Bombesin-like peptides in the enteric plexuses

SATION OF GRP-LIKE IMMUNOREACTIVIT~ 2 ~llen , C.F. Johnston, R.F. M u r p h y ochemistry, The Queen's University iomedical Sciences, The University mrse phase HPLC we have identified ic lymphatics. Extracts and chror erum was raised to neuromedin C (( cts by 46% with whole molecule po: GRPIO. Bovine lymphatics (1.3 g) air. An aliquot of the extract Bondapak reverse phase column. F • The level of immunoreactivity i ght. Chromatographic characterisation of the extra extract indic~ ch co-eluted with the synthetic GRPI0 standard. A second pe likely to be oxidised product formed during the drying dry: proce ~hatic smooth muscle is sparsely innervated and is known to s data may indicate that GRPIO may have a role in this t tiss~ lulator of adrenergic activity.

MESENTERIC LYMPHATICS uchanan

ed GRP-like immunoreactivi fractions were assayed usi gated to ovalbumin. In t 5% with GRP14-27 and 6% wi ted in acidified ethanol a for assay and the remaind 1 ml were dried under vacu tic extract was i.I ng/g w or peak of immunoreactivi ch earlier than GRPI0 and covery was greater than 90 idrenaline as a transmitte nd neurotransmitter or as

B O M B E S I N - L I K E PEPTIDES IN IN THE ENTERIC PLEXUSES. J.B. Furness, A.S. Miller and M. Costa, istralla 5042. Anatomy & Histology and of Physiology, Medical School, Flinders University, Australi

Departments

Bombesin-like peptides havee been located immunohistochemlcally in nerve cells and fibres throughout In enteric neurons, the bombesi! )ombesin-like peptides app~ alimentary tract in a rangee of mammalian species. to be the whole molecule orr fragments of gastrin releasing peptide (GRP). We have studied two aspects neurons in the guinea-] enteric neurons with GRP immunore [mmunoreactlvity oreactlvit~ (GRP-IR): the projections of such neur small intestine and the distribu distribution ibution of GRP-IR in the gulnea-pig, rat, dog and human stomadh, -containing endocrine cell particular emphasis on the relation between GRP-IR nerve fibres and gastrin-contaJ In the gulnea-pig small i n ttestlne, e s t i n e nerve fibres with GRP-IR in the circular muscle arise from cell bod Myenteric nerve cell bodies in the small intestine also provide projections in the myenteric ganglia. Those fib submucous ganglia, to more anally located myenteric ganglia, and to the coeliac ganglion. ga dynorphin, enkephalln that run to the coellac ganglion are also reactive for cholecystokinin, nerve o vasoactive intestinal peptide. The fibres in the coeliac ganglion end around noradrenerglc noz blood f L ity and secretion, but not around those that control intestinal i bodies that control motilit, astric wall, reactive ne mely rare in the small intestinal mucosa. In the gastrit Reactive fibres were extremel Tenteric plexus, the mus cells were found in the myenteric ganglia and nerve fibres were in the myenter: Lrterioles It is presumed that the reactive fibres in layers, around submucous arteriol ioles and in the mucosa. les in the myenteric ganglia. The mucosal fibres were found in the gast muscle come from cell bodies aining endocrine cells were abundant, and in similar or greater density in antrum, where gastrin-contalnin astrin cells are approac] void of gastrin cells. A low proportion of antral gastri oxyntic mucosa which is devoid utions of those fibres -LI nerve fibres and furthermore the frequency distrlbutio to within 2 microns by GRP-LI of the gastrin cells throu ~gh the mucosal thickness are in general not coincidental; ; the peak density sstrin cell density. ser to the basal mucosa than is the region of maximum gas GRP-LI nerve fibres is closer blood vessels ~ed from the nerve fibres reaches the gastrin cells via mucosal mu is possible that GRP released

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