Peristalsis abolishes the release of methionine-enkephalin from guinea-pig ileum in vitro.

  title={Peristalsis abolishes the release of methionine-enkephalin from guinea-pig ileum in vitro.},
  author={S. J. Clark and T. W. Smith},
  journal={European journal of pharmacology},
  volume={70 3},
The release of methionine-enkephalin from superfused guinea-pig ileum has been demonstrated. Methionine-enkephalin, as measured by radioimmunoassay, was shown to be released from tissues maintained at an intraluminal pressure of O cm water (resting conditions). Increased intraluminal pressure (5 cm water) induced peristalsis and abolished the release of methionine-enkephalin. These results provide further evidence that endogenous opioids may be involved in the modulation of contractile activity… Expand
The release of Met-enkephalin from the guinea-pig ileum at rest and during peristaltic activity.
Segments of guinea-pig ileum maintained at an intraluminal pressure of 0cm H2O released methionine-enkephalin-like material (ME) into the bathing fluid and results suggest that ME release is associated with nonpropulsive activity in the gu Guinea-p pig ileu. Expand
Short-term nerve stimulation increases enkephalin production and content in the guinea pig myenteric plexus
The results indicate that tissue levels of enkephalin are not fixed but can fluctuate in response to nerve stimulation and suggest a mechanism whereby the rate of production of this opioid peptide is coupled to neuronal activity. Expand
Meal-stimulated release of methionine-enkephalin into the canine jejunal lumen.
It is concluded that met-enkephalin is present in the jejunal lumen, and that luminal release of this opioid is augmented by a meal. Expand
Reflex peristalsis in the guinea pig isolated ileum is endogenously controlled by kappa opioid receptors
  • W. Kromer
  • Biology, Medicine
  • Naunyn-Schmiedeberg's Archives of Pharmacology
  • 2004
It is concluded that predominantly ξ opioid receptors are used by endogenous opioids under the present conditions to inhibit reflex peristalsis. Expand
Separation of enkephalin-degrading enzymes from longitudinal muscle layer of bovine small intestine. Enzyme inhibition by arphamenine A.
Arphamenine A, a new potent inhibitor for aminopeptidase B, was shown to be a useful compound in inhibiting all of the enkephalin-degrading enzymes in small intestine. Expand
Differential effects of SKF 10,047 (N-allyl-normetazocine) on peristalsis and longitudinal muscle contractions of the isolated guinea-pig ileum
It is concluded that μ- and ϰ-opioid receptors are of a greater functional significance than σ-receptors in the control of peristalsis. Expand
Release of dynorphin, somatostatin and substance P from the vascularly perfused small intestine of the guinea‐pig during peristalsis
Results indicate that dynorphin‐(1–17), somatostatin and substance P may be transmitters involved in the coordination of the peristaltic reflex and part of the inhibitory effects of opioid peptides and noradrenaline on intestinal motility may be brought about by inhibition of the release of substance P. Expand
Opiates induce long-term increases in prodynorphin-derived peptide levels in the guinea-pig myenteric plexus
Using a monoclonal antibody (3-E7), which recognizes virtually all endogenous opioid peptides, it was found that levels of higher molecular material were also increased upon opiate challenge, suggesting that a single dose of an exogenous opiate results in an increase in peptide synthesis. Expand
Regulation of Intestinal Motility by Peripheral Opioids: Facts and Hypotheses
The present chapter will therefore focus on intestinal mechanisms controlling motility, and provide a background for integration of available observations on opioids. Expand
Intestinal peristalsis associated with release of immunoreactive substance P
The findings indicate that intestinal peristalsis is associated with the release of substance P from enteric neurones, which is likely to be a neurotransmitter involved in the coordination of the peristaltic reflex. Expand


Summary The myenteric plexus-longitudinal muscle preparation of guinea-pig ileum was shown to contain at least one peptide, in the molecular weight range of 10,000 to 20,000 daltons, which on trypticExpand
Unexpected reversal effects of naloxone on the guinea pig ileum.
The results indicate that during fatigue a substance is liberated which blocks peristalsis and suggests that naloxone-induced reversal of inhibition in the guinea pig ileum does not necessarily demonstrate that the inhibition is caused by a direct action on morphine receptors. Expand
Endogenous opiate receptor ligand: electrically induced release in the guinea pig ileum.
The electrically induced activation of the opiate receptors was produced by a prolonged simulation at 10 hertz and provides the first evidence that an endogenous opiate receptor ligand is released by nerve stimulation. Expand
Incorporation of labelled amino acids into the enkephalins
The aim of this study was to develop a procedure for studying the biogenesis of the enkephalins and to test the hypothesis that these peptides are derived from larger precursors via ribosomal synthesis and subsequent proteolytic cleavage of the precursor protein. Expand
Immunohistochemical studies using antibodies to leucine-enkephalin: Initial observations on the nervous system of the rat
Findings provide morphological support for the hypothesis that enkephalins are contained in nerve terminals close to opiate receptors as revealed by biochemical techniques. Expand
Opioids modulate periodicity rather than efficacy of peristaltic waves in the guinea pig ileum in vitro.
Enhancement of peristalsis by naloxone decreased over time, although enough n aloxone was present to occupy all opioid receptors, which suggests that opioid receptor blockade induces some compensatory mechanism. Expand
Recent findings in the structure—functional characteristics of bacteriorhodopsin
This study has been made to give a fuller chemical description of bacteriorhodopsin, including its native structure localized within purple membrane and to obtain independent data confirming and elaborating Henderson and Unwin’s model. Expand
Statistical estimation of the minimal detectable concentration ("sensitivity") for radioligand assays.
  • D. Rodbard
  • Mathematics, Medicine
  • Analytical biochemistry
  • 1978
“Pooling” of information about the variability of response at zero dose results in improved utilization of data, with increased degrees of freedom and smaller MDC. Expand