전기자극에 대한 역돔, Oreochromis niloticus［Linnaeus］의 심전도를 구명하기 위하여, 어체내에 전극을 삽입하여 3 가지 전기자극원(20, 30, 40 Vp ; 10 msec)으로 실험어에 자극을 가하였을 때의 심전도를 서간과 야간으로 구분하여 60분간 조사한 심박수와 생체전위를 자극 전(마취상태, 안정상태)과 자극 후(자극-회복상태, 회복상태)로 구분하여 비교 분석한 결과는 다음과 같다. 1. 역돔은 마취 후 3 분 뒤에 안정상태에 도달하였고, 안정상태에서의 평균상심박수는 서간에 45.8 beat/min, 야간에 45.0 beat/min였고, 평균생체전위는 서간에 1.76 μ V, 야간에 1.75 μ V였다. 2. 자극별 평균심박수는 ① 자극-회복상태에서 전기자극이 20 Vp인 경우, 서간에 34.9 beat/min, 야간에 33.4 beat/min였고, 30 Vp인 경우, 서간에 36.8 beat/min, 야간에 36.0 beat/min였으며, 40Vp인 경우 서간에 38.0 beat/min, 야간에 36.4 beat/min로 나타났다. ② 회복상태에서 전기자극이 20 Vp인 경우, 서간에 45.5 beat/min, 야간에 45.1 beat/min였고, 30 Vp인 경우, 서간에 47.9 beat/min, 야간에 49.0 beat/min 였으며, 40 Vp인 경우, 서간에 51.4 beat/min, 야간에 50.7 beat/min로 나타났다. 3. 자극별 평균생체전위는 ① 자극-회복상태에서 전기자극이 20Vp인 경우, 서간에 2.54μ V 야간에 2.39μ V였고,30Vp인 경우, 서간에 3.30μ V, 야간에 2.30 μ V였으며, 40Vp 인 경우 서간에 6.05 μ V, 야간에 3.23 μ V로 나타났다. ② 회복상태에서 전기자극이 20 Vp인 경우, 서간에 1.92 μ V, 야간에 1.95 μ V 였고, 30 Vp인 경우, 서간에 2.78 μ V, 야간에 2.21 μ V 였으며, 40 Vp인 경우 서간에 3.60μ V 야간에 2.98μ V로 나타났다.

The response of electrocardiogram(ECG) of Nile tilapia, Oreochromis niloticus [Linnaeus] was studied to the electric stimulus which was given to a certain part of body The experiments were performed in such a way that three levels of electric stimulus (20, 30, 40 Vp ； 10 msec) were given to fishes with electrode inserted into their bodies and then their ECGs were recorded continuously for 60 minutes in the water temperature of 16~18℃ The results of the experiments were divided by day and night, and then were analyzed by experimental conditions as follows; 1. Nile tilapia reached a stable condition within 3 minutes after the electrode inserted into their bodies during anesthesia. In stable condition, the heart rates average was 45.8 beat/min during daytime and 45.0 beat/min at night. The action potentials average was 1.76 mutextrmVduring daytime and 1.75 mutextrmV at night. 2. The heart rates average by three levels of electric stimulus were ① In the stimulus condition, the heart rates were 34.9 beat/min during daytime and 33.4 beat/min at night for the 20 Vp level, 36.8 bea/min during daytime and 36.0 beat/min at night for the 30 Vp level, and 38.0 beat/min during daytime and 36.4 beat/min at night for the 40Vp level. ② In the recovery condition, the action potentials were 45.5 beat/min during daytime an 45.1 beat/min at night for the 20Vp level, 47.9 beat/min during daytime and 49.0 beat/min at night for the 30Vp level, and 51.4 beat/min during daytime and 50.7 beat/min at night for the 40Vp level 3. The action potentials average by three levels of electric stimulus were, ① In the stimulus condition, action potentials were 2.54 mutextrmV during daytime and 2.39 mutextrmV at night for the 20 Vp level, 3.30 mutextrmV during daytime and 2.30 mutextrmV at night for the 30 Vp level and 6.05 mutextrmV during daytime and 3.23 mutextrmV at night for the 40 Vp level. ② In the recovery condition, action potentials were 1.92 mutextrmV during daytime and 1.95 mutextrmV at night for the 20 Vp level and 2.78 mutextrmV during daytime and 2.21 mutextrmV at night for the 30Vp level and 3.6 0 mutextrmV during daytime and 2.98 mutextrmV at night for the 40 Vp level.

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