Alteration of Hematologic Parameters in Morphine-Dependent Rats by Long-Term Administration of Orexin Type 1 Receptor Antagonist

Background: Orexin peptides that are produced in the hypothalamic nuclei are involved in opioid dependence. Objectives: In the current study, we aimed to figure out the effect of orexin type 1 receptor (OXR1) antagonist on hematologic factors in morphinedependent rats. Patients and Methods: Male Wistar rats were rendered morphinedependent by subcutaneous injection of morphine sulfate (10 mg/Kg) at an interval of 12 hours twice a day for seven days. In the control and treatment groups, SB334867 vehicle and SB334867 were injected during postnatal days 1 to 30 (P1P30) daily and then before each morphine injection during for days. Data were analyzed using unpaired twotailed Student t-test and oneway analysis of variance (ANOVA). The defined level of statistical significance was P lt; 0.05. Results: Morphine increased white blood cell count (WBC), platelet cell count, and hematocrit. Application of SB334867 reduced several hematologic factors in morphinedependent rats, including mean corpuscular hemoglobin concentration (MCHC), WBC, and platelet count compared to morphinedependent rats. Conclusions:Inhibition of OXR1 may improve morphineinduced changes in hematologic factors in morphinedependent rats.