AIMTo study the possibility that responses of fever and discharge of neurons in PVN to intraperitoneal administration of LPS are mediated by vagal afferents.

METHODSRectal temperature of rat was detected by digital temperature detecting instrument. Glass micropipette placed in PVN was used to record unit discharges of neurons in it, before and after LPS was injected into PVN in normal rats and vagotomy rats.

RESULTSThe rectal temperature change value in vagotomy LPS group was significantly decreased compared with that in sham LPS group, and there was striking difference between them (P < 0.05). The discharges of neurons in PVN was increased in the normal rat in response to LPS. The discharges of neurons in PVN had no significant change in the vagotomy rats in response to LPS.

CONCLUSIONThe results indicate that vagus nerve may be one of the pathways of peripheral LPS signal communicating to CNS.

Animals ; Diaphragm ; innervation ; Fever ; chemically induced ; physiopathology ; Lipopolysaccharides ; Male ; Neurons ; physiology ; Paraventricular Hypothalamic Nucleus ; physiopathology ; Rats ; Rats, Wistar ; Vagotomy, Truncal

AIMTo determine whether bombesin prevents IFN-alpha-induced fever and it's possible mechanism.

METHODSEffects of BN on changes in body temperature and arginine vasopressin(AVP) content in the ventral septal area(VSA) and hypothalamus were measured in the rats following intracerebroventricular (ICV) injection of IFN-alpha.

RESULTS(1) IFN-alpha produced a dose-dependent rise in colonic temperature simultaneously with increase in AVP content in the VSA in the rats. (2) BN produced a dose-dependent hypothermia and significantly elevated AVP content in the VSA in rats. (3) BN injected intracerebroventricularly at 30 min after IFN-alpha prevented the increase in colonic temperature which recovered to the control level as well as AVP content in the VSA in rats at 150 min.

CONCLUSIONAVP in the VSA may play a role in IFN-alpha-induced fever. AVP in the VSA may play a partial role in the BN antipyretic action and hypothermic action.

Animals ; Arginine Vasopressin ; metabolism ; Body Temperature Regulation ; drug effects ; Bombesin ; pharmacology ; Brain ; drug effects ; metabolism ; Fever ; chemically induced ; physiopathology ; Interferon-alpha ; adverse effects ; Male ; Rats ; Rats, Wistar

This study examined the effect of experimentally induced fever on the pharmacokinetics of cefepime (75 mg/kg BW) administered intramuscularly to six rabbits. The study was carried out in two consecutive phases separated by a two-week washout period. An infection was induced by an intravenous inoculation of 5 x 10(8) colony-forming units of Escherichia coli 24 h before the pharmacokinetic investigation. A quantitative microbiological assay was employed to measure the plasma cefepime concentrations using an agar-gel diffusion method with Bacillus subtilis ATCC 6633 as the test organism. Twenty-four hour after the injection, the rectal temperature in the infected animals increased by 1degrees C. There was a significant reduction in the elimination halflife by 21.8% in the febrile rabbits compared to healthy animals. In addition, the infection significantly increased the peak plasma concentrations by 11.9%, the mean residence time by 19.9%, the area under the plasmaconcentration- time curve by 53.6% and the area under the moment curve by 62.3%. In conclusion, the endotoxin-induced febrile state produced significant changes in the plasma levels as well as some of the pharmacokinetic variables of cefepime in rabbits.
Animals ; Anti-Bacterial Agents/*administration&dosage/blood/*pharmacokinetics ; Area Under Curve ; Cephalosporins/*administration&dosage/blood/*pharmacokinetics ; Endotoxins/pharmacology ; Escherichia coli Infections/drug therapy/physiopathology ; Fever/chemically induced/*physiopathology ; Half-Life ; Injections, Intramuscular ; Male ; Rabbits

OBJECTIVETo observe the effect of ruthenium red (RR) on the body temperature of rats with lipopolysaccharide (LPS)-induced fever and investigate the possible mechanism.

METHODSRat models of fever were established with lipopolysaccharide and the effects of RR at different doses were observed on the body temperature of the rats and the content of TRPV4 in the hypothalamus.

RESULTSCompared with those in LPS group, the rats with LPS-induced fever receiving RR treatment showed a dose-dependent lowering of the body temperature. The rats with RR treatment had lower body temperature than those with saline injection. The content of TRPV4 in the saline group was significantly higher than that in RR+LPS and RR group.

CONCLUSIONSRR inhibits LPS-induced fever in rats and regulates the hypothalamal expression of TRPV4 channels, which may participate in the maintenance of normal body temperature.

Animals ; Blotting, Western ; Body Temperature ; drug effects ; Dose-Response Relationship, Drug ; Fever ; chemically induced ; metabolism ; physiopathology ; Hypothalamus ; drug effects ; metabolism ; Lipopolysaccharides ; Male ; Rats ; Rats, Sprague-Dawley ; Ruthenium Red ; pharmacology ; TRPV Cation Channels ; biosynthesis

In order to discover the mechanism of Xuebijing oral effervescent tablet (XBJOET) to treat infectious diseases, the effect of XBJOET on endotoxin induced rabbit fever and disseminated intravascular coagulation (DIC) was investigated. Auricle microcirculation in rabbit was detected by laser speckle blood perfusion imager system; coagulation function was measured by coagulation analyzer, fibrinolytic system was quantified by Elisa assay and micro thrombosis in tissues was observed with HE staining under light microscope. The results demonstrated that the body temperature of rabbit decreased significantly at 1-3 h after administration with 4.8, 2.4 and 1.2 g x kg(-1) XBJOET to endotoxin induced DIC rabbit model, the auricle microcirculation blood flow in model group (54.45 +/- 14.53) PU was lower than that in control group (77.18 +/- 12.32) PU. The auricle microcirculation blood flow increased markedly and there was significant difference between model group and 1.2 g x kg(-1) XBJOET group. There was significant difference between model group and control group in the content of PAI1 and FIB. The PAI1 levels in model and control groups were (30.48 +/- 2.46) ng x mL(-1) and (20.93 +/- 3.25) ng x mL(-1), respectively. The FIB levels in model and control group were (3.34 +/- 1.09) g x L(-1) and (4.84 +/- 1.10) g x L(-1), respectively. The content of PAI1 in rabbit plasma decreased notably, there were significant differences between model group and 4.8, 2.4 g x kg(-1) XBJOET groups. On the contrary the content of FIB increased. XBJOET possessed pharmacological activities of curing infectious fever and DIC, the mechanism of which is related to amelioration of microcirculation disturbance, inhibition of fibrinolytic system activation and coagulation and micro thrombosis elimination.
Administration, Oral ; Animals ; Blood Coagulation ; drug effects ; Body Temperature ; drug effects ; Disseminated Intravascular Coagulation ; blood ; chemically induced ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Ear Auricle ; blood supply ; Endotoxins ; Female ; Fever ; chemically induced ; drug therapy ; physiopathology ; Fibrinogen ; metabolism ; Male ; Microcirculation ; Partial Thromboplastin Time ; Plasminogen Activator Inhibitor 1 ; blood ; Prothrombin Time ; Rabbits ; Tablets ; Thrombosis ; pathology

OBJECTIVETo study the analgesic, antipyretic and anti-inflammatory effect of Bailian Caogen granule.

METHODThe antipyretic effects of Bailian Caogen granule was evaluated in rabbit fever model induced by peptone. The analgesic effect of the drug was studied with pain model of mice induced by acetic acid and hot plate, The severity of oedema in inflamed animal was observed to study the anti-inflammatory effects of Bailian Caogen granule.

RESULTBailian Caogen granule could obviously inhibit the fever of rabbits. The number of writhing induced by acetic acid was reduced and the pain threshold of mice was increased by Bailian Caogen granule. Bailian Caogen granule also had anti-inflammatory activity against xylene-induced mouse ear swelling and carrageenin-induced rat paw edema.

CONCLUSIONBailian Caogen granule has significant analgesic, antipyretic and anti-inflammatory activities.

Acetic Acid ; Analgesics, Non-Narcotic ; pharmacology ; Animals ; Body Temperature ; drug effects ; Coptis ; chemistry ; Drug Combinations ; Drugs, Chinese Herbal ; pharmacology ; Edema ; pathology ; prevention & control ; Female ; Fever ; physiopathology ; prevention & control ; Glycyrrhiza uralensis ; chemistry ; Hot Temperature ; Hyperalgesia ; etiology ; physiopathology ; prevention & control ; Male ; Mice ; Pain ; chemically induced ; physiopathology ; prevention & control ; Pain Threshold ; drug effects ; Phellodendron ; chemistry ; Plants, Medicinal ; chemistry ; Pueraria ; chemistry ; Rabbits ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effect of Guizhi Tang and its active components on the fever induced by EP3 receptor agonist sulprostone in rats.

METHODThe rise in body temperature evoked by a LCV(lateral cerebroventricle)-injection of sulprostone was compared with that of sulprostone induced-fever rats pretreated with Guizgi Tang and its active compounds, cinnamaldehyde, cinnamic acid and total glucosides of paeony.

RESULTPretreatments with Guizhi Tang and cinnamaldehyde inhibited the rise in body temperature induced by sulprostone, while cinnamic acid tended to augment the fever. The sulprostone-induced fever was blocked by an ip pretreatment of total glucosides of paeony even below the basement.

CONCLUSIONPresent data suggest that interruption with the down-stream events of EP3 receptor may contribute to the antipyretic action of Guizhi Tang, cinnamaldehyde and the total glucosides of paeony, while cinnamic acid may have no such effect.

Acrolein ; analogs & derivatives ; isolation & purification ; pharmacology ; Analgesics, Non-Narcotic ; isolation & purification ; pharmacology ; Animals ; Body Temperature ; drug effects ; Cinnamates ; isolation & purification ; pharmacology ; Dinoprostone ; analogs & derivatives ; Drug Combinations ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Fever ; chemically induced ; physiopathology ; Glucosides ; isolation & purification ; pharmacology ; Male ; Paeonia ; chemistry ; Plants, Medicinal ; chemistry ; Rats ; Rats, Wistar ; Receptors, Prostaglandin E ; agonists ; Receptors, Prostaglandin E, EP3 Subtype