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J Kazimierczak

Publications and source records attributed to J Kazimierczak.

At least 19 recordsLinked to original sources
PubMed1986

Carbonic anhydrase activity in primary sensory neurons. I. Requirements for the cytochemical localization in the dorsal root ganglion of chicken and mouse by light and electron microscopy.

Subpopulations of primary sensory neurons in mammalian dorsal root ganglion (DRG) exhibit carbonic anhydrase (CA) activity. To identify these subpopulations in DRG cells of mouse and chicken, the reliability of the cytochemical localization of the enzyme requires that several conditions be fulfilled: Preservation of the enzyme activity in glutaraldehyde-containing fixative; accessibility of the cytoenzymatic reaction throughout 20-micron thick Vibratome sections; retention of the reaction product in situ during OsO4 post-fixation; specificity of the cytoenzymatic reaction for CA activity as corroborated by the immunocytochemical detection with antibodies anti-CA II in mouse DRG; strict correlation between the CA activity and the cytological characteristics in a given subclass of neurons. On the basis of these criteria, it is concluded that the CA activity may be used as a cell marker to identify cytologically defined neuronal subpopulations and their axons in mouse DRG. In chicken DRG, CA activity is not consistently expressed in a given subclass of ganglion cells and their axons. Hence, it is assumed that the expression of CA activity by DRG cells in chicken is modulated by functional or environmental conditions.

Animals↗
PubMed1986

Carbonic anhydrase activity in primary sensory neurons. II. Influence of environmental factors on the phenotypic expression of the enzyme in dissociated cultures of chicken dorsal root ganglion cells.

Neuronal subpopulations of dorsal root ganglion (DRG) cells in the chicken exhibit carbonic anhydrase (CA) activity. To determine whether CA activity is expressed by DRG cells maintained in in vitro cultures, dissociated DRG cells from 10-day-old chick embryos were cultured on a collagen substrate. The influence exerted by environmental factors on the enzyme expression was tested under various conditions of culture. Neuron-enriched cell cultures and mixed DRG-cell cultures (including numerous non-neuronal cells) were performed either in a defined medium or in a horse serum-supplemented medium. In all the tested conditions, subpopulations of cultured sensory neurons expressed CA activity in their cell bodies, while their neurites were rarely stained; in each case, the percentage of CA-positive neurons declined with the age of the cultures. The number and the persistence of neurons possessing CA activity as well as the intensity of the reaction were enhanced by addition of horse serum. In contrast, the expression of the neuronal CA activity was not affected by the presence of non-neuronal cells or by the rise of CO2 concentration. Thus, the appearance and disappearance of neuronal subpopulations expressing CA activity may be decisively influenced by factors contained in the horse serum. The loss of CA-positive neurons with time could result from a cell selection or from genetic repression. Analysis of the time curves does not support a preferential cell death of CA-positive neurons but suggests that the eventual conversion of CA-positive neurons into CA-negative neurons results from a loss of the enzyme activity. These results indicate that the phenotypic expression of cultured sensory neurons is dependent on defined environmental factors.

Acetylcholinesterase↗
PubMed1985

Neuronal subpopulations in the dorsal root ganglion of the mouse as characterized by combination of ultrastructural and cytochemical features.

The neuronal population of dorsal root ganglia in mouse consists of various classes of ganglion cells which may be divided in turn into subclasses by using several criteria. In class A cells, membrane-bound organelles are distributed ubiquitously throughout the large perikarya. Subclass A alpha (12%), which is characterized by large clumps of Nissl substance separated by narrow strands of neuroplasm, lacks detectable carbonic anhydrase activity. Subclass A beta (16%) displays small clusters of Nissl substance isolated by broad channels of neuroplasm and a moderate activity of carbonic anhydrase. Subclass A gamma (8%) shows the most intense carbonic anhydrase activity and a lack of uptake for [3H]L-glutamine. In class B cells (63%), the small perikarya display a zonal distribution of the organelles. Subclass B alpha contains parallel cisternae of rough endoplasmic reticulum and acid phosphatase isoenzymes present in long and curved Golgi saccules. Subclass B beta displays straight Golgi saccules rich in acid phosphatase isoenzymes and a high affinity uptake for glutamine. Subclass B gamma is characterized by the absence of acid phosphatase isoenzymes and by the presence of substance P-immunoreactivity. Class C cells (1%) have the smallest size and the highest affinity uptake for glutamine. Thus subtypes of primary sensory ganglion cells may be identified by the concomitant use of multiple criteria.

Acid Phosphatase↗
PubMed1980

A study of scanning (SEM) and transmission (TEM) electron microscopy of the glomerular capillaries in developing rat kidney.

Kidneys of 2 to 10 day-old rats of Wistar and Sprague-Dawley strains were fixed with glutaraldehyde by retrograde vascular perfusion and then prepared for observation in TEM and SEM. In addition methacrylate casts of differentiating glomerular capillaries were examined by SEM. Although the glomerular vascular pattern differs from one glomerulus to another, its differentiation proceeds according to the following general plan. First the glomerular capillary splits longitudinally, finally to form 3 to 5 lobules consisting of a capillary network, sustained centrally by the mesangium. In the present study the differentiation of glomerular capillaries is described in five successive arbitrarily selected stages. At Stage I a capilllary loop penetrates between the lower limb and the middle segment of the S-shaped body, the rudimentary nephron. At Stage II the capillary undergoes a first subdivision, establishing the primitive lobulation of the glomerulus. At Stage III the vascular and urinary poles differentiate. At Stage IV the glomerulus assumes the aspect of a spherical body, and the capillaries in each lobule undergo subdivision. In Stage V the glomerular vascular pattern approaches its adult appearance, although the maturation processes continue for an extended period of time. Hence in the 10 day-old rat the best-differentiated glomeruli are half the size of adult glomeruli, and their capillary loops are proportionally less well-developed. The capillaries of adjacent lobules may communicate with each other, but a direct vascular shunt between the afferent and efferent vessels cannot be demonstrated.

Animals↗
PubMed1980

Scanning electron microscopy of the developing renal glomerulus.

The constant progress in histological technology opens up new possibilities in morphogenetic research, particularly when a three-dimensional picture is desirable. In the present study a retrograde vascular fixation, methacrylate casts of blood vessels and scanning electron microscopy have been used to reconsider the earlier observations on the development and differentiation of the renal glomerulus in the kidney of the new-born rat.

Aging↗
PubMed1976

Morphometric and enzyme histochemical behaviour of the kidney of young rats before and after unilateral nephrectomy.

Four week old male Wistar rats were unilaterally nephrectomized, and one, two, four, fourteen, and twenty-eight days after the operation the remaining kidneys were removed for morphological examination--including measurement of diameters of the tubules--and for histochemical investigation of enzymatic activities in the nephrons. The following enzymes were examined: succinate DH, lactate DH, alpha-glycerophosphate DH, isocitrate DH, glucose-6-phosphate DH, cytochrome oxidase, adenosine triphosphatase, alkaline and acid phosphatases. In comparison with kidneys of control animals of the same age and sex, the hypertrophy of the remaining kidney was found to be, even in these young rats, entirely due to enlargement of preexisting nephrons. The measurements have indicated that the hypertrophy was most distinct between the second and fourth day after uninephrectomy. Four weeks after the operation the diameters of proximal and distal tubules were about 21% and 18% respectively bigger in the uninephrectomized animals than in the corresponding controls. This increase in size was accompanied by some changes in intensity of enzymatic staining reactions; after an initial diminishment, a graduate increase in activity of almost all the observed tubular enzymes was found; this seems to be the expression of the functional compensation by the remaining kidney.

Adaptation, Physiological↗
PubMed1976

[Development of the renal glomerulus examined by transmission and scanning electron microscopy].

The kidneys of 2 to 10 days old albino rats were fixed by perfusion and examined by transmission and scanning electron microscopy. Furthermore, vascular casts of renal vessels in rats of the same ages were effectuated by injection of methacrylate into the aorta and observed by SEM. The observation of glomerulogenesis in different stages has indicated that the glomerular capillaries originate in the interstitial vessels which penetrate into the cleft formed in the wall of the renal vesicle. Initially the capillaries have an aspect of small sinusoids which then expand peripherally and undergo successive subdivisions: the anastomosis in each glomerular lobule persists. The podocytes originate from the cells of the renal vesicle facing the penetrating capillaries. The initially primitive cells branch off successively and extend around the expanding capillaries with their small processes -- the foot processes which interdigitate with the corresponding structures of the neighbour cells.

Age Factors↗
PubMed1976

[Modification of the number and structure of certain cytoplasmic components of the renal tubules during compensatory hypertrophy].

In the remaining kidney of unilaterally nephrectomised three to six months old Wistar rats, the measurement of the external and internal diameters indicated an increase in size of both proximal and distal convoluted tubules, although less distinct in the latter. Stereomorphometric measurements of the chondriome and the cytoplasmic inclusions (lysosomes, phagosomes, peroxisomes, etc.) have shown, as compared with similar tests in shamoperated animals, changes in the volumes of these components which can be related to the increase of enzymatic activities reported earlier. However, no obvious changes of the general ultrastructure of the kidneys undergoing hypertrophy could be observed.

Animals↗