[Objective] The aim was to probe into developing changes of spontaneous electrical activities of primordial hippocampus in Bufo bufo gargarizans in postembryonic phase. [Method] Microelectrode technique was used to record extracellularly spontaneous electrical activities of neurons in primordial hippocampus of B.bufo gargarizans in postembryonic phase. [Result] Single, consecutive single, burst, consecutive burst and anomalous spontaneous firing were recorded in primordial hippocampus, in which four kinds of spontaneous firings were recorded in forepart of postembryonic development except the anomalous spontaneous firing, and the burst spontaneous firing and consecutive burst spontaneous firing were predominant. The five kinds of spontaneous firings mentioned were recorded in anaphase of postembryonic development and the single and burst spontaneous firing were predominant.Following with the development of primordial hippocampus, the amplitudes of action potential of single firing and consecutive firing enhanced gradually, and it reaches the maximum in the metamorphosis phase; the differences of the frequencies of consecutive single firing and consecutive burst firing were not significant. [Conclusion] Following with the development of primordial hippocampus, the neuronal electrical activities showed diversification, the developmental degree of the primordial hippocampus in the metamorphosis phase was close to the subadult and adult.
Objective In order to probe into the morphological and histological characteristics of the telencephalon of Onychodactylusfischeri, and to enrich the comparable neurobiology. Method HE-staining method was used to describe the characters of the telencephalon of Onychodactylus fischeri. Results The olfactory bulb of Onychodactylus fischeri locates in the rastral and lateral to the cerebral hemisphere, and six distinct layers can be identified from the lateral to the medial, quite similar to Batrachuperus tibetanus and Hynobius leechii. In the cerebrum, the primordial hippocampus developed better than the primordial piriform. The former belongs to archipallium and the latter is paleopallium. Ventral to the primordial hippocampus there is a septal area which cannot be divided into medial and lateral parts. In the ventrical wall, there is neither medial limiting sulcus nor lateral limiting sulcus to saperate the primordial hippocampus and the septal area, or the primordial piriform and the corpus striatum. The corpus striatum of Onychodactylusfischeri is paleostriatum. There is choroids plexus anterior in the lateral ventricle. The cell group that located at two sides of the third ventricle is the amygdale. Besides, the shape and size of neurons within the telencephalon are poorly differentiated. Conclusion Onychodactylusfischeri is a relatively primitive type in the amphibian. The present data will help us to further understand the nerve system of tailed amphibian.
Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microelectrode technique was used to record extracellular spontaneous electrical activities of olfactory bulb in B. gar-garizans. [Result] Along with the development of olfactory bulb, the discharge types increased gradual y. Single spontaneous firing enhanced gradual y and it reached the maximum in the metamorphosis phase. The intensity of consecutive single sponta-neous firing changed slightly at the middle of post-embryonic development, but it was stil higher than in the early phase and the adult phase. Consecutive burst spontaneous firing frequency went down over time. [Conclusion] Along with the de-velopment of olfactory bulb, the neuronal excitability increases step by step and the neuronal electrical activities diversify gradualy.
This study aimed to probe into occurrence and development of spontaneous firings in the telencephalon neurons of Hynobius leechi . [Method] Mi-croelectrode technique was used to record extracellular spontaneous electrical activi-ties of the telencephalon neurons of H. leechi in occurrence and development. [Re-sult] There were three discharge types in the occurrence of telencephalon in H. leechi , with single spontaneous firing and consecutive single spontaneous firing being main-ly apparent. And among the five types in the development of telencephalon, the main discharge type was single spontaneous firing. Along with the occurrence and development of telencephalon, the extracellular discharge intensity enhanced gradual-ly, the discharge duration increased, and the spontaneous firing frequency accelerat-ed, al of which reached the maximum in the adult phase. Fol owing the process of occurrence and development, other discharge types appeared successively. [Conclu-sion] Along with the occurrence and development of the telencephalon in H. leechi , the neuronal excitability increases step by step and the neuronal electrical activities diversify gradual y.
