Calcium absorption or secretion by rat ileum in vitro: effects of dietary calcium intake

Acute effect of ethanol on intestinal calcium transport.

“…It has been reported that the ileum is unresponsive to 1,25(OH)2D3 (22)(23)(24)(25) and is likely to act only in the nonsaturable transport of calcium. On the other hand, evidence for the existence of active calcium absorption has also been reported (4,5,26). In the present study net absorption of calcium was observed in the ileum at a luminal calcium concentration (0.9mM) lower than the plasma ionized calcium concentration although at a rate lower than that occurring in the duodenum.…”

“…Since calcium can also be actively absorbed (3)(4)(5)(6) and secreted in the ileum (4,(6)(7)(8) and the effect of ethanol on ileal calcium transport in rats has not been studied, the present ex periments thus aimed to investigate the acute effects of intragastric administration of ethanol on net fluid and calcium absorption in vivo and by using an in situ intestinal loop technique to quantitate the calcium fluxes in the duodenum and ileum.…”

Calcium and Inorganic Phosphate Transport in Rat Colon

“…tion of both Ca and Pi (1). Our data show that 1,25-(OH)2D3 induces a saturable active absorptive process for Ca in colon with an apparent Km of 0.9 mM, which is similar to those estimated for rat duodenum, (7) and ileum (15). This suggests that the colonic cells which transport Ca may have the same 1,25(OH)2D3-stimulated process as their small intestinal counterparts and provides a persuasive argument for the existence of Pi-independent Ca-transporting cells in the small intestine (7,16 (19,20).…”

Calcium and inorganic phosphate secretion of rat ileum in vitro

“…The ileum was chosen for study because of focusing on secretory transport which is known to occur in this gut segment [6,31,34,35,37]. The experimental conditions investigated were characterized by moderately, not significantly depressed 1,25 (OH)2D3 levels in NPX rats and low concentrations after EHDP treatment.…”

“…D3 or 1,25 (OH)2D3 status of the animals [12,17,31,[33][34][35][36][37]; gut segments investigated included duodenum, jejunum, ileum as well as colon. D3 or 1,25 (OH)2D3 status of the animals [12,17,31,[33][34][35][36][37]; gut segments investigated included duodenum, jejunum, ileum as well as colon.…”