l-365260 and lorglumide

The effects of oxytocin on gastric emptying, gastrointestinal transit, and plasma levels of cholecystokinin (CCK) were studied in ovariectomized rats. Gastrointestinal motility was assessed in rats 15 min after intragastric instillation of a test meal containing charcoal and Na2 51CrO4. Gastric emptying was determined by measuring the amount of radiolabeled chromium contained in the small intestine as a percentage of the initial amount received. Gastrointestinal transit was evaluated by calculating the geometric center of distribution of the radiolabeled marker. Blood samples were collected for CCK radioimmunoassay. After administration of oxytocin (0.2-0.8 mg/kg), gastric emptying and gastrointestinal transit were inhibited, whereas plasma concentration of CCK was increased in a dose-dependent manner. Atosiban, an oxytocin receptor antagonist, effectively attenuated the oxytocin-induced inhibition of gastric emptying and gastrointestinal transit. However, administration of atosiban alone had no effect on gastric emptying and gastrointestinal transit. The selective CCK1 receptor antagonists, devazepide and lorglumide, effectively attenuated the oxytocin-induced inhibition of gastric emptying and gastrointestinal transit. L-365, 260, a selective CCK2 receptor antagonist, did not alter the oxytocin-induced inhibition of gastric emptying and gastrointestinal transit. These results suggest that oxytocin inhibits gastric emptying and gastrointestinal transit in ovariectomized rats via a mechanism involving the stimulation of CCK release and CCK1 receptor activation.

Topics: Animals; Benzodiazepinones; Cholecystokinin; Devazepide; Dose-Response Relationship, Drug; Eating; Female; Gastric Emptying; Gastrointestinal Motility; Gastrointestinal Transit; Ovariectomy; Oxytocin; Phenylurea Compounds; Proglumide; Radioimmunoassay; Rats; Rats, Sprague-Dawley; Receptor, Cholecystokinin A; Receptors, Cholecystokinin; Receptors, Oxytocin; Sincalide; Vasotocin

The effects of oxytocin (OT) on gastric emptying, gastrointestinal transit, and plasma levels of cholecystokinin (CCK) were studied in female rats. Gastrointestinal motility was assessed in rats 15 min after intragastric instillation of a test meal containing charcoal and Na(2)(51)CrO(4). Gastric emptying was determined by measuring the amount of radiolabeled chromium contained in the small intestine as a percentage of the initial amount received. Gastrointestinal transit was evaluated by calculating the geometric center of distribution of the radiolabeled marker. Blood samples were collected for CCK radioimmunoassay. After administration of OT (0.2-0.8 mg/kg), gastric emptying and gastrointestinal transit were inhibited, whereas the plasma concentration of CCK was increased in a dose-dependent manner. Atosiban, an oxytocin receptor antagonist, effectively attenuated the OT- induced inhibition of gastric emptying and gastrointestinal transit. However, administration of atosiban alone had no effect on gastric emptying and gastrointestinal transit. The selective CCK(1) receptor antagonists, devazepide and lorglumide, effectively attenuated the OT-induced inhibition of gastric emptying and gastrointestinal transit. L-365, 260, a selective CCK(2) receptor antagonist, did not alter the OT-induced inhibition of gastric emptying and gastrointestinal transit. These results suggest that OT inhibits gastric emptying and gastrointestinal transit in female rats via a mechanism involving CCK stimulation and CCK(1) receptor activation.

Topics: Animals; Benzodiazepinones; Cholecystokinin; Devazepide; Dose-Response Relationship, Drug; Female; Gastric Emptying; Gastrointestinal Agents; Gastrointestinal Transit; Hormone Antagonists; Oxytocin; Phenylurea Compounds; Proglumide; Rats; Rats, Sprague-Dawley; Receptors, Cholecystokinin; Vasotocin

The effects of estradiol benzoate (EB) on gastric emptying, gastrointestinal transit and plasma levels of cholecystokinin (CCK) were studied in ovariectomized rats.. Gastrointestinal motility was assessed in rats 15 min after intragastric instillation of a test meal containing charcoal and Na2 51CrO4. Gastric emptying was determined by measuring the amount of radiolabeled chromium contained in the small intestine as a percentage of the initial amount received. Gastrointestinal transit was evaluated by calculating the geometric center of distribution of the radiolabeled marker. Blood samples were collected for E2 and CCK radioimmunoassay.. After treatment of EB (4-25 microg/kg), gastric emptying and gastrointestinal transit were inhibited, whereas plasma concentrations of E2 and CCK were increased in a dose-dependent manner. The selective CCK(A) receptor antagonists, devazepide and lorglumide, effectively attenuated the EB-induced inhibition of gastric emptying and gastrointestinal transit. L-365,260, a selective CCK(B) receptor antagonist, did not alter the EB-induced inhibition of gastric emptying and gastrointestinal transit.. The results suggest that EB inhibits gastric emptying and gastrointestinal transit in ovariectomized rats via a mechanism involving CCK stimulation and CCK(A) receptor activation.

Topics: Animals; Benzodiazepinones; Cholecystokinin; Devazepide; Disease Models, Animal; Estradiol; Female; Gastric Emptying; Gastrointestinal Transit; Hormone Antagonists; Ovariectomy; Phenylurea Compounds; Proglumide; Rats; Rats, Sprague-Dawley; Receptors, Cholecystokinin; Time Factors

Cholecystokinin (CCK) can have effects opposite those of opioids. The present study was undertaken to determine whether peripheral injections of antagonists of the CCK1 receptor (lorglumide) and the CCK2 receptor (L-365,260) can influence the effects of morphine on maternal behavior during lactation. A total of 110 female Wistar rats were tested on days 5 and 6 postpartum. Groups were randomly assigned to morphine vehicle (MV-SC) + saline (S-IP), MV + lorglumide (LOR: 1.0 or 10.0 mg/kg), MV + L-365,260 (10 mg/kg), morphine chlorhydrate (MC: 7.0 mg/kg) + S, MC + LOR (1.0 or 10.0 mg/kg), and MC + L-365,260 (1.0 or 10 mg/kg). Maternal behavior testing was started 30 min after the injections, at which time pups were placed in the home cage of their mother. Latencies for retrieval, grouping, and crouching responses were scored. The results show that both lorglumide and L-365,260 potentiated the MC-induced inhibition of maternal behavior. In addition L-365,260 treatment alone inhibited maternal behavior. Blockade of both the CCK1 and CCK2 receptors potentiated the morphine-induced disruption of maternal behavior, while CCK2 antagonism alone also inhibited this behavior. The results suggest that CCK antagonism of opioid-induced disruption of maternal behavior occurs due to the action of CCK on both CCK1 and CCK2 receptor subtypes.

Topics: Animals; Benzodiazepinones; Female; Hormone Antagonists; Lactation; Maternal Behavior; Morphine; Narcotics; Phenylurea Compounds; Proglumide; Rats; Rats, Wistar; Receptor, Cholecystokinin A; Receptor, Cholecystokinin B; Receptors, Cholecystokinin

The role of gastrin in the control of growth of renal G401 cells isolated from a human nephroblastoma (Wilms' tumour) was investigated. G401 cell growth was enhanced in the presence of exogenous gastrin. Addition of anti-gastrin antibodies to serum-free medium significantly inhibited the growth of G401 cells. G401 cells contained the equivalent of 4.3 pg/10(6) cells of gastrin, and serum-free medium collected over 48 hr from G401 cells contained the equivalent of 38 ng/10(6) cells of gastrin, as determined by radioimmunoassay. Growth of G401 cells was inhibited in a concentration-related way by a variety of gastrin/CCK receptor antagonists. Devazepide and proglumide were, respectively, the most and the least potent inhibitors of G401 cell growth (potency order devazepide > L-365,260 = lorglumide > loxiglumide > benzotript > proglumide). These gastrin/CCK receptor antagonists had similar growth-inhibitory activities in human colonic adenocarcinoma HCT-116 cells. Growth of HCT-116 cells was stimulated to a lesser extent, as compared with G401 cells, by exogenous gastrin, and endogenous gastrin was not detectable in HCT-116 cells. The results are consistent with a role for a gastrin-like peptide in the control of growth of a renal cell line. The data suggest that gastrin/CCK receptor antagonists warrant further investigation as therapeutic agents for the control of gastrin-responsive tumours derived from outside, as well as inside, the gastrointestinal tract, including tumours derived from the kidney.

Topics: Benzamides; Benzodiazepinones; Cell Division; Devazepide; Gastrins; Humans; Indoles; Kidney Neoplasms; Meglumine; Phenylurea Compounds; Proglumide; Receptors, Cholecystokinin; Tumor Cells, Cultured; Wilms Tumor

Cholecystokinin (CCK) plays an important role in gallbladder contraction and gut motility. Sincalide (CCK-8) evoked guinea pig isolated ileum contraction at 10(-5)-10(-1) mumol.L-1 in a concentration-dependent manner, EC50 being 207 pmol.L-1. It delayed the gastric emptying as well. The rate of inhibition of gastric emptying was 71 +/- 12% at 100 micrograms.kg-1 by ip. Sincalide antagonists: lorglumide, devazepide, and L-365,260 antagonized the ileal smooth muscle response to sincalide in a concentration-dependent manner. Their pA2 were 7.30, 10.02, and 7.77, respectively. Lorglumide, devazepide, and L-365,260 inhibited the delaying of gastric emptying evoked by sincalide. The IC50 were 0.11, 0.0064, and 0.66 mg.kg-1, respectively.

Topics: Animals; Benzodiazepinones; Devazepide; Gastric Emptying; Gastrointestinal Motility; Guinea Pigs; Ileum; Male; Muscle Contraction; Muscle, Smooth; Phenylurea Compounds; Proglumide; Rats; Rats, Sprague-Dawley; Receptors, Cholecystokinin; Sincalide