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B Berdel

Publications and source records attributed to B Berdel.

25 records · Page 2Linked to original sources
PubMed1996

Acetylcholinesterase activity as a marker of maturation of the basolateral complex of the amygdaloid body in the rat.

Development and maturation of the basolateral complex of the amygdaloid body were studied in fetal and postnatal rat brains. In cresyl violet-stained sections the basolateral complex was distinguishable at the 17th prenatal day. On about the 14th postnatal day, it showed all the features of the adult structure. The acetylcholinesterase activity appeared in neuropil of the basolateral complex on the seventh postnatal day; it increased slowly up to the 60th day. After that age, the acetylcholinesterase activity was stable in all parts of the basolateral complex and corresponded to its cytoarchitectonic differentiation. Our results suggest that the process of maturation of the amygdaloid basolateral complex, being related to the ingrowing of the cholinergic fibers from the basal forebrain, lasts at least up to the end of the second month of postnatal life.

Acetylcholinesterase↗
PubMed1995

Influence of fixation and histological procedure on the morphometric parameters of neuronal cells.

The influence of fixation and histological procedure on morphometric parameters of human and rat brains were analyzed. We found negative correlation of brain weight with the fixation time both in human and rat material. Human brains fixed for shorter period of time than one year showed large differences in weight. The group of brains fixed for longer than one year was characterized by much smaller dispersion. Moreover, we found that during histological preparation the shrinkage of brain tissue of older human subjects is statistically significantly smaller than younger ones (below 65 years). In order to correct these artifacts easily we propose three simple formulas.

Adult↗
PubMed1994

Insular claustrum of the dog--a morphometric investigation of cellular structure.

Investigation of the dog's insular claustrum was performed using morphometric methods. The brains of 14 dogs (7-14 year-old) were studied. The size, shape and density of neurons are different in various parts of the insular claustrum. The posterior part, related to the visual system, is heterogenous and possesses medium-sized and small densely packed neurons, the average cross-sectional area of cell body being 175.8 +/- 45.5 micron2. The similar average cross-sectional area of cell body (174.1 +/- 55.3 micron2) was found in the central part of the insular claustrum. However, neuronal architecture is here less heterogenous and neurons are less densely arranged. The anterior part, connected mainly with the frontal and motor cortex, is more homogenous and contains loosely arranged neurons of a rather large size (average size--198.7 +/- 53.46 micron2).

Animals↗
PubMed1994

The insular claustrum in the methylazoxymethanol acetate (MAM) treated rats shows two different populations of neurons.

Methylazoxymethanol acetate (MAM) is a substance that inhibits migration of neurons in the embryonic brain. After intraperitoneal injection of two different doses of MAM to pregnant rats, microcephaly with or without complete development of the cerebral cortex was observed in every litter. High MAM doses (30 mg/kg) resulted in the lack of superficial layers (II-IV) of the cerebral cortex when the deep layers (V, VI) were seen. The claustrum was present but composed of loosely packed, medium-size, triangular or fusiform neurons with anarchic oriented long axes. After administration of low MAM doses (14 mg/kg) two different parts (medial and lateral) of the insular claustrum were observed. Our results suggest that neurons of the insular claustrum create two different subpopulations of cells, which were similar to that observed in primitive insectivore (e.g., hedgehog), but fuse in development.

Animals↗
PubMed1994

Variability of the parahippocampal surface of the transverse fissure in the human brain.

The parahippocampal (ventral) surface of the lateral part of the transverse fissure (LTF), formed by the parahippocampal gyrus, was examined in 53 human brain hemispheres without pathological changes. Cytoarchitectonics of this region was studied on the frontal histological sections stained either with cresyl violet or with Weil method. Four types of the shape of the parahippocampal surface of LTF were distinguished. In type 1 the surface is either flat or elevated in its medial part (medial eminence; 34.0%). In type 2 the surface is elevated in its lateral part (lateral eminence, 24.5%). In type 3 there are two eminences--the lateral and the medial; both of similar height (20.8%). In type 4 the lateral eminence is distinctly higher than the medial one (20.7%). The eminences contain cytoarchitectonically different structures. The lateral eminence is formed mainly by the subiculum and CA1 area, the medial by the presubicular region. The shape of the parahippocampal surface of LTF may be of importance in assessment of the Alzheimer's disease pathology.

Adult↗
PubMedDate not supplied

Tactile experience induces c-fos expression in rat barrel cortex.

Understanding gene expression that is responsive to sensory stimulation is central to elucidate molecular mechanisms underlying neuronal plasticity. In this study we demonstrate two new methods of stimulating whiskers that provide major sensory input to rat neocortex. In the first paradigm, animals were placed on the top of a cylinder and their vibrissae were brushed by hand. In the second paradigm, animals were placed for a brief period of time into a new, wired cage resulting in vibrissae stimulation when they explored the new environment. Both approaches induced c-Fos expression in barrel cortex corresponding to the stimulated vibrissae, especially in layer IV. Layers II/III and V/VI also showed c-Fos induction, but there were no detectable changes in layer VIb. The majority of c-Fos-expressing cells are probably not inhibitory neurons, because they do not show parvalbumin staining. Both paradigms, in contrast to the previous methods, are simple to use and do not require anesthesia, restraint of animals, or elaborate experimental setups.

Animals↗