Cytofluorometric study of the erythrocyte glycoconjugates content in different species of vertebrates.

The PAS-positive material was measured by cytofluorometry in peripheral circulating erythrocytes of 22 species from different classes of Vertebrates. The following parameters were considered: total fluorescence intensity per cell, concentration index, fluorescence fading. The highest variability of concentration indexes was found in Fishes with a minimum in the more active swimmers (Scylliorhinus and Salmo); this fact may be related to a more intense erythropoiesis. The values were more homogeneous in the Amphibians, Reptiles, and Birds, the difference never exceeding 1/2 between the maximum and minimum values. The lowest concentration indexes were found in Mammals, a class with very specialized and enucleated erythrocytes: the data appear rather heterogeneous with a minimum in Macaca. The patterns of fluorescence fading suggest a biochemical homogeneity of the PAS-positive erythrocyte material in the species considered. This fact might indicate the presence of a fundamental biochemical component possibly linked to different structures of the red cells.

Biochemical and histochemical features of human cultured cells (EUE) adapted to hypertonic medium.

EUE cells from a human heteroploid line cultured in hypertonic medium (0.274 M NaCl) modify their lipid pattern: sulfolipid concentration reaches 86 to 90 microgram/mg protein whilst it ranges between 19 to 32 microgram/mg in cells cultured in isotonic medium. Ganglioside concentration reaches 2.6 nmoles of sialic acid/mg protein (after 75 days) and 13 (after 85 days) in hypertonic saline medium. Whilst it is 0.5 in isotonic medium. Phospholipid concentration does not show any similar change. Cytoenzymatic analysis reveals that dehydrogenases (lactate, G-6-P dehydrogenases, tetrahydrofolate reductase and NADH diaphorase) appear strongly enhanced in cells grown on hypertonic medium. On the contrary higher acid phosphatase and ATPase activity was demonstrable in cells grown on isotonic medium. These results are similar (except for ATPase activity) to those observed in salt secreting glands involved in strong osmotic work. The results are discussed in relation to the problem of energy supply in cells performing osmotic work.

An ultrastructural and cytochemical study of the mesonephros of Rana esculenta during activity and hibernation.

The biological cycle of most amphibians undergoes seasonal variations. In this study, we investigated the mesonephros of Rana esculenta during active life and the natural hibernation period. The ultrastructural morphology of the different tracts constituting the nephron was analysed. Moreover, to evaluate the effect of seasonal temperature variations on the mesonephros function, the activity of some enzymes linked to membrane transport and playing regulatory roles in various metabolic pathways was investigated in different tracts of the frog nephron. During hibernation the glomerular filtration barrier appeared thicker than in the active life, lysosomes and paraplasmatic material, mostly glycogen, being accumulated in the proximal and distal tubule cells respectively. Cytoplasmic organelles, i.e., mitochondria, endoplasmic reticulum were observed in segregated areas. At the same time, changes in some enzyme activities were noted. The activity of some membrane-transport enzymes (5' nucleotidase and K+-p-nitrophenyl phosphatase) and of energetic metabolism (succinic dehydrogenase) was reduced. Nevertheless the alkaline phosphatase activity was not changed significantly, and this suggests that some metabolic activities were preserved in the hibernating samples. These results indicate morpho-functional adaptations of the kidney cells that preserve their role in osmoregulation and some metabolic processes, even during unfavourable seasons.

Cytochemical characterization of the hemocytes of Leucophaea maderae (Dictyoptera: Blaberoidea).

A correlated morphological and cytochemical approach to the hemocytes in Leucophaea maderae characterizes the granule contents of blood cells with May Grunwald-Giemsa (MGG), periodic acid-Schiff (PAS), Alcian blue (AB), and Sudan black B stainings, and after fluorochroming with acridine orange (AO). The cell nucleus and nuclear DNA is demonstrated with the Feulgen reaction. The activities of α-naphtyl butyrate esterase (ANBE) and acid phosphatase (AcPase) have been investigated in hemocytes, by both light and electron microscopy. The study discloses five cells types: prohemocyts, plasmatocytes, granulocytes, spherulocytes, and cytocytes. Occasional Sudan black-positive cells could represent an adipohemocyte category. The different patterns of cytochemical staining suggest a variety of functional roles for hemocytes. The most selective reaction pattern in terms of cytological differentiation among hemocytes occurred with the ANBE reaction. Ultrastructural analysis of intercellular granule contents, and the demonstration of cells with intermediate features, suggests that the hemolymph of Leucophaea maderae contains a developmental series from prohemocyte to plasmatocyte to granulocyte and then to spherulocyte. © 1993 Wiley-Liss, Inc.