Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SALTS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39Linked to original sources

Body sodium in rats: response to DOCA, adrenalectomy, changes in salt intake, and a salt load.

Body Na was studied by an isotope method in rats on Na-free diet plus a choice of H2O and 0.5% or 0.1% NaCl. Two groups (1 on 0.5%, 1 on 0.1% NaCl) had Silastic deoxycorticosterone acetate (DOCA) implants, two similar groups were sham operated, and a fifth group (on 0.5% NaCl) underwent adrenalectomy (ADX). Saline consumption increased in DOCA-treated and ADX rats. Body Na was increased by DOCA and by drinking 0.5% NaCl compared with 0.1% NaCl. Body Na after intraperitoneal NaCl loading (which raised body Na 8-10%) and withdrawal of NaCl drinking fluids was analyzed by use of the model y = Ae-a(t-d) + Be-bt, where y is body Na at time t and d is delay before fast rate constant a is established; d was greater on the lower Na intake. Rate constant a was not reduced by chronic DOCA treatment. Coefficient B of the slow exponential, representing the basal level to which body Na falls on zero Na intake, and equivalent to Hollenberg's "set-point," was higher in DOCA-treated rats. This analysis makes use of Hollenberg's set-point concept, but the findings suggest that the set-point is related to mineralocorticoid activity and is thus presumably variable.

Adrenalectomy↗

High-NaCl diets increase natriuretic and diuretic responses in salt-resistant but not salt-sensitive SHR.

This study tested the hypothesis that NaCl-sensitive spontaneously hypertensive rats (SHR-S) display a defect in natriuretic and diuretic responses to acute volume loading that contributes to the rise in arterial pressure observed when the rats are fed a high-NaCl diet. Seven-week-old SHR-S and NaCl-resistant SHR rats (SHR-R) and normotensive (Wistar-Kyoto and Sprague-Dawley rats) were fed high- or basal NaCl diets. After 2.5 wk on the diets, preinstrumented conscious rats received an intravenous infusion (5% body wt; 0.5 ml/min) of isotonic saline, and urine was collected through a bladder catheter for 90 min. Control rats on the high-NaCl diet (compared with basal) excreted a significantly greater percentage of Na+ and volume load. In contrast, SHR-S on high-NaCl diet (compared with basal) had a very small increase in natriuretic response and no increase in diuretic response to volume expansion. The effect of renal denervation on natriuretic and diuretic responses to volume load was tested. In SHR-R on 1 and 8% NaCl diets, renal denervation had little or no effect on these responses, suggesting that renal nerves do not play a prominent role in the dietary NaCl-induced increases in the natriuretic and diuretic responses to volume load. These results demonstrate that NaCl-resistant rats rapidly adapt to diets high in NaCl content with increased natriuretic and diuretic responses to acute volume loading. The failure of SHR-S to adapt to the dietary challenge may result in volume loading and a secondary increase in arterial pressure after feeding.

Animals↗

Fetal bile salt metabolism. The intestinal absorption of bile salt.

The intestinal absorption of sodium taurocholate was studied in the near-term fetal and neonatal dog. Absorption rates were measured in vivo in isolated loops of fetal jejunum and ileum. Absorption was also measured in vitro in everted sacs and rings of fetal and neonatal jejunum and ileum. The maximal rates of taurocholate absorption observed after instillation of 1 micronmol taurocholate into closed segments of fetal jejunum and ileum with intact blood supply were not significantly different (P less than 0.2), and equalled 0.282+/-0.026 (mean+/-SEM) and 0.347+/-0.051 micronmol/h per 10-cm segment length jejunum and ileum, respectively. Similarly, the rates of absorption from open segments of jejunum and ileum perfused with 0.4 and 1.0 mM taurocholate were nearly identical (0.232+/-0.040 and 0.255+/-0.039, respectively at 0.4 mM, and 0.470+/-0.065 and 0.431+/-0.013, respectively at 1.0 mm) (P greater than 0.2). At perfusate concentrations of 4.0 mM, moreoever, jejunal absorption exceeded ileal absorption (1.490+/-0.140 and 0.922+/-0.200, respectively (P less than 0.05). As expected, concentration of taurocholate by the mucosa was readily demonstrated in adult ileal, but not in adult jejunal everted rings. In contrast, there were no significant differences in mucosal uptake of taurocholate by fetal jejunal and ileal rings. Fetal ileal mucosal concentrations were not significantly above those in the incubation medium after 1-h exposure of the mucosa to 0.003, 0.03, and 0.3 mM taurocholate. Uptake was proportional to incubation medium concentration over the full range of values. This was also true of tissues from 1-wk-old neonates. However, by 2 wk of age, ileal mucosal concentration of taurocholate was evident and adult levels were attained by 5 wk of age. It is concluded that taurocholate is absorbed by the fetal gut and that ileal absorption is no more efficient than jejunal absorption. Although active glucose transport was demonstrable in both jejunum and ileum, it was not possible to demonstrate an ileal mechanism for active transport of taurocholate in the fetus. Active ileal transport was not demonstrable in the newborn until at least 2 wk after birth.

Age Factors↗