| Abstract: | The results presented in this study indicate that the defect in catecholamine-stimulated adenylate-cyclase which is characteristic of the ob/ob mouse is associated with a decrease in the sensitivity of the system to guanine nucleotides (guanosine 5'-beta gamma-imido]triphosphate and guanosine 5'-triphosphate). No difference in the beta-adrenergic receptor activity was found between the lean and obese mice on the basis of their capacity to bind the beta-adrenergic antagonist 3H]dihydroalprenolol. The data suggest that a defect in the activation of the adenylate cyclase by beta-adrenergic agents may reside in the guanyl nucleotide binding site(s). |
