J E McGuigan

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The effects of alterations in availability and access of extracellular media calcium on antral gastrin release were examined in the basal state and in response to cholinergic stimulation in rat antral organ culture experiments. In the presence of either divalent cationic chelator (EGTA) or calcium channel blocker (verapamil, nifedipine),(More)
Anorexia nervosa (AN) is a syndrome of unknown cause characterized by voluntary starvation. Cholecystokinin has been implicated as a neuroendocrine regulatory factor in control of satiety. Relatively little information is known about gastrointestinal hormone responses to feeding in subjects with anorexia nervosa. In the present studies, we examine fasting(More)
The present studies were directed to examine the effects of beta-adrenergic and cholinergic stimulation on gastrin release and to assess the potential role of gastrin-releasing peptide in exerting these effects, utilizing incubated rat antral mucosa. Rat antral mucosa was incubated at 37 degrees C in Krebs-Henseleit bicarbonate buffer, pH 7.4, continuously(More)
The present studies were directed to examine and quantify binding and degradation of radiolabelled cholecystokinin (CCK) peptides by isolated rat liver cells. After incubation with liver cells (4.5 x 10(6) cells/ml) at 14 degrees C, minimal binding (less than 5%) of labelled CCK33 was detected. When labelled nonsulfated (nsCCK8) and sulfated CCK8 (sCCK8)(More)
Rat antral mucosal fragments were maintained in short-term culture to examine the relative potencies and receptor specificity of the cholinergic agonist, carbachol, and adrenergic agents, norepinephrine, isoproterenol, clonidine and phenylephrine in stimulating gastrin release. Results of these studies indicate that norepinephrine and carbachol evoke(More)
Vasoactive intestinal peptide (VIP) concentrations were measured by radioimmunoassay in plasma from portal and peripheral venous blood obtained from six alert, non-anesthetized dogs before and after gastric infusion of a 10% peptone meal. Mean basal portal and cephalic vein plasma VIP concentrations were 42 +/- 11.7 and 42 +/- 8.0 (S.E.M.) pg/ml,(More)
The effects of the microtubule stabilizing agent, deuterium oxide, on in vitro rat antral gastrin release were examined under basal conditions and during stimulation with isobutyl methylxanthine and bombesin plus isobutyl methylxanthine. Basal gastrin release from antral mucosal fragments was unaffected by increasing media concentration of deuterium oxide(More)
Glucagon given as an intravenous injection of 2 mg (0.57 mmol) or as constant intravenous infusion of 1.64 microgram/kg/h (0.47 nmol/kg/h) significantly increased gastric mucosal potential difference (PD) in man. Pentagastrin infusion of 2 microgram/kg/h (2.8 nmol/kg/h) dramatically reduced gastric PD in man. The effect of each of these hormones on PD was(More)
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