A rapid method for the measurement of prostaglandin receptors.
A method is presented which provides for a simple and rapid determination of prostaglandin receptors in large numbers of tissue samples. Binding of prostaglandin F2 alpha, to preparations of microsomal membranes obtained from the ovaries of PMSG/hCG-treated rats served as the model system for this study. After incubating the membranes with [3H]-PGF2 alpha +/- graded concentrations of PGF2 alpha for 90 min at 22 degrees C, dextran-coated charcoal was added to adsorb the free PGF2 alpha during a 10 minute period. Centrifugation of the mixture for 3 minutes atop a 2.2M sucrose cushion resulted in the charcoal pelleting to the bottom while the [3H]PGF2 alpha-membrane complex remained at the interface. There was no further significant diffusion of PGF2 alpha after centrifugation, enabling large numbers of samples to be handled within a short period of time. The binding data revealed both high and low affinity receptors: Kd = 5.8 nM and 77 nM with binding capacities of 360 and 4000 fmole/mg protein. Both PGE1 and PGF1 alpha partially displaced [3H]PGF2 alpha from the binding sites whereas PGA2 was without effect. Binding equilibrium was reached within 90--140 min. The results are compatible with those of investigators using other techniques.
D000818:Animals; D015237:Dinoprost; D005260:Female; D008722:Methods; D008861:Microsomes / Q000032:analysis; D010053:Ovary / Q000032:analysis; D011460:Prostaglandins F / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000032:analysis*; D011982:Receptors, Prostaglandin / Q000032:analysis*; D013997:Time Factors
D011460:Prostaglandins F; D011956:Receptors, Cell Surface; D011982:Receptors, Prostaglandin; D015237:Dinoprost