TY - JOUR T1 - The Role of Adenosine Cyclic 3',5'-Monophosphate in Reserpine-Initiated Adrenal Medullary Tyrosine Hydroxylase Induction JF - Molecular Pharmacology JO - Mol Pharmacol SP - 855 LP - 860 VL - 10 IS - 5 AU - R. A. MUELLER AU - U. OTTEN AU - H. THOENEN Y1 - 1974/09/01 UR - http://molpharm.aspetjournals.org/content/10/5/855.abstract N2 - An intact splanchnic nerve is required for the initiation of trans-synaptic induction of tyrosine hydroxylase in rat adrenal medulla. Severing of the splanchnic nerve fibers supplying the left adrenal 4 hr after reserpine administration completely abolished the induction of tyrosine hydroxylase observed 48 hr later on the intact side. Transection of the splanchnic nerves 8 hr after drug administration partially prevented tyrosine hydroxylase induction, whereas transection after 12 hr had no effect on induction. Adrenal medullary cyclic AMP contents were measured at various times up to 12 hr after reserpine. The rapid initial increase in cyclic AMP returned to normal by 90 min and remained there for the next 12 hr. When cyclic AMP had returned to control levels after reserpine, administration of aminophylline (theophylline ethylenediamine) produced a slower rate of increase in cyclic AMP than observed in controls. Therefore it appears either that cyclic AMP is not involved in the trans-synaptic induction of tyrosine hydroxylase observed after reserpine or that the intact splanchnic nerve is required for some part of the inductive process after the cyclic AMP response has terminated. ACKNOWLEDGMENT We wish to thank Miss Petra Tengzelius for her excellent technical assistance. ER -