Effects of long-term oral L-arginine on esophageal motility and gallbladder dynamics in healthy humans.
Inhibitory nitrergic neurons are known to play a role in the regulation of motility patterns of the distal esophagus, the lower esophageal sphincter (LES), and the gallbladder. Our study aim was to investigate the effects of "long-term" (i.e., prolonged) oral intake of L-arginine (L-Arg), the endogenous source for nitric oxide (NO) synthesis, on postprandial LES pressure (LESP), esophageal motility, gastroesophageal reflux, and gallbladder motility. L-Arg (30 g/day) or glycine (placebo; 13 g/day; isosmolar) was given orally to 10 healthy male volunteers for 8 days, according to a randomized, crossover design. Twenty-four-hour urinary nitrite/nitrate excretion was measured to indicate NO synthesis. Basal early postprandial LESP was lower after L-Arg ingestion (2.2 kPa) than after glycine ingestion (2.7 kPa) (P < 0.05). L-Arg abolished the physiological late postprandial rise in LESP. Transient LES relaxations were longer lasting after L-Arg ingestion (P < 0.02). Esophageal motility and reflux were not affected (not significant). Fasting and residual gallbladder volumes were greater after L-Arg ingestion (P < 0.05). Urinary nitrite/nitrate excretion was higher after L-Arg intake (P < 0.05). In conclusion, long-term oral L-Arg suppresses late postprandial LESP increase, prolongs transient LES relaxations, and increases fasting and residual gallbladder volumes. These effects may be mediated by increased NO synthesis.
Luiking
Y C
YC
Department of Surgery, University Hospital Utrecht, Utrecht, The Netherlands.
Weusten
B L
BL
Portincasa
P
P
Van Der Meer
R
R
Smout
A J
AJ
Akkermans
L M
LM
D000328:Adult; D000596:Amino Acids / Q000097:blood; D001120:Arginine / Q000008:administration & dosage*; D004311:Double-Blind Method; D004573:Electrolytes / Q000097:blood; D004943:Esophagogastric Junction / Q000187:drug effects / Q000502:physiology; D004947:Esophagus / Q000187:drug effects* / Q000502:physiology*; D005215:Fasting; D005502:Food; D005704:Gallbladder / Q000000981:diagnostic imaging* / Q000187:drug effects*; D005764:Gastroesophageal Reflux; D006801:Humans; D008297:Male; D008365:Manometry; D009569:Nitric Oxide / Q000096:biosynthesis / Q000652:urine; D010919:Placebos; D014463:Ultrasonography; D014508:Urea / Q000097:blood
D000596:Amino Acids; D004573:Electrolytes; D010919:Placebos; D009569:Nitric Oxide; D014508:Urea; D001120:Arginine