A MICRO-RADIOIMMUNOASSAY FOR THE MEASUREMENT OF INTRACELLULAR CAMP

We have developed a rapid and sensitive micro-radioimmunoassay for the detection of cellular cAMP. The assay employs a simple method for pre paring cellular lysates that requires as few as 500 cells per data poi nt. Cellular lysates are incubated with cAMP-specific antibody complex es and [I-125]cAMP in 96-well plates, harvested onto glass fiber filte rs and analyzed using a commercial autoradiograph imaging system. This method provides significant savings in reagents and may be particular ly useful in situations where only a limited number of cells are avail able.