β-Adrenoceptor and post-receptor components show different rates of desensitization to desipramine

Serotonin (5‐ht) Receptor, 5‐ht Transporter and G Protein‐effector Expression: Implications for Depression

“…Nevertheless, several interesting, novel common effects have emerged from our studies ( Table 1). All ADS tended to decrease the immunolabeling of Gas in the hippocampus, consistent with the recent report of post-receptor desensitization of hippocampal adenylyl cyclase activity following chronic DMI (Tionga and Richardson, 1990), and suggesting a coordinate downregulation of the p-adrenoceptor-Gs-adenylyl cyclase complex by ADS. In view of the well known hypercortisolemia and activation of the HPA axis observed in a subset of depressed patients, and the observation that chronic stress may play a role in the development of depression, it is noteworthy that the effects of ADS on Gas are the opposite of those observed with chronic glucocorticoid administration (Saito et al, 1989;Lesch and Lerer, 1991).…”

Signal-transducing G proteins and antidepressant Drugs: Evidence for modulation of α subunit gene expression in rat brain

“…Nevertheless, several interesting, novel common effects have emerged from our studies. All ADs tended to decrease the immunolabeling of Gas in the hippocampus, consistent with the recent report of post-receptor desensitization of hippocampal adenylyl cyclase activity following chronic DMI (Tiong and Richardson 1990), and suggesting a coordinate downregulation of the 13-adrenoceptor-Gs-adenylyl cyclase complex by ADs (Sugrue 1983;Suiser 1984). In view of the well known hypercortisolemia and activation of the HPA axis observed in a subset of depressed patients (Nemeroff 1987), and the observation that chronic stress may play a role in the development of depression, it is noteworthy that the effects of ADs on Got+ are the opposite of those observed with chronic glucocorticoid administration (Saito et ai 1989;Lesch and Lerer 1991).…”

“…The reason(s) for the failure to detect an alteration in the immunolabeling of Got~ or Goti following ADs in vitro, despite the functional evidence for attenuation of Gs function, is presently unclear. It is possible that the decrease in G% and Gotw2 concentrations in vivo require an intact integrated system (or at least presynaptic input); however, more recent in vivo studies have also demonstrated that ADs result in an early "uncoupling" of the 13-receptor from Gs, followed by changes in G~ function after chronic (> 3 wk) treatment (Okada et al 1986;Tiong and Richardson 1990). Thus, it remains possible that our failure to detect any alterations in the immunolabeling of Got, or GoL~ following in vitro incubation of C6 cells with either DMI or IDZ was due simply to the relatively short (5 day) incubation period.…”

Changes in postnatal norepinephrine alter alpha-2 adrenergic receptor development

“…This has been documented for beta-adrenergic receptors (Daws et al, 1998; Tiong and Richardson, 1990) and for A2AR using either antagonists or agonists to label the receptor (Barturen and Garcia-Sevilla, 1992; Deupree et al, 2007; Subhash et al, 2003). The response of the mature brain to alterations in NE level is the opposite of changes found in developing brain.…”