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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1990-5-21
|
| pubmed:abstractText |
In the present study characterization of phosphatidylinositol 4,5-bisphosphate-specific phospholipase C (PIP2-PLC) activity and receptor-mediated hydrolysis of PIP2 in rat anterior pituitary membranes were investigated. Incubation of the membrane fraction of anterior pituitary homogenate with [3H]inositol-labeled PIP2 in the presence of calcium increased the concentration of the water-soluble degradation product inositol trisphosphate (IP3) in a time-dependent manner. PIP2-PLC in the rat anterior pituitary had a pH optimum at 5.5 and a requirement for cations. Ca2+ and Mg2+ could activate the enzyme. Activity was maximal at a total magnesium concentration of 1 mM and at a free Ca2+ concentration of 100 microM. The addition of the detergent Triton X-100 (0.05% w/v) to the membrane fraction resulted in a 50% decrease of PIP2-PLC activity, whereas the presence of sodium deoxycholate (1 mg/ml) in the membrane fraction increased the PIP2-PLC activity by 100%. The tachykinins substance P, 8-Tyr-substance P, physalaemin, neurokinin A, eledoisin, kassinin and neurokinin B induced receptor-mediated breakdown of [3H]inositol-labeled PIP2 in the membrane fraction in a concentration-dependent manner, but with different potencies. The tachykinins displayed the following rank order of potencies: substance P greater than 8-Tyr-substance P greater than physalaemin greater than neurokinin A greater than eledoisin greater than kassinin greater than neurokinin B, which is consistent with the involvement of a NK-1 receptor. Combined treatment of anterior pituitary membranes by substance P and thyrotropin-releasing hormone (TRH) resulted in an additional increase in PIP2-PLC activity compared to stimulation with TRH alone.
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Detergents,
http://linkedlifedata.com/resource/pubmed/chemical/Magnesium,
http://linkedlifedata.com/resource/pubmed/chemical/Octoxynol,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositol 4,5-Diphosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositols,
http://linkedlifedata.com/resource/pubmed/chemical/Polyethylene Glycols,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Neurokinin-1,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Neurotransmitter,
http://linkedlifedata.com/resource/pubmed/chemical/Substance P,
http://linkedlifedata.com/resource/pubmed/chemical/Tachykinins,
http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Feb
|
| pubmed:issn |
0303-7207
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| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
12
|
| pubmed:volume |
69
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
69-78
|
| pubmed:dateRevised |
2007-11-15
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| pubmed:meshHeading |
pubmed-meshheading:1691115-Animals,
pubmed-meshheading:1691115-Calcium,
pubmed-meshheading:1691115-Cell Membrane,
pubmed-meshheading:1691115-Chromatography, High Pressure Liquid,
pubmed-meshheading:1691115-Detergents,
pubmed-meshheading:1691115-Hydrogen-Ion Concentration,
pubmed-meshheading:1691115-Hydrolysis,
pubmed-meshheading:1691115-Magnesium,
pubmed-meshheading:1691115-Male,
pubmed-meshheading:1691115-Octoxynol,
pubmed-meshheading:1691115-Phosphatidylinositol 4,5-Diphosphate,
pubmed-meshheading:1691115-Phosphatidylinositols,
pubmed-meshheading:1691115-Pituitary Gland, Anterior,
pubmed-meshheading:1691115-Polyethylene Glycols,
pubmed-meshheading:1691115-Rats,
pubmed-meshheading:1691115-Rats, Inbred Strains,
pubmed-meshheading:1691115-Receptors, Neurokinin-1,
pubmed-meshheading:1691115-Receptors, Neurotransmitter,
pubmed-meshheading:1691115-Substance P,
pubmed-meshheading:1691115-Tachykinins,
pubmed-meshheading:1691115-Type C Phospholipases
|
| pubmed:year |
1990
|
| pubmed:articleTitle |
Substance P and related tachykinins induce receptor-mediated hydrolysis of polyphosphoinositides in the rat anterior pituitary.
|
| pubmed:affiliation |
Protein Laboratory, University of Copenhagen, Denmark.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|