Cyclo (His-Pro), a metabolite of thyrotropin-releasing hormone: specific binding to rat liver membranes.
[3H]cyclo(His-Pro) bound with high affinity (59 nM) to a single class of sites in rat liver plasma membranes, without significant tracer degradation during equilibration for 60 min at 0 degrees C. Binding was specific and saturable (3.9 pmol/mg protein), and were increased by the addition of K+, Mg++ and Na+ at optimal concentrations, but not of Ca++ at all concentrations tested. In vivo administration of cyclo(His-Pro), but not thyrotropin-releasing hormone, to rats caused the downregulation of cyclo(His-Pro)-binding sites with decreases in specific binding numbers but did not change binding affinity.
Mori
M
M
Yamada
M
M
Yamaguchi
M
M
Suzuki
M
M
Ohshima
K
K
Kobayashi
I
I
Kobayashi
S
S
D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D003080:Cold Temperature; D008099:Liver / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism; D008297:Male; D008566:Membranes / Q000378:metabolism; D010456:Peptides, Cyclic / Q000378:metabolism*; D010879:Piperazines / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone / Q000378:metabolism*; D013997:Time Factors
D010456:Peptides, Cyclic; D010879:Piperazines; D013973:Thyrotropin-Releasing Hormone; D012964:Sodium; D008274:Magnesium; C015924:histidyl-proline diketopiperazine; D011188:Potassium; D002118:Calcium