Low-Frequency Stimulation Prevents Kindling-Induced Impairment through the Activation of the Endocannabinoid System

<div>The effects of low-frequency stimulation (LFS), kindling, cannabinoid 1 (CB1) agonist (WIN55-212-2), and CB1 antagonist (AM251) on spatial memory in the Morris water maze (MWM) test. (a) Traveled distance percentage in the target quadrant (Q4) and (b) time percentage in the Q4. In the probe test phase of the MWM, the submerged platform was removed from the Q4. Every rat was allowed to swim for 60 seconds, and its traveled distance and spent time in the Q4 were measured. Decreased amounts, in comparison to the control group, indicate spatial memory impairment. Data are shown as <span class="nowrap"><svg height="9.10327pt" id="M12" style="vertical-align:-0.3499298pt" version="1.1" viewbox="-0.0498162 -8.75334 67.6442 9.10327" width="67.6442pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M797 0V26C739 32 732 36 732 103V296C732 394 682 449 605 449C576 449 550 437 529 423C504 407 475 389 446 366C425 418 382 449 334 449C303 449 279 437 253 421C222 403 201 385 180 371V452C135 432 85 419 41 411V388C99 379 102 374 102 310V103C102 38 93 32 27 26V0H238V26C189 32 180 38 180 103V338C210 363 250 390 289 390C351 390 377 348 377 275V103C377 37 368 32 306 26V0H520V26C465 32 456 38 456 101V296C456 314 455 326 453 338C491 369 529 390 565 390C628 390 653 345 653 274V107C653 36 642 32 583 26V0H797Z"></path></g><g transform="matrix(.013,0,0,-0.013,10.595,0)"><path d="M380 106C343 72 306 56 265 56C195 56 116 112 115 248C235 252 361 262 377 265C396 269 400 277 400 297C400 374 333 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96 71 90C59 80 50 67 49 57C48 45 52 36 66 23C80 9 123 -12 169 -12C221 -11 288 15 342 59C403 109 431 165 431 225C431 308 366 395 238 395C212 395 165 379 127 364L153 550Z"></path></g></svg> (compared to the kindled group); <sup>&amp;</sup><svg height="11.7782pt" id="M15" style="vertical-align:-3.42938pt" version="1.1" viewbox="-0.0498162 -8.34882 44.5261 11.7782" width="44.5261pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M570 304C570 398 525 448 414 448C385 448 343 445 312 434L329 511L321 518C297 504 262 482 244 460L233 411C195 397 159 381 128 358L135 332C160 347 189 360 224 373L111 -147C97 -210 84 -218 17 -231L13 -257L254 -247L259 -218L233 -216C183 -212 177 -202 189 -142L218 -1C238 -10 266 -12 283 -12C351 3 429 48 483 105C543 168 570 242 570 304ZM482 289C482 161 380 33 304 33C278 33 248 51 233 69L303 396C326 400 352 403 369 403C428 403 482 380 482 289Z"></path></g><g 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BioMed Research International

fig3

Figure 3

Figure 3: Low-Frequency Stimulation Prevents Kindling-Induced Impairment through the Activation of the Endocannabinoid System 