Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Metoclopramide has a dual effect on intestinal smooth muscle. Low concentrations of metoclopramide cause potentiation of the responses to substance P, acetylcholine, histamine and barium chloride on the guinea-pig ileum. Higher concentrations produce a depression of smooth muscle responses which is characteristic of the tertiary amine local anesthetics. Neural pathways are involved in the mechanism of potentiation, since the enhancement of the responses to the agonists is abolished by tetrodotoxin. Atropine partially antagonizes the potentiating effect of metoclopramide implying that activation of muscarinic receptors is a contributing factor, but this does not fully explain the potentiation.
 ...
PMID:The effects of metoclopramide in modifying the response of isolated guinea-pig ileum to various agonists. 0 87

A case report and review of the problem of duodenal leiomyoma are presented. Although these lesions are rare and usually asymptomatic, they can present with symptoms of hemorrhage, obstruction, pain, and perforation. Barium roentgenographic examination may show filling defects of compressive lesions. Angiography shows a hypervascular, encapsulated lesion. Endoscopy may reveal a submucosal mass with central depression. At operation, it is important to distinguish the benign leiomyoma from leiomyosarcoma.
 ...
PMID:Duodenal leiomyoma as a cause of gastrointestinal hemorrhage. 30 63

A comparative study was made of macroscopic and radiologic findings about 95 lesions (83 cases) of small cancers (10 mm and below) in the antrum of the stomach, and the following results were obtained. 1) Preoperative diagnostic rate was 11/66 (17%) for lesions of micro-gastric cancers (5 mm and below), and 21/29 (72%) for lesions of small gastric cancers 5.1-10). Lesions of microgastric cancers which were preoperatively diagnosed as such were those with size of 3 to 5 mm accompanied by marginal elevations. 2) Radiologic findings about micro-gastric cancers. Some of the micro-gastric cancers which gave some findings in barium filled pictures existing along the greater or lesser curvature were observed as pictures of slight depression. In the compression pictures were noticed niches of irregular linear or stellar shapes with surrounding translucency. For qualitative diagnosis, the compression method was found most effective. It is considered very important to look for small niches, slight translucency, and slight deformity in the greater or lesser curvature carefully.
 ...
PMID:[A comparative study between radiologic and macroscopic findings of small cancers less than 1 cm in the antrum of the stomach (author's transl)]. 54 12

Biochemical studies showing that lead (Pb++) inhibits cerebellar adenylate cyclase (IC50 = 2 micrometer) prompted us to test the effects of this cation on the depression of spontaneous discharge of Purkinje (P) cells produced by iontophoresis of norepinephrine (NE). Previous studies have suggested that the effects of NE on P cell discharge may be mediated by activation of a NE-sensitive adenylate cyclase. Iontophoresis of Pb++ in situ, and in cerebellar transplants in oculo, reliably antagonized NE responses in over 80% of the P cells studied in both preparations. Blockade was readily seen at iontophoretic currents of 5 to 10 nA. Superfusion of PB++ (5--10 micrometer) into the anterior eye chamber also antagonized NE responses in P neurons of the transplant. Spontaneous discharge rate was either unaffected or slightly elevated at Pb++ levels that almost completely blocked NE. Barium, a heavy metal which does not inhibit adenylate cyclase in vitro, did not block NE effects. Stimulation of parallel fibers or iontophoresis of acetylcholine excited P cells. No antagonism was seen, however, between Pb++ and these acetylcholine or parallel fiber excitations. These results raise the possibility that blockade of brain catecholamine receptors may partially underlie the central nervous system toxicity seen with lead administration.
 ...
PMID:Lead blockade of norepinephrine-induced inhibition of cerebellar Purkinje neurons. 68 19

This study describes the effect of hypertonic solutions on isolated muscle fibers of Callinectes danae. Solutions of twice normal tonicity (2.0 T) inhibit both the normal graded membrane responses and the spikes induced by procaine, tetraethylammonium, or barium. The inhibition is maintained throughout exposure to hypertonic solutions prepared by addition of impermeant solutes such as NaCl, sucrose, or Tris-propionate, but is reversible on their withdrawal. In the presence of permeant solutes such as glycerol or acetamide, the inhibition is transient. In both cases the onset of inhibition of the depolarizing Ca electrogenesis is correlated with shrinkage of the fiber. In the case of permeant solutes, the time course of recovery of the graded responses or the spikes follows the recovery of the fiber volume. Changes in the passive electrical characteristics of the fibers due to hypertonic solutions were unrelated to the blockade of membrane Ca activation. The current-voltage relationship in hypertonic sollution revealed no increase in depolarizing K activation. Inhibition of the graded membrane responses and spikes appears to be associated with depression of Ca conductance. Hypertonic solutions might affect the activation of Ca conductance through reduction of the electric field generated by fixed negative surface charges and/or morphological changes in the T tubules. Membrane depolarization elicited little or no tension in 2.0 T solutions while caffeine contracture (10 mM) with an ampliture of 76% of the maximal contractile ability could still be elicited. This indicates that direct effects of hypertonic solutions on the contractile apparatus were not responsible for loss of tension. The latter is attributed to the inhibition of the transmembrane Ca currents.
 ...
PMID:Inhibition by hypertonic solutions of Ca-dependent electrogenesis in single crab muscle fibers. 91 72

The effect of various local anesthetics and other substances known to modify calcium fluxes in cells, on submaximal responses of guinea-pig ileum to substance P, acetylcholine, histamine and barium chloride was determined. Procaine caused a dose-related depression of the response to all the agonists but the response to substance P was far less susceptible to this depression. Lidocaine, bupivacaine, pramoxine and W 6211 also caused a lower degree of attenuation of the response to substance P than the responses to acetylcholine, histamine and barium chloride. Verapamil caused a dose-related depression of responses to all the agonists equally. The use of calcium-free solutions abolished responses to substance P, acetylcholine and histamine. The response to barium chloride was less affected by calcium withdrawal but was reduced markedly. In the presence of 10 mM lanthanum chloride, the response to all the agonists was abolished. The relative resistance of the substance P responses to antagonism by local anesthetics suggests that different and more efficient channels for calcium entry into the smooth muscle cell are involved.
 ...
PMID:Interactions between local anesthetics and spasmogens on the guinea-pig ileum. 93 95

The incidence of significant arrhythmias and ST segment changes during barium enema examination (BE) was evaluated by Holter monitoring of 58 unselected patients over the age of 60 years. Forty percent of the group developed new significant arrhythmias of which the most common were frequent and/or multifocal premature ventricular contractions. Seven percent demonstrated ST segment depression. Administration of glucagon did not diminish the incidence of arrhythmias. Predictive factors for ECG abnormalities were advancing age, abnormal pre-BE-ECG, and pre-BE orthostatic hypotension. Analysis of arhythmias and response to phywiologic tension. Analysis of arrhythmias and response to physiologic manoeuvres suggested that the abnormalities were related to increased sympathetic tone which may be intensified by hypovolaemia resulting from routine bowel preparation.
 ...
PMID:Predictive factors and mechanism of arrhythmias and myocardial ischaemic changes in elderly patients during barium enema. 100 Jan 70

We describe a radiographic sign of infantile hypertrophic pyloric stenosis. This sign, elicited during firm compression of the barium-coated pyloric region, is a round or avoid filling defect caused by the hypertrophied pyloric muscle protruding en face into the gastric lumen. This filling defect typically reveals a barium-containing central depression or stellate indentation, representing the proximal end of the obstructed pyloric channel. This sign, like the closely related "shoulder sign", appears to establish the diagnosis of hypertrophic pyloric stenosis without need for filling of the pyloric channel or for additional radiographic maneuvers.
 ...
PMID:The olive on end: a useful variant of the "shoulder" sign in the barium X-ray diagnosis of idiopathic hypertrophic pyloric stenosis. 152 50

The effects of the alkali metal ions cesium (Cs+) and rubidium (Rb+) and alkaline earth metal ions barium (Ba2+) and strontium (Sr2+) on ganglionic transmission in various calcium (Ca2+) concentrations were investigated in rat isolated superior cervical ganglia. Cesium (1 and 2 mM) moderately supported transmission in low Ca2+ and potentiated the compound action potential (CAP) at high Ca2+ concentration. Higher concentrations of Cs+ caused depression of CAP especially at lower Ca2+ concentration. Cesium (1-4 mM) induced large spontaneous rhythmic spikes or burst of spikes. At 4 mM, Rb+ potentiated CAP at all Ca2+ concentrations. As with Cs+, higher concentrations of Rb+ inhibited CAP except at large Ca2+ concentrations. Barium (1-6 mM) effectively enhanced transmission at all Ca2+ concentrations. Strontium enhanced transmission only at very low Ca2+ concentrations. No enhancement was seen with Sr2+ in the presence of normal or higher Ca2+. The results indicate that Cs+ and Rb+ may antagonize Ca2+ effects at release sites while allowing more Ca2+ influx into the nerve terminal as a result of K+ channel blockade. Barium and to a lesser extent Sr2+ may substitute for Ca2+ in the process of transmitter release in the superior cervical ganglia of rats.
 ...
PMID:Effects of inorganic potassium channel blockers on calcium requirement of transmission in a sympathetic ganglion. 165 60

During the development of large bowel cancer alterations in colonic epithelial ion transport have been observed some of which result in altered intracellular ionic composition. In many tumors intracellular sodium and potassium become elevated and depressed, respectively. This observation suggests that mechanisms governing intracellular homeostasis for sodium and potassium are no longer tightly regulated. Changes in cell membrane permeability, sodium, potassium-ATPase K(+)-ATPase) pump activity, or both may be responsible for these alterations. It is not known when during initiation and development of cancer such changes may occur. To assess whether there are changes in the Na+, K(+)-ATPase pump early during the induction of large bowel cancer and prior to any notable histological changes, we measured the kinetics of the Na+, K(+)-pump in distal colonic mucosa of CF1 mice one week following only four weekly injections of the carcinogen 1,2-dimethyhydrazine (DMH). The kinetics of the pump were found to be best described by a model of highly cooperative binding. The VMAX of the pump in premalignant mucosa was lower for both sodium and potassium substrate activation (55-65% of control) with little change in other kinetic parameters. Depression of VMAX could not be attributed to an increased barium blockable potassium conductance of the basolateral membrane. Na+,K(+)-ATPase activity was also decreased by 50% in the distal colon of DMH treated mice, but was not affected in the less cancer susceptible proximal colon. These data demonstrate that alterations occur in the Na+,K(+)-pump in premalignant mucosa months before gross tumors develop, and these changes may partially explain the altered levels of Na+ and K+ in the cytoplasm of pre-malignant and malignant colonocytes.
 ...
PMID:Inhibition of the Na+,K(+)-ATPase pump during induction of experimental colon cancer. 166 99


1 2 3 4 5 6 7 8 Next >>