A method is described which allows measurement of cyclic AMP and cyclic GMP in histologically defined tissue samples containing as little as 0.6 fmol of either compound. This permits, for example, assays of freeze-dried samples as small as 0.03 μg dry weight from individual retina layers or 4-μg samples from individual layers of cerebellum. The procedure involves a modified radioimmunoassay at reduced volume for acetylated cyclic nucleotides in combination with some of the techniques previously developed for quantitative histochemical assays.
Bibliographical noteFunding Information:
by USPHS Grants NS-09667, NS-13104, NS-08862, NS-05613, Cancer Society Grant BC-4Q. should be addressed.