Effects of er-long-zuo-ci-wan on the spontaneous activities of auditory central nucleus in rat model of tinnitus induced by salicylate acid / 中国应用生理学杂志

<p><b>AIM</b>Observe the effects of er-long-zuo-ci-wan (EIZCW, a compound of Chinese Traditional Medicine) on the spontaneous discharge of external cortex of inferior colliculus (ICx) and secondary auditory cortex (AII) of chronic tinnitus model rats induced by salicylate acid, to explore the neural mechanisms underlying ELZCW preventing tinnitus.</p><p><b>METHODS</b>30 adult SD rats were involved and divided into three groups, normal control group, chronic tinnitus model group and ELZCW prevention group. Extracellular recording techniques and stereotaxic method were used. The spontaneous spikes were recorded and analyzed from ICx and all in different group rats. The average rate of spontaneous discharge and the interspike interval histogram of spontaneous activities were used as indexes.</p><p><b>RESULTS</b>(1) Compared with normal control group, the average rate of spontaneous discharge recorded from the ICx in the chronic tinnitus model group increased significantly (4.57 +/- 0.54 Hz vs. 3.14 +/- 0.40 Hz, P < 0.05). Furthermore analysis showed that the discharge rate of short spike interval from the ICx in the chronic tinnitus model group increased than that of the normal group (0-40 ms: 58% vs. 40%; 0-4 ms: 9% vs. 5%). And there was an increasing tendency of the average rate of spontaneous discharge recorded from the AII in the chronic tinnitus model group compared with that in the normal group. (2) Compared with the chronic tinnitus model group, the average rate of spontaneous discharge recorded from the ICx and AII in the ELZCW prevention group significantly decreased than that in the chronic tinnitus model group (ICx: 2.41 +/- 0.21 Hz vs. 4.57 +/- 0.54 Hz, P < 0.01. AII: 2.24 +/- 0.24 Hz vs. 4.57 +/- 0.54 Hz , P < 0.01). And the discharge rate of short spike interval from the ICx and AII in the chronic tinnitus model group decreased than that in the normal control group (ICx: 0-40 ms 50% vs. 58%, 0-4 ms 4% vs. 9%. All: 0-22 ms: 24% vs. 31%, 0-8 ms 19% vs. 16%).</p><p><b>CONCLUSION</b>If the increasing of the spontaneous activities of ICx and AII in chronic tinnitus rats means tinnitus, the use of ELZCW could decrease this kind of changes.</p>

Effect of electrical stimulation of the primary auditory cortex on the spontaneous activities of the external nucleus of the inferior colliculus in a rat model of tinnitus induced by salicylate acid / 生理学报

This study aims to investigate corticofugal modulation on spontaneous activities of the external nucleus of the inferior colliculus (ICx) in a salicylate acid (SA) induced tinnitus rat model by the stimulation of the primary auditory cortex (AI). Extracellular recording techniques and stereotaxic method were used. The spontaneous activities of a single unit were recorded from the left ICx after electrical stimulation was given to the left AI of the rats duplicated as acute SA models. The average rate of spontaneous discharge and the interspike interval histogram of spontaneous activities were used as indices. The single unit spontaneous discharges of the same unit of ICx before and after AI stimulation were observed. There was an inhibitory effect of AI stimulation on the activities of the high discharge unit [(8.75+/-2.70) Hz vs (5.06+/-2.01) Hz] and a facilitatory effect on the low discharge unit [(1.41+/-0.45) Hz vs (2.46+/-0.79) Hz]. In the normal group, there was a restraining effect on the average rate of spontaneous discharge of the ICx after AI stimulation. The average rate of spontaneous discharge changed from (3.66+/-0.84) Hz to (2.47+/-0.43) Hz in the first hour after AI stimulation and then recovered within 2-4 h. And the discharge rate of the spike interval within 0-20 ms decreased (17% vs 7.3%, 11.2%) in the first 2 h and recovered 3-4 h after AI stimulation. The discharge rate of the spike interval within 0-6 ms (short interval) recovered 2 h after AI stimulation. In the acute SA model group, the average rate of spontaneous discharge recorded from the ICx decreased from (7.48+/-0.85) Hz to (3.38+/-0.39) Hz in the first hour after AI stimulation and the suppression effect remained 4 h (P<0.05). There was no difference in the average rate of spontaneous discharge between the acute SA model group and the normal group at 2-4 h after AI stimulation. The suppression effect after AI stimulation on the 0-20 ms interval spikes in the ICx lasted 4 h, while that on the shorter interval (0-6 ms) spikes recovered in the 3rd hour after AI stimulation in acute SA model group. It is concluded that the high average spontaneous discharge rate of ICx in acute SA model decreases significantly by AI stimulation, and the suppression effects on the shorter interval spikes recovers in the 3rd hour after AI stimulation. It might be inferred that stimulation of AI, through exciting the auditory descending projections, could remit the increased spontaneous discharge of ICx induced by SA that may relate with tinnitus in a period of time.

Study of the antiulcer effect of pantoprazole / 中国临床药理学与治疗学

Aim To evaluate the effects of pantoprazole on various experimental acute ulcer inrats and mice. Methods The model of a gastric ulcer of rats or mice was caused bystree- induced ulcer and ligatel pylurus-induced ulcer. Results & Conclusions At adose of 5, 10, 20 mg? kg-1 of Pantoprazole can markedly decrease the ulcer index ofstree-induced ulcer. Pantoprazole(4, 8, 16 mg? kg -1 ) significantly decrease the areaof ligated pylorus-induced gastric ulcer. It was also found that pantoprazole caninhibit the output of basic gastric acid.