Effect of 17-norleucine-vip on gastro-duodenal motility relative to
serum vip concentration and blockade of nitric oxide synthase.
Holle, G. E., E. Steinbach, E. W[umlaut]unsch, J. J. Holst.
Gastroenterol. Research Laboratory, L.M.Univ., Max Planck Inst. f.
Peptide Chemistry, Munich Federal, R.Germany, Panum Inst. f. Med.
Physiology, Copenhagen, Denmark
APStracts 2:0090G, 1995.
Mechanical and electrical activity in the antrum, pylorus and duodenum
was evaluated in the conscious dog, instrumented with seven strain
gauges and five platinum electrodes. Norleucine-vasoactive intestinal
peptide (VIP) or Norleucine-VIP plus L-NAME was injected
intraarterially close to the pylorus to identify influences of Nitric
oxide on effects of VIP. VIP concentrations were measured by
radioimmunoassay in serum samples collected from the cubital and
portal veins before and up to 2 h after VIP. VIP (0.004 - 0.006
mg/kg/10min) abolished phasic contractions in the interdigestive
state for 16.8 min and in the digestive state for 14.4 min while
whole serum VIP concentration rose above 42.4 pmol/1 + 13.
Administration of L-NAME did not significantly influence the effects
of VIP. After effects of VIP consisting of a reduced motility index,
lasted 33 +/- 10.6 min in the interdigestive state and 44.5 +/- 42
min in the digestive state. This VIP-after effect in the
interdigestive state was shortened in time by the addition of L-NAME.
The results overall suggest that nitric oxide release is a factor
only in the after effects of VIP.
Received 7 December 1994; accepted in final form 20 March 1995.
APS Manuscript Number G477-4.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 9 May 1995.