Magnesium-dependent non-specific binding of [125I]prolactin to myelinated tracts in the rat central nervous system.
An in vitro autoradiographic assay was used in identifying a magnesium-dependent, non-specific binding of [125I] prolactin to myelinated fiber tracts in the rat brain. Frozen tissue sections were incubated for 18 h at 4 degrees C in media which included [125I]prolactin alone or with a 500 fold excess of unlabelled prolactin. Magnesium in the incubation medium caused a non-specific binding of radiolabelled prolactin to the myelinated fiber tracts in the brain. In contrast, calcium did not facilitate prolactin non-specific binding to myelin. Hence, calcium should optimize the detection of specific prolactin binding sites in the brain by in vitro autoradiographic or radioreceptor assays.
Mangurian
L P
LP
Department of Anatomy, George Washington University Medical Center, Washington, D.C.
Walsh
R J
RJ
Posner
B I
BI
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology; D002831:Choroid Plexus / Q000378:metabolism; D007457:Iodine Radioisotopes; D008274:Magnesium / Q000494:pharmacology*; D009186:Myelin Sheath / Q000378:metabolism*; D011388:Prolactin / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011981:Receptors, Prolactin / Q000378:metabolism
D007457:Iodine Radioisotopes; D011981:Receptors, Prolactin; D011388:Prolactin; D008274:Magnesium; D002118:Calcium