ABSTRACT
Objective To explore the role and mechanisms of 5-HT1Areceptors in the medial septum-diagonal band of Broca complex (MS-DB) in hemiparkinsonian rats. Methods Combined behavioral and electrophysiological studies were performed to assess the role of MS-DB 5-HT1Areceptors in working memory and hippocampal theta rhythm in rats with 6-hydroxydopamine (6-OHDA)lesions in the medial forebrain bundle (MFB).Results ① MFB lesions in the rats decreased choice accuracy in the T-maze rewarded alternation test. Intra-MS-DB injection of 5-HT1Areceptor agonist 8-OH-DPAT further decreased choice accuracy,while intra-MS-DB injection of 5-HT1Areceptor antagonist WAY-100635 increased choice accuracy in the lesioned rats.② MFB lesions in the rats decreased peak theta rhythm frequency. Intra-MS-DB injection of 8-OH-DPAT suppressed hippocampal theta rhythm and decreased normalized theta power,while intra-MS-DB injection of WAY-100635 induced theta rhythm and increased normalized theta power.Conclusion Blockade of MS-DB 5-HT1Areceptors can recover cognitive dysfunction in Parkinson's disease, which may be attributed to the enhancement of hippocampal theta rhythm.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the role of toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) in myocardial ischemia/reperfusion injury (MI/RI) by observing the dynamic expression changes at mRNA and protein levels early after myocardial ischemia/reperfusion (I/ R).</p><p><b>METHODS</b>The Wistar rats were randomly divided into Sham and I/R group (n = 42), and killed according to different reperfusion time (1, 2, 4, 6, 12, 24 h and 7 d). Structural and morphous changes of myocytes were observed under optical microscope. The mRNA and protein levels of TLR2 and TLR4 were detected using real-time PCR (RT-PCR). Monocyte chemokine protein-1 (MCP-1) and interleukine-6 (IL-6) mRNA levels were measured by reverse transcriptase-polymerase chain reaction (rt-PCR).</p><p><b>RESULTS</b>(1) With the extension of reperfusion time, the myocardial infarct size increased smoothly, and reached the plateau at 4 h, then stayed in the platform. After reperfusion for 7 d, the ventricular had been remodeled. (2) At the beginning of reperfusion, myocardial structure showed no significant change in Sham group, but had different degrees of injury in I/R group. In rats of the group reperfused for 7 d the left ventricular remodeling could be visible. (3) Compared to sham group,TIR2, TLR4, MCP-1, IL-6 mRNA level were increased in myocardium in I/R group. TLR2 and TLR4 both peaked at 4 h of reperfusion, IL6 peaked at 6 h, followed by a gradually decrease. TLR4 and IL-6 mRNA levels rose again at 7 d. MCP-1 level in I/R group remained fairly with sham group at the beginning of reperfusion, and markedly elevated at 7 d.</p><p><b>CONCLUSION</b>Expression of TLRs mRNA in myocardium during early after myocardial ischemia/reperfusion increased rapidly and activated TLRs might play an important role in MI/RI through promoting the generation of inflammatory factors. At the late reperfusion, TLRs levels raise again and the expression of inflammatory factors increase once again, Those may probably affect the remodeling of ventricular, and injure myocardial structure and function.</p>
Subject(s)
Animals , Male , Rats , Chemokine CCL2 , Metabolism , Disease Models, Animal , Interleukin-6 , Metabolism , Myocardial Reperfusion Injury , Metabolism , Rats, Wistar , Toll-Like Receptor 2 , Metabolism , Toll-Like Receptor 4 , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the protective effects of carnosine against experimental closed head injury (CHI) in mice.</p><p><b>METHODS</b>The CHI model was established by free-falling weight-drop. Carnosine (250 mg/kg or 500 mg/kg) was administered intraperitoneally 30 min before brain trauma, then q.d for 7 d; while normal saline was administrated for control group. The neurological defect was evaluated by neurological severity score (NSS) within 7 d; the survival rate and the histological alternations were observed.</p><p><b>RESULTS</b>Carnosine prevented the body weight loss of mice at dose of 500 mg/kg; significantly increased the survival rate, and reduced the neurological defect and histological damage at dose of 250 and 500 mg/kg.</p><p><b>CONCLUSION</b>Carnosine can attenuate closed head injury in mice.</p>