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.
Department of Surgery, University Hospital Utrecht, Utrecht, The Netherlands.
Y C
YC
Luiking
B L
BL
Weusten
P
P
Portincasa
R
R
Van Der Meer
A J
AJ
Smout
L M
LM
Akkermans
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