Aim To investigate the effect and mechanism of action of chronic morphine treatment on the neurosteroidogensis of primary cultured rat cerebral cortical neurons(CCNs).Methods The effect of morphine on the production of pregnenolone(PREG),dehydroepiandrosterone(DHEA),allopregnanolone(AP),pregnenlolone sulfate(PS)and dehydroepiandrosterone sulfate(DS)in cell culture media was measured by solid-phase extraction and LC-MS,with methyltestosterone(MT)or estrogen sulfate(ES)as internal standards.The dependence-like changes of CCNs were determined by testing the p-CREB level in the nuclear lysates using western blot.Results Compared with the control group,morphine treatment significantly reduced levels of PREG and DS respectively;opioid agonist DAMGO significantly reduced levels of PREG,DS and PS respectively,and increased the level of AP significantly.Compared with the morphine group,?-opioid-antagonist CTAP concomitant with morphine increased the level of PREG significantly.Compared with the control group,chronic morphine treatment or DAMGO treatment significantly increased the level of p-CREB in the CCNs.Compared with the morphine treatment group,?-antagonsit CTAP significantly reduced the level of p-CREB.Conclusion ?-opioid receptor mediated the inhibitory effect of morphine on levels of neurosteroids,and changes of neurosteroid levels might be related to morphine dependence.

Aim To investigate the effects of progesterone on morphine rewarding effect and levels of ?-receptor in hippocampus and striatum.Methods 32 male SD rats were designated to 4 groups randomly with 8 in each,including blank control group,morphine group,progesterone group and progesterone plus morphine group.Conditioned place preference(CPP) test was used to investigate the morphine rewarding effect,and immunohistochemistry was established to determine the levels of ?-receptor in hippocampus and striatum.Results Compared with those of blank control group,5 mg?kg-1 morphine successfully induced the formation of CPP(P

Objective To evaluate the changes in the expression of cytochrome cholesterol side chain cleavage enzyme (P450scc) in the brain of morphine-dependent rats. Methods Twenty-four male SD rats aged 4-8 months weighing 180-200 g were randomly divided into 3 groups (n = 8 each): group Ⅰ normal saline (group NS), group Ⅱ morphine dependence (group MD) and group Ⅲ morphine withdrawal (group MW). In group MD and MW, the rats were given intraperitoneally increasing doses of morphine starting from 5 mg/kg to 10, 15, 20, 30, 40 and 50 mg/kg twice a day for 7 days. In group NS, the rats were given equal volume of normal saline instead of morphine. The rats were decapitated 1 h after last injection in group NS and MD. In group MW, naloxone 2 mg/kg was given 1 h after last injection, and then the animals were decapitated 30 min after withdrawal symptoms were observed. The brains were immediately removed and the frontal cortex, hippocampus, striatum and thalamus were separated. The expression of P450see was determined by Western blot. Results The expression of P450scc in the frontal cortex, hippocampus and striatum was significantly decreased in group MD and MW compared with group NS (P<0.05). Conclusion The down-regulation of P450scc expression might be involved in the development of morphine dependence, but it is not involved in the morphine withdrawal.

Aim To investigate the effect of dehydroepiandrosterone(DHEA)on the levels of NR2B and GBR1 expressed in primary cultured rat cerebral cortical neurons.Methods Primary cultured rat cerebral cortical neurons were treated with DHEA of different concentrations (1,10,100 μmol·L~(-1))and the expression of amino acids receptor subunit NR2B and GBR1 were detected by immunocytochemistry.Results Compared with control group,the expression intensity of NR2B increased by 15.6%,19.9% and 49.4% after DHEA-L,DHEA-M and DHEA-H treatment(P<0.05 or P<0.01);the expression intensity of GBR1 increased by 14.5% and 58.5% after DHEA-M and DHEA-H treatment(P<0.05 or P<0.01).Conclusion DHEA can enhance the expression of neuron receptor subunit NR2B and GBR1.

Objective To investigate the effects of morphine dependence and withdrawal on neurosteroids and amino acid transmitters of rat amygdala. Methods Morphine dependence was induced by pretreatment with increasing doses of morphine for 7 days. Withdrawal was precipitated by naloxone (2mg/kg). Withdrawal syndromes were observed and scored. After decapitation, amygdala was dissected out. Nomadic and conjugated neurosteroids were extracted using liquid-liquid extraction and solid phase extraction. Concentrations of neurosteroids including dehydroepiandrosterone (DHEA), pregnenolone (PREG), allopregnanolone (AP), dehydroepiandrosterone sulfate (DHEAS) and pregnenolone sulfate (PREGS) were detected with HPLC-MS. Concentrations of glycine (GLY), glutamate (GLU) and gamma-aminobutyric acid (GABA) were quantitated by HPLC-ECD with pre-column OPA derivatization. Results Compared with saline control, the DHEA level in rat amygdala of morphine dependent group decreased by 33% (P＜0.01). Compared with naloxone control, the PREG and AP levels in rat amygdala of morphine withdrawal group increased by 45% (P＜0.05) and 42% (P＜0.05) respectively; the GABA level decreased by 18% (P＜0.01). Compared with morphine dependent group, the PREG and PREGS levels in rat amygdala of morphine withdrawal group increased by 60% and 40% respectively (P＜0.05); the glycine level decreased by 14% (P＜0.05). Conclusion The DHEA in rat amygdala may play a role in the development of morphine dependence but not involved in the manifestation of withdrawal symptoms. Other neurosteroids (including PREG, AP and PREGS) in rat amygdala seem to be involved in withdrawal but not in dependence. The synthesis and release of inhibitory amino acids in amygdala were depressed when withdrawal was precipitated by naloxone. The results suggest that different changes of neurosteroids and amino acids exist in stages of morphine dependence and withdrawal.

Objective: To investigate the effect of morphine dependence and withdrawal on the levels of neurosteroids in hippocampus of male rat.Methods: Rats were given (ip) increasing doses of morphine to form morphine physical dependence, withdrawal syndromes were precipitated by naloxone. The conditioned place preference (CPP) was used to establish morphine psychological dependence. The concentrations of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), pregnenolone (PREG), pregnenolone sulfate (PREGS), and allopregnanolone (AP) in rat hippocampus and plasma were quantified by liquid chromatography-mass spectrometry. Results:The rat model of morphine physical and psychological dependence were successfully established by ip increasing doses of morphine for 7 days and 5mg?kg~ -1 morphine for 10 days respectively. Compared with saline control group, morphine physical dependence increased DHEA and PREG contents in rat hippocampus (0.88?0.19/0.67?0.17,t=2.52,10.94?2.02/7.53?2.64,t=3.24,P

Aim To investigate the effects of progesterone on morphine rewarding effect and levels of endogenous opioid peptides in hypothalamus of rat brain. Methods Conditioned place preference(CPP)test was used to investigate the morphine rewarding effect, and radioimmunoassay (RIA) was established to deter-mine levels of ?-endorphin(?-EP), leu-enkephalin(L-EK) and dynorphin A(DynA) in hypothalamus of rat brain.Results Compared with NS control group, 5 mg?kg-1 morphine successfully induced the formation of CPP(P

OBJECTIVE: To promote the rational use of antibiotics.METHODS: A retrospectively analysis was conducted on the application of antibiotics in 4 186 discharge case histories in 2005.RESULTS: Of the total 4 186 cases,the application rate of antibiotics was 64.48%,among which,56.17% were prophylactic use of antibiotics and 5.89% used antibiotics without indication.The consumption of antibiotics occupied 45.90% of the total medicines consumed.The nosocomial infection rate was 4.16%,of which,23.56% were fungous infections.The incidence of adverse drug reactions was 2.56%.CONCLUSION: The rate for the prophylactic use of antibiotics in our hospital is on the high side,which may result in high incidences of drug resistant strains and nosocomial infections,therefore,measures should taken to tight the control of the administration of antibiotics.

Objective To investigate the expression of mRNAs for cholesterol side chain cleavage enzyme (p450 scc), 17?-hydroxylase / C17-20 lyase (P450 C17) and 3?-hydroxysteroid dehydrogenase (3?-HSD) in frontal cortex, amygdala, hippocampus, striatum and midbrain of morphine dependence rats.Methods Twenty-one male SD rats were randomly divided into 3 groups with 7 animals in each group: (1) control group (group C) ; (2) morphine dependence group (group D) and (3) morphine withdrawal group (group W). In group D and W the animals were given intraperitoneally increasing doses of morphine starting from 5 mg?kg-1 to 10, 15, 20, 30, 40 and 50 mg?kg-1 twice a day for 7 days. In group C the animals were given normal saline instead of morphine. In group C and D the animals were decapitated 1 h after last injection. In group W naloxone 2 mg?kg-1 was given 1h after last morphine injection, then the animals were decapitated 30 min after withdrawal symptoms were observed. The brains were immediately removed and the frontal cortex, amygdala, hippocampus, striatum and midbrain were separated. The expression of mRNAs for the three steroidogenic enzymes in the different brain regions of rats were determined by RT-PCR.Results The expression of P450scc mRNA in striatum and 3?-HSD mRNA in amygdala, striatum and frontal cortex decreased in group D compared with group C. The expression of 3?-HSD mRNA increased in morphine withdrawal group compared with group D.Conclusion The gene expression of steroidogenic enzymes decreases in some brain regions of morphine dependence rats, suggesting that endogenous neurosteroids might be involved in morphine dependence.

Aim To investigate the effect of progesterone on the levels of glutamate and ?-aminobutyric acid released from primary cultured rat cerebral cortical neurons.Methods Primary cultured rat cerebral cortical neurons were treated with PROG(10 ?mol?L-1) and the concentrations of amino acid in cell culture media at different time(0.5,1,1.5,2,24,36,48,72 h) were measured by OPA-mercaptoethanol precolumn derivatization technique and HPLC-FLD.Results Compared with control group,PROG treatment significantly reduced the levels of GLU at the time of 1,1.5,2,24,36,48,72 h(P