Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-4-7
pubmed:abstractText
To investigate the mechanisms responsible for the distinct cutaneous manifestations of erythropoietic protoporphyria and porphyria cutanea tarda, the effects of protoporphyrin (PP) and uroporphyrin (URO), the predominant porphyrins in the respective disease, on mast cells were examined. Release of preformed and generated mediators was assessed by the release of radioactivity from cells labeled with [3H]serotonin and [14C]arachidonic acid, respectively. Clinically relevant doses of PP (25-500 ng/ml) and 396-407 nm irradiation (3-16 X 10(2)J/m2) induced maximal net release of preformed mediators of 44.52 +/- 6.6 to 58.01 +/- 4.0% (mean +/- SE). In contrast, irradiation in the presence of URO (50-5000 ng/ml) resulted in less than 5% net release. [3H]Serotonin release induced by PP and irradiation was calcium-independent, and was not enhanced by phorbol 12-myristate 13-acetate, a known activator of protein kinase C. This release was suppressed by catalase, a scavenger of hydrogen peroxide. Furthermore, irradiation in the presence of PP, but not in the presence of URO, resulted in perturbation of cell membrane. Irradiation in the presence of PP also resulted in a maximal net release of generated mediators of 9.98 +/- 3.5% (mean +/- SE), whereas similar treatment in the presence of URO induced less than 0.5% net release. These results suggested that the burning, stinging, erythema, and edema experienced by patients with erythropoietic protoporphyria following sun exposure, and the lack of such findings in patients with porphyria cutanea tarda, may be explained, at least in part, by the differential effects of PP and URO on mast cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-202X
pubmed:author
pubmed:issnType
Print
pubmed:volume
88
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
281-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Differential effects of protoporphyrin and uroporphyrin on murine mast cells.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.