Somatostatin radioreceptor assay: development and application to the measurement of somatostatinlike activity in the rat central nervous system.
Functional receptors for the neuropeptide somatostatin have previously been characterized in a clonal line (GH4C1) of rat pituitary tumour cells. We have utilized GH4C1 cell receptors to develop a radioreceptor assay for the measurement of somatostatinlike activity in biological samples. The concentration of somatostatinlike activity was determined in various regions of the rat central nervous system by both radioreceptor assay and two radioimmunoassays. For all tissue samples tested, less somatostatinlike activity was measured by radioreceptor assay than by radioimmunoassay. Furthermore, the ratio of the measured activity in the two assays varied from 0.31 to 0.76. It is likely that these differences are at least partially due to the different affinities of GH4C1 cell receptors and the two antibodies for somatostatin-14 and somatostatin-28 which are both present in the rat central nervous system.
D000818:Animals; D002490:Central Nervous System / Q000032:analysis*; D008297:Male; D010455:Peptides / Q000032:analysis*; D011863:Radioimmunoassay; D011869:Radioligand Assay / Q000379:methods; D051381:Rats; D011956:Receptors, Cell Surface / Q000032:analysis*; D017481:Receptors, Somatostatin; D013004:Somatostatin / Q000031:analogs & derivatives / Q000378:metabolism; D014018:Tissue Distribution
D010455:Peptides; D011956:Receptors, Cell Surface; D017481:Receptors, Somatostatin; C029993:somatostatin-like peptides; D013004:Somatostatin; C032367:somatostatin, Tyr(11)-