A concentration of 1 1 g/l was chosen for its ability to compete with saturated levels of exdotoxin or comparable ligand. (n?=?19) mice were tested in a Rota-Rod apparatus (Med-associates, St. Albans, VT, USA). Rota-rod acceleration was set to 4C40 revolutions per minute (RPM). Mice were placed on the Rota-rod for 3 trials of 5 minutes each with 15 minutes rest between trials. Time spent on the rod was measured. TLR4?/? mice showed superior overall performance in this task compared with TLR4+/+ mice (H) TLR4+/+ (n?=?24) and TLR4?/? (n?=?19) mice were tested in an elevated plus maze. Mice were placed in the maze for 5 minutes, and time spent in the open and closed arms was measured. No difference was observed between the experimental groups (I) TLR4+/+ (n?=?24) and TLR4?/? (n?=?19) mice were tested in an open field arena. Mice were place in the center of the industry for 15 minutes, and time spent in the center versus the periphery of the industry was measured. No difference was observed between the experimental PDK1 groups.(TIF) pone.0047522.s001.tif (2.4M) GUID:?EE8A3B8D-1D7B-4127-B7C5-754C77DCCB3A Physique Moexipril hydrochloride S2: CNS TLR4 inhibition affects anxiety but not spatial reference memory. Mice implanted with osmotic pumps that infuse either aCSF (n?=?10) or TLR4 antagonist (n?=?10) were trained for 5 days in the MWM with 4 trials per day. (A) Latency to reach the hidden platform was not significantly different between the experimental groups, (B) Swim distance was not significantly different between the experimental groups, while (C) Swim velocity was lower in TLR4 antagonist infused mice. (D) Path efficiency was significantly higher in TLR4-antagonist infused mice compared with aCSF infused mice at 48 hours after training (E) Mice implanted with osmotic pumps that infuse either aCSF (n?=?10) or TLR4 antagonist (n?=?10) were tested in an elevated plus maze. Mice were place in the maze for 5 minutes, and time spent in the open and closed arms was measured. TLR4 antagonist infused mice show altered stress response compared with aCSF infused mice (F) Mice implanted with osmotic pumps that infuse either aCSF (n?=?10) or TLR4 antagonist (n?=?10) were tested in an open field industry. Mice were place in the center of the industry for 15 minutes, and time spent in the center versus the periphery of the industry was measured. Moexipril hydrochloride TLR4 antagonist infused mice show altered stress response compared with aCSF infused mice (G) Excess weight of mice following surgical procedure and during the 4 weeks in which the pumps infused aCSF or TLR4 Moexipril hydrochloride antagonist into their lateral ventricles. Both experimental groups accumulated comparable weights during the month of behavioral tasks.(TIF) pone.0047522.s002.tif (2.5M) GUID:?940032BE-40AA-4C2D-BCBE-362D88C99C35 Figure S3: TLR4 expression had no impact on motivation, vision or motor function in spatial tasks. Mice of the following interventions were placed in the water maze while the platform was visible, and were allowed to reach the platform during 4 consecutive attempts for 3 days. (A) TLR4+/+ (n?=?24) and TLR4?/? (n?=?19) mice (B) Mice implanted with osmotic pumps that infuse either aCSF or Moexipril hydrochloride TLR4 antagonist (n?=?10 per group). No difference was observed between the different experimental groups.(TIF) pone.0047522.s003.tif (1.0M) GUID:?96F2A10E-1BD3-4454-A5F1-4B5D8FE05206 Physique S4: CREB, GluR1 and ERK are not altered in their expression levels in the cerebral cortex of TLR4?/? mice compared with TLR4+/+ mice. Brains from TLR4+/+ (n?=?8) and TLR4?/? (n?=?8) mice were dissected and cortices were removed. Tissues were then lysed, electrophoresed and immunoblotted against GluR1, CREB, ERK and their phosphorylated forms. Representative blots are offered for the cerebral cortex. No significant difference was observed between CREB, GluR1, ERK and their phosphorylated forms between TLR4?/? and TLR4+/+ mice. * p 0.05.(TIF) pone.0047522.s004.tif (1.3M) GUID:?B5D2BAA9-E7A1-4A02-B38C-BCC86A9E2BBC Abstract Toll-like receptors (TLRs) play essential roles in innate immunity and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain where they mediate responses to infection, stress and injury. Very little is known about the functions of TLRs in cognition. To test the hypothesis that TLR4 has a role in hippocampus-dependent spatial learning and memory, we used mice deficient for TLR4.