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Biomedical subjects

H S Moreno

Publications and source records attributed to H S Moreno.

5 recordsLinked to original sources

Severe hyperglycemia: a determinant factor for hypofiltration in alloxan diabetic rats.

The relationships among glomerular filtration rate, renal plasma flow and extracellular fluid volume were investigated in control and severely hyperglycemic (442+/-33 mg/dl) untreated, alloxan diabetic ats. Most of diabetic animals showed significant lower values of inulin clearance (diabetics, 0.55+/-0.07 ml/min.100 g; controls, 0.97+/-0.04) and p-aminohippurate clearance (diabetics, 2.11+/-0.39 ml/min.100 g; controls, 3.93+/-0.25). Diabetic rats exhibited reduced efficiency in tubular Na(+) reabsorption, increased urinary Na(+) excretion (diabetics, 3.12+/-0.27 mEq/day; controls, 1.25+/-0.14) and diminished values of plasma renin activity (diabetics, 3.34+/-0.44 ng/ml.h; controls, 8.64+/-0.79). Significant negative correlations were found between glycemia and renal hemodynamic variables. Acute overload with glucose further decreased these variables in both groups: inulin clearance in diabetics vs. controls, 0.26+/-0.04 vs. 0.44+/-0.05 ml/min.100 g; p-aminohippuric acid clearance in diabetics vs. controls, 1.09+/-0.20 vs. 1.55+/-0.21 ml/min.100 g. We conclude that chronically hyperglycemic alloxan diabetic rats showed diminished glomerular filtration rates (inulin clearance), renal plasma flow ( p-aminohippurate clearance) and extracellular fluid volume associated with urinary Na(+) losses and alterations in the renin-angiotensin system. Decreased renin-angiotensin system activity might reduce aldosterone secretion, which in turn could result in (successively) urinary sodium loss, extracellular fluid volume contraction and reductions in glomerular filtration and renal plasma flow.

Animals↗

Infection with Trypanosoma cruzi during pregnancy in rats and a decrease in chronic myocardial lesions in their infected offspring.

To ascertain whether maternal infection with Trypanosoma cruzi may influence the course of the parasitic infection in offspring, two groups of female 1 rats were mated with syngeneic sires. One group of females was infected with 10(6) trypomastigotes of T. cruzi three times at weekly intervals. All offspring were nursed by their mothers until weaning and then separated into two groups of young, one to be infected with the same dose of T. cruzi, and the other to remain uninfected. Infection of pregnant rats caused no aggravated disease but resulted in a self-controlled infection that did not cause any deaths or affect their reproductive capacity. The number of young delivered, litter size, fertility coefficient, and offspring weights at weaning were also unaffected by maternal infection; however, the survival coefficient decreased in comparison with values recorded in the offspring of uninfected mothers. The latter finding is likely due to neonatal transmission, since bloodstream forms of T. cruzi were observed in a few offspring of infected mothers. While infected offspring whose mothers had been inoculated with T. cruzi during pregnancy were not protected from acute infection, the occurrence of chronic focal myocarditis was less prevalent when compared with that recorded in chronically infected offspring born to uninfected mothers.

Acute Disease↗

Depressed adjuvant arthritis in rats transferred with spleen cells from Trypanosoma cruzi-infected syngeneic donors.

In the present study we investigated whether the attenuating effect of chronic Trypanosoma cruzi (Tc) infection on adjuvant arthritis (AA) in the rat could be transferred to naive recipients. Transfer of whole spleen cells, but not of serum, from Tc-infected rats reduced AA (means +/- SEM: 11 +/- 0.5) in recipient animals (control values, means +/- SEM: 19 +/- 0.7). Transfer of a T-cell-enriched subpopulation from spleen cells of Tc-infected rats (obtained by filtration through a nylon wool column) resulted in a similar attenuation of AA (means +/- SEM: 7.5 +/- 2.2). The arthritic response of rats intraperitoneally inoculated with 2 x 10(5) Tc 48 h before induction did not differ from that observed in controls. Neither parasites nor specific antibodies were observed in suckling mice inoculated with serum or cell suspensions employed in transfer experiments. Consequently, the depressive effect on AA could not be directly attributed to Tc per se. We hypothesize that a homeostatic immunosuppressor mechanism may be responsible for this phenomenon.

Animals↗