γ-氨基丁酸、荷包牡丹碱和L-谷氨酸钠对猫和家兔同侧和对侧图形视觉诱发电位的影响

EFFECT OF GABA, BICUCULLINE, AND L-GLUTAMATE ON THE PATTERN VISUAL EVOKED POTENTIAL (PVEP) IN IPSILATERAL AND CONTRALATERAL HEMISPHERE OF CAT AND RABBIT

在猫和家兔大脑半球一侧视区17/18交界处施加γ—氨基丁酸(GABA)、荷包牡丹碱和L—谷氨酸钠,以及用氯化钾和冷冻阻遏的方法,记录对侧和同侧皮层相应处图形视觉诱发电位(PVEP)的变化。讨论了GABA、荷包牡丹碱和L—谷氨酸钠对猫和兔的对侧和同侧PVEP的影响。

GABA, Bicuculline, L-Glutamate, KC1 and Reversible Cooling were applied at the cortical region of 17/18 border in one hemisphere of cat and rabbit. PVEP was recorded at the corresponding region in the contralateral and ipsila-teral hemisphere.(1) When 0.5M GABA was applied at the region of 17/18 border, the NI amplitude decreased 55% and 50%, the PI amplitude increased 230% and 104%, N1-P1 amplitude increased 43% and 34%, N1 latency increased 8% and 11% after 7 and 17 minutes in the contralateral PVEP of cat and rabbit, respectively. However, the NI amplitude decreased 53% and 79%, PI amplitude increased 12% and 5%, N1-P1 amplitude decreased 57% and 75% after 9 and 8 minutes in the ipsilateral PVEP of cat and rabbit, respectively. N1/P1 latencies did not change.(2) 5mM Bicuculline application at the region of 17/18 border produces a 78% and 39% decrease in NI amplitude, a 20% and 15% decrease in P1 amplitude, a 76% and 21% decrease in N1-P1 amplitude, an 8% and 5% increase in NI latency after 17 and 2 minutes in the contralateral PVEP of cat and rabbit, respectively. However, the amplitudes of N1, P1 and N1-P1 increased 187%, decreased 19% and increased 194%, respectively, after 5 minutes in ipsilateral PVEP of cat. N1/P1 latencies did not change.(3) 0.4M L-Glutamate application at the region of 17/18 border in cat produces a 75%, 12% and 59% decrease in N1, P1 and N1-P1 amplitudes, respectively, a 5% increase in N1 latency after 2 minutes in contralateral PVEP. However, the amplitudes of N1 , P1 arid N1-P1 increased 87%, decreased 17% and increased 55%, respectively, after 9 minutes in ipsilateral PVEP. N1/P1 latencies did not change.(4) 3.0M KC1 application at the region of 17/18 border in cat produces a decrease in N1,P1 and N1-P1 amplitudes of 38%, 39%, and 40%, respectively, an increase in N1 latency of 5% after 2 minutes in the contralateral PVEP, and a decrease in N1 , P1 and N1-P1 amplitudes of 87%, 86% and 84%, respectively, after 1 minute in ipsilateral PVEP. N1/P1 latencies did not change.(5) Cortical cooling at the surface of 17/18 border in cat produces a decrease in N1,P1 and N1-P1 amplitudes of 53%, 49% and 50% respectively, an increase in N1 latency of 5% after 7 minutes in contralateral PVEP. The cooling effect is reversed with N1-P1 amplitude recovery to 83% after 17 minutes.The effect of GABA, Bicuculline and L-Glutamate on the ipsilateral and contralateral PVEP in cat rabbit was discussed.