Photoaffinity labelling of the oxytocin receptor in plasma membranes from rat mammary gland.
Plasma membranes from rat mammary gland containing a high concentration of [3H]oxytocin binding sites (2.8 pmol/mg protein) were used for photoaffinity labelling experiments. Competitive binding experiments show that these receptors bind with high affinity the specific oxytocin agonist [Thr4, Sar7]oxytocin and the analogue of 1-deamino-[8-lysine]vasopressin containing a photoreactive azidobenzoyl group (Abz) at the side chain of lysine. The tritium-labelled (50 Ci/mol) photoreactive analogue incorporated into a membrane protein with an apparent relative molecular mass of 65,000 +/- 3000 Da (n = 16). The labelling of this protein was completely suppressed by an excess of oxytocin.
Müller
M
M
Max-Planck-Institut für Biophysik, Frankfurt, FRG.
Soloff
M S
MS
Fahrenholz
F
F
D000345:Affinity Labels; D000818:Animals; D001667:Binding, Competitive; D004591:Electrophoresis, Polyacrylamide Gel; D066298:In Vitro Techniques; D008321:Mammary Glands, Animal / Q000032:analysis / Q000378:metabolism*; D008970:Molecular Weight; D010121:Oxytocin / Q000032:analysis / Q000378:metabolism*; D010777:Photochemistry; D051381:Rats; D011945:Receptors, Angiotensin / Q000032:analysis / Q000378:metabolism*; D018045:Receptors, Oxytocin; D013329:Structure-Activity Relationship
D000345:Affinity Labels; D011945:Receptors, Angiotensin; D018045:Receptors, Oxytocin; D010121:Oxytocin