Linked Life Data

303698

Source:http://linkedlifedata.com/resource/pubmed/id/303698

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1978-1-27
pubmed:abstractText
1. Bleaching/regeneration cycles were performed in perfused frog retina while the optical transmittance at suitable wave-lengths was measured continously. Rhodopsin was identified from its spectral absorbance, its photosensitivity and from the kinetics of its regeneration. 2. In the absence of the pigment epithelium regeneration was complete when not more than 2-5% of the rhodopsin initially present had been bleached. However, the cycles could be repeated to a total of regenerated rhodopsin exceeding that explicable on the utilization of stored chromophores. The rate of regeneration was fast, with 0-12 min-1 rate constant, following first order reaction kinetics. Under these conditions the cycle does not seem to involve stages beyond metarhodopsin II. With the moderate bleaching intensities used, half-time 53 min, the Bunsen-Roscoe law was obeyed up to 15 min, indicating a capacity for the photoproducts to be accomondated in situ for subsequent regeneration. 3. It is concluded that only substantial bleaches, which exceed that capacity, result in hydrolysed chromophores. These surplus chromophores become esterified and are temporarily taken up by the pigment epithelium to be re-entered into the visual cycle as fast as they can be processed by the regenerative machinery of the rod outer segments.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-3751
pubmed:author
pubmed:issnType
Print
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
747-59
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1977
pubmed:articleTitle
Regeneration of rhodopsin in frog rod outer segments.
pubmed:publicationType
Journal Article, In Vitro