RESUMO
OBJECTIVE: This study is to explore the effects on specific bindings between [ 3H]RX821002, alpha-2 adrenergic receptor antagonist and alpha-2 adrenergic receptor in rat brain by G-protein modulation. METHODS: The radioligand binding receptor study was conducted with [ 3H]RX821002, a new alpha-2 adrenergic receptor antagonist, in the presence or absence of Gpp(NH)p and pertussis toxin. RESULTS: The alpha-2 adrenergic receptors were saturated with [ 3H]RX821002 in the fashion of the single binding site. The dissociation constant (Kd) was 0.70+/-0.30 nM, and maximum binding (Bmax) was 599.9+/-283.4 fmol/mg protein. The saturation study showed that the maximum binding (B max ; 668.0+/-50.1 fmol/mg protein) was increased and the dissociation constant (Kd ; 0.61+/-0.14 nM) was decreased significantly in the presence of Gpp (NH)p compared to those (B max ; 559.8+/-81.9 fmol/mg protein, Kd ; 0.87+/-0.14 nM) in the absence of Gpp (NH)p (by paired t-test ; B max, p=0.023, Kd, p=0.005). In the presence of pertussis toxin, the maximum binding (B max ; 617.0+/-58.5 fmol/mg protein) was increased significantly (by paired t-test ; B max, p=0.001) but the issociation constant (Kd ; 0.92+/-0.24 nM) was not decreased compared to those (B max ; 554.1+/-66.1 fmol/mg protein, Kd ; 0.89+/-0.24 nM) in the absence of pertussis toxin. CONCLUSION: These results confirm that the binding profiles between [ 3H]RX821002 and alpha-2 adrenergic receptors be modified by G-protein modulation. This suggests that the drug effects on receptors be influenced by various conditions such as G-protein modulation.
Assuntos
Animais , Ratos , Sítios de Ligação , Encéfalo , Proteínas de Ligação ao GTP , Guanilil Imidodifosfato , Toxina Pertussis , Receptores Adrenérgicos alfa 2RESUMO
OBJECTIVE: The aim of this study is to determine effects of nefazodone on depression, anxiety, sleep and sexual function in depressive patients. SUBJECTS AND METHODS: This is an open, non-comparative, multi-center study. Antidepressant and other clinical effects of nefazodone were evaluated in 230 patients of 26 centers, aged 14 years or more, who met DSM-IV criteria to major depressive disorder or dysthymic disorder and didn't have other psychiatric disorders and were physically healthy. The clinical efficacy was assessed at week 1, 2, 4 and 8 using Clinical Global Improvement (CGI), Hamilton Depression Scale (HAM-D), Beck Depression Inventory (BDI), State and Trait Anxiety Inventory-State Anxiety (STAI-SA). Other clinical effects were assessed with Weekly Sleep Questionnaire, Sexual Functioning Questionnaire and GHQ-QOL-12, a scale for quality of life. Adverse drug reactions were checked with a questionnaire. Post-treatment effects of drug were compared with pre-treatment baseline condition. RESULTS: The response rates by Clincal Grobal Improvement and HAM-D after 8 weeks treatment were 62.4% and 75.2% respectively. Comparing to baseline, nefazodone was proved to have significantly higher antidepressant and antianxiety effects in depressive patients and it improved also sleep, sexual functions and quality of life. Both patients and physicians satisfied with the effects of drug. Adverse drug reactions were a few and not serious, and most of them disappeared as treatment continued. CONCLUSION: These results suggest that not only nefazodone has antidepressant effects and antianxiety effects, but also it improves sleep disturbance, sexual dysfunction and the quality of life in depressive patients. Adverse drug reactions were a few and not serious.