AIM and METHODS: To investigate the effect of electrical stimulation of ventlal septal area (VSA) on discharge of pyrogen - treated thermosensitive neurons in preoptic anterior hypothalamus (POAH) region, the discharging rate of thermosensitive neurons in the POAH region of 32 New Zealand white rabbits were recorded by using extracellular microelectrode techinque. RESULTS: (1) Intraceretroventricularly (i c v) injection of interleukin - 1?(IL - 1?) caused decrease of discharging rate of warm - sensitive neurons and increased in discharging rate of cold - sensitive neurons in POAH regions. (2) These effects could be reversed by electrical stimulation of VSA. CONCLUSION: VSA may play a central role of negative regulation in thermoregulation of pyrogen - treated animal.

AIM and METHODS: To investigate the functional connection between the preoptic anterior hypothalamus (POAH) and the ventral septal area (VSA) in fever mechanism, the firing rates of thermosensitive neurons in the VSA of 26 New Zealand white rabbits were recorded using extracellular microelectrode technique. RESULTS: The firing rates in both types of thermosensitive neurons in the VSA had no significant changes after intracerebroventricular (icv) injection of artificial cerebrospinal fluid(ACSF). When interleukin-1β (IL-1β) was given (icv), the firing rate of the warm-sensitive neurons was increased significantly and that of the cold-sensitive neurons was decreased remarkably. The effects of IL-1β on the changes of firing rate in thermosensitive neurons of the VSA were reversed by electrical stimulation of the POAH. CONCLUSION: The roles of positive and negative thermoregulatory centers in the interaction between the POAH and VSA are closely linked during endogenous pyrogen induced fever.

Abstract］　AIM and METHODS:The recent work from our laboratory showed that ventral septal area (VSA) played a negative-regulatory central role in thermoregulation during endogenous pyrogen-induced fever. In order to further investigate the role of VSA in the antipyretic mechanism, we observed the effects of electrical stimulation of VSA on firing characteristics of thermosensitive neurons in preoptic anterior hypothalamus (POAH) by using extracellular microelectrode technique on 32 New Zealand white rabbits treated with interleukin-1 β (IL-1β) intracerebroventriculary (ICV). RESULTS:(1)Injection of IL-1β decreased discharging rate of warm-sensitive neurons in POAH. Electrical stimulation of VSA remarkably decreased thermosensitive coefficient of warm-sensitive neurons. (2)Injection of IL-1β caused increase in discharging rate of cold-sensitive neurons in POAH. Electrical stimulation of VSA remarkably increased thermosensitive coefficient of cold-sensitive neurons. CONCLUSTION:VSA may have an antipyretic effect through affecting the firing characteristics of thermosensitive neurons in POAH during IL-1β-induced fever.

AIM: To study the influence of glycine(GLY) on lipopolysaccharide-binding protein(LBP) mRNA expression induced by LPS. METHODS: The level of LBP mRNA expression in liver tissues of rats was examined by RT-PCR,and the effects of glycine on LBP mRNA expression in liver tissues of rats induced by LPS were investigated. RESULTS: The level of LBP mRNA expression in hepatic tissue of rats in the LPS group was significantly higher than that in the control group( P

AIM: To investigate the protective effect of Siduqing, a Chinese medicine, on LPS-induced myocardium injury in mice and its mechanisms. METHODS: Mice were divided into 4 group: control, LPS, Siduqing treatment and Siduqing group, and administered intragastrically with Siduqing decoction or distilled water (0 2 mL/10 g) twice a day for 3 days, two hours after Chinese herbal medicine treatment on day 3, LPS (30 mg/kg) or normal saline was injected intraperitoneally. The serum creatine kinase (CK) and myocardial superoxide dismutase (SOD) activities were determined, and myocardial tumor necrosis factor ? (TNF?) and malondialdehyde (MDA) contents were also detected. In addition, the histological changes and ultrastructure of heart were examined. RESULTS: Histological examination showed edema in myocardium and architectural disarray at 12, 24 h after LPS injection, mitochondrial swelling, condensation and margination of chromatin, irregular nuclear envelope and loss of contractile filaments at 24 h post LPS administration, while Siduqing treatment attenuated the above pathological changes of myocardium. CK activity in serum and myocardial TNF? content were higher in LPS group than control and Siduqing treatment group. Myocardial SOD activity in siduqing treatment group was higher than that in LPS group, but there was no difference in myocardial MDA content between control, LPS and Siduqing treatment group. CONCLUSION: These data suggest that Siduqing protects myocardium against LPS- induced injury via inhibiting myocardial TNF? production.

AIM: To investigate the mechanisms by which siduqing, a Chinese medicine, protects against lipopolysaccharide (LPS)-induced acute renal dysfunction. METHODS: Mice were divided randomly into control, LPS, siduqing treatment and siduqing groups, and treated intragastrically with siduqing at a dose of (1 000) g/L (0.2 (mL/10 g) body weight) or distilled water (0.2 (mL/10) g body weight) twice a day for 3 days, LPS (30 mg/kg) or normal saline was injected intraperitoneally on day 3, followed by intragastrical administration with siduqing at a dose of (1 000) g/L (0.2 (mL/10 g) body weight) or distilled water (0.2 (mL/10 g) body weight). Blood was collected for determining urea nitrogen (BUN) and creatinine (Cr) contents, renal tissue for examining superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. In addition, electron microscopy was used to examine the ultrastructure changes in kidney, and RT-PCR was performed to detect renal intercellular adhesion molecule-1 (ICAM-1) mRNA expression. RESULTS: LPS significantly increased serum urea nitrogen (BUN) and creatinine (Cr) contents, and produced an obvious pathological change in renal ultrastructure, which were significantly attenuated by siduqing treatment. Moreover, siduqing treatment increased renal SOD activity, also markedly suppressed an increase in renal MDA production and ICAM-1 mRNA expression induced by LPS. CONCLUSION: These results suggest that siduqing protects against LPS-induced acute renal injury through inhibiting ICAM-1 mRNA expression, enhancing renal SOD activity and attenuating oxidant stress.

AIM: To investigate the differences of Alzheimer's disease(AD)-related parameters in the SAM-P/8, the SAM-R/1 and the Kunming mice.METHODS: The changes of ethology, neurobiochemistry (true choline esterase, TchE), ultrastructure and gene expression(gene chips) were determined in mice of three groups: SAM-P/8 mice (n=14), SAM-R/1 mice (n=14) and Kunming mice (n=14), which were 6 months old[weight(20?5)g].RESULTS: The SAM-P/8 mice had the inabilities of learning and memory compared with the SAM-R/1 mice and the Kunming mice (P

AIM and METHODS:To investigate the effect of electrical stimulation of VSA on the firing of thermosensitive neurons in preoptic anterior hypothalamus (POAH), the firing rate of thermosensitive neurons in POAH of 20 New Zealand white rabbits was recorded by using extracellular microelectrode techinque. RESULTS:(1)Electrical stimulation of ventral septal area (VSA) caused a significant increase in firing rate of warm-sensitive neurons in the preoptic area of the anterior hypothalamus(POAH).(2) The firing rate of cold-sensitive neurons was decreased remarkably in the POAH by electrical stimulation of VSA. CONCLUSION:VSA may play a controlling role in the thermoregulation through altering the firing rate of thermosensitive neurons in the POAH.

AIM: The present study was undertaken to explore the effects of ?-MSH on partial biological activities of LPS. METHODS:Colorimetric method was used for the measurement of hydrogen peroxide(H_2O_2) production in mouse peritoneal macrophages, the apoptosis of polymorphonuclear leukocytes(PMNs) and the binding of LPS to monocytes were studied with flow cytometry. RESULTS: It was found that LPS strongly stimulated macrophages to release H_2O_2. When macrophages were cultured with ?-MSH in the presence of LPS, the H_2O_2 release was markedly suppressed (P0.05). In the presence of LPS, however, ?-MSH significantly promoted the apoptosis of PMNs (P

AIM and METHODS: To investigate the effect of electrical stimulation of VSA on the firing of thermosensitive neurons in preoptic anterior hypothalamus (POAH), the firing rate of thermosensitive neurons in POAH of 20 New Zealand white rabbits was recorded by using extracellular microelectrode techinque. RESULTS: (1)Electrical stimulation of ventral septal area (VSA) caused a significant increase in firing rate of warm-sensitive neurons in the preoptic area of the anterior hypothalamus(POAH).(2) The firing rate of cold-sensitive neurons was decreased remarkably in the POAH by electrical stimulation of VSA. CONCLUSION: VSA may play a controlling role in the thermoregulation through altering the firing rate of thermosensitive neurons in the POAH .