Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5A
pubmed:dateCreated
1983-3-11
pubmed:abstractText
A highly sensitive and specific radioimmunoassay for LRF was applied to the measurement of endogenous LRF in various hypothalamic extracts. Specific antiserum was obtained by injecting LRF conjugated to human serum albumin with glutaraldehyde. Thyrotropin-releasing hormone, lysine vasopressin, oxytocin, noradrenaline, LH, FSH and cortical extracts did not appear to affect the assay, and the maximum cross-reaction observed with the LRF analogs tested was 8.5 p. 100 with LRF 2-10. The best detection limit (0.4 pg/tube) was usually obtained when the labelled LRF had been purified by polyacrylamide gel electrophoresis. Within and between-assay coefficients of variation were 8.0 and 12.6 p. 100, respectively (from B/Bo = 20 to 80 p. 100). Synthetic LRF administered to rams by intravenous injection was readily detectable in the peripheral plasma. However, the direct measurement of plasma endogenous LRF may give misleading results due to non-specific interference by plasma factors. No endogenous LRF could be detected in plasma methanol or acetone extracts obtained from rats and rams in various physiological conditions. The inhibition curves parallel to the synthetic LRF curve were obtained by diluting the crude hypothalamic extracts of rams and rats, and a good correlation (r = 0.997) with the Ramirez-McCann bioassay resulted, indicating that using radioimmunoassay to determine hypothalamic LRF content may be fruitful in studying hypothalamo-pituitary gonad interactions. The LRF content of rat and ovine hypothalami ranged from 2-8 to 20-80 ng of LRF, respectively.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0181-1916
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1489-501
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Reassessment of LRF radioimmunoassay in the plasma and hypothalamic extracts of rats and rams.
pubmed:publicationType
Journal Article, Comparative Study