections from the posterior hypothalamus to the cortex are multiple, pass through different subcortical structures and terminate with different synaptic organizations. Single stimuli applied to the posterior hypothalamic nuclei with intervals from 700 to 100 msec facilitate a visual evoked potential due to enhancement of the negative component. Apart from the facilitation of the visual response, the area where the potential can be recorded is enlarged by single stimuli applied to the posterior hypothalamic nuclei.

Animals↗
PubMed1976

[Chemical heterogenicity of the synaptic organization of different regions of the rabbit cerebral cortex].

In anesthetized rabbits, visual EP was recorded in the temporal cortex, and EP elisited by stimulation of the n. ischiadicus--in the somatosensory cortex. Application of 1% GABA, glycine, and nembutal solutions to the site of EP recordings increased the visual EP and diminished the somatosensory EP. The data obtained seem to corroborate the chemical heterogeneity of synaptic organizations of the visual and somatosensory cortex in the rabbit brain.

Aminobutyrates↗
PubMedDate not supplied

Effect of single stimulation of the posterior hypothalamus on visual evoked potentials in anesthetized rabbits.

During single stimulation of the posterior hypothalamic nuclei an evoked hypothalamo-cortical response with a short latent period, well-marked primary positive and negative components, and a secondary positive wave of high amplitude was recorded in the visual cortex of rabbits anesthetized with pentobarbital. It is postulated that pathways from the posterior hypothalamus to the cortex are numerous, pass through various subcortical structures, and terminate in different synaptic organizations. Single stimulation of the posterior hypothalamic nuclei at intervals of between 700 and 100 msec facilitate the visual evoked potential on account of an increase in its negative component. Besides facilitation of the visual response, during single stimulation of the posterior hypothalamic nuclei the zone of recording of the visual evoked potential is widened.

Animals↗
PubMedDate not supplied

Maturation of cerebellar neuronal elements in a tissue culture.

The process of differentiation of neurons was traced on an organotypic cerebellar culture of newborn mice. Cerebellar cells reach morphological maturity by the 18-21st day of culturing. An increase of the membrane potential begins on the 6-7th day of culturing. It reaches values characteristic for the definitive stage of the neuron (65-75 mV) by the 9-10th day of culturing. Spontaneous action potentials begin to be recorded on the 10-12th day of culturing. At this time they markedly differ in their characteristics from the action potential of the mature neuron. The differences become less noticeable by the 16-18th day of culturing. However, final maturation of the action potential occurs at later times. The formation of specific sensitivity of cerebellar neurons to acetylcholine correlates with the time of formation of the action potential.

Acetylcholine↗
PubMedDate not supplied

[Change in the chemical sensitivity of the visual cortical synapses in rabbit ontogeny].

In experiments on newborn rabbits under nembutal (pentobarbital) anaesthesia, studies have been made on changes of visual evoked potential in the visual cortex during application of 1% solutions of GABA and nembutal. At the age of 7--9 days, these drugs decreased the evoked response, which may be associated with their hyperpolarizing effect on cortical synapses. Between the 11th and the 13th days, no effect of GABA and nembutal upon the evoked potential was noted. Definitive reaction to application of these pharmacological drugs typical for adult animals is formed not earlier than to the 15th--17th day. Beginning from this time, application of GABA and nembutal significantly increases visual evoked potential. The postnatal evolution of chemical sensitivity of postsynaptic membrane of neurons of the visual cortex in rabbits is discussed.

Animals↗