Urinary solute transport by ileal segments. I. Effects of nicotinic acid.
This study was conducted to quantify urinary solute transport by the ileum, using an in vivo human model, and to determine the effect of nicotinic acid on this process. Patients were studied under both basal conditions and niacin therapy. The rates of solute transport were established by analysis of excretion indexes for each solute. Potassium and ammonium were absorbed by the ileum, while phosphorus, sodium and bicarbonate were secreted. The percentage excretion index of sodium and bicarbonate increased by approximately 100 and 600% respectively, causing a significant rise in urinary pH. Although not statistically significant, there was a tendency for chloride to be absorbed and for water to pass into the bowel lumen. Nicotinic acid 3 g/day had no significant effect on urinary solute transport.
Martínez-Piñeiro
L
L
Department of Urology, La Paz Hospital, Madrid, Spain.
Mateos
F
F
Montero
A
A
Madero
R
R
Martínez-Piñeiro
J A
JA
D000641:Ammonia / Q000652:urine; D001639:Bicarbonates / Q000652:urine; D001693:Biological Transport, Active / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007082:Ileum / Q000378:metabolism* / Q000601:surgery; D007408:Intestinal Absorption / Q000187:drug effects; D009539:Nicotinic Acids / Q000494:pharmacology*; D010758:Phosphorus / Q000652:urine; D011188:Potassium / Q000652:urine; D012964:Sodium / Q000652:urine; D014547:Urinary Diversion
D001639:Bicarbonates; D009539:Nicotinic Acids; D010758:Phosphorus; D000641:Ammonia; D012964:Sodium; D011188:Potassium