Linked Life Data

203595

Source:http://linkedlifedata.com/resource/pubmed/id/203595

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1978-4-26
pubmed:abstractText
Crude receptor preparations of rabbit mammary gland were made by differential centrifugation and reacted with lactoperoxidase-iodinated ovine prolactin (oPRL) in order to determine their binding characteristics. Receptors prepared from the mammary glands of animals less than 4 days postpartum bound oPRL with high affinity (Ka = 3.50 X 10(9) M-1), in good agreement with previous results of other investigators. The binding capacity of these preparations was 107 +/- 16.3 fmol/mg of protein. In contrast, receptors prepared from the mammary glands of late lactating rabbits (Days 25 to 30 of lactation) showed a 2.5-fold increase in binding affinity (Ka = 8.63 X 10(9) M-1, p less than 0.001) without a significant increase in binding capacity (135 +/- 21.4 fmol/mg, p greater than 0.2). Kinetic experiments revealed that the rates of association of hormone and receptor were identical in early and late receptor preparations, and that the 2.5-fold decrease the dissociation rate observed in the late preparations was fully explanatory of the differences in equilibrium binding. The mechanism of this affinity increase is not known. Such a change in binding characteristics, which would tend to enhance tissue responsiveness, may underlie the well characterized maintenance of full lactation in women despite falling concentrations of prolactin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
253
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1560-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1978
pubmed:articleTitle
Rabbit mammary prolactin receptors. Demonstration of a late puerperal increase in affinity.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.