The Effects Of Isoflurane On The Learning And Memory Functions Of Sprague-Dawley Rat's Offspring Offspring During Early Gestation Period

Objective:To study the effects of Isoflurane on the learning and memory function of Sprague-Dawley Rat's offspring during early gestation period.Method:Thirty SD rats, pregnant for 5—7 days, were randomly divided into three groups—the Isoflurane 1 group(group Isol),Isoflurane 2 group(group Iso2)and Control group(group C). In the group Isol, inhaled 1.4% Isoflurane for 4 hours, in the group Iso 2, inhaled 1.4% Isoflurane for 8 hours, and the group C,only inhaled mixed gas containing 40% oxygen for 8 hours. After the pregnant rats deliveries, offspring were divided into 20 days subgroup and 30 days subgroup. The learning and memory function of offspring were tested by Morris water maze test. Offspring were killed at 24 h after last test and the brains were immediately removed for determination of the expression of the NR2B protein (using immuno-histochemistry) and NR2B, HGN mRNA (using RT-PCR) and in the hippocampus.Result:During the Morris water maze test, there was no significant difference in escape latency of the offspring in 3 groups. Among Group C, group Isol,and group Iso2, their offspring 20 days postnatal, the number of through platform respectively were 2.40±0.69,2.31±0.50,2.27±0.28, the time staying in platform quadrant respectively were 31.76±8.8,29.16±5.69,31.46±9.04,no significant difference.30 days postnatal, the number of through platform among 3 groups respectively were 2.29±0.35,2.34±0.71,2.16±0.54, the time staying in platform quadrant respectively were 30.75±9.85,31.52±6.65,28.47±8.71,there was no significant difference. The NR2B protein appeared in all offspring, the expression of 20 days postnatal among 3 groups respectively were 143.20±2.28,146.60±2.07,139.40±4.51, the expression of 30 days postnatal respectively were 131.30±3.64,129.50±4.21,134.40±3.02, no significant difference. The mRNA of NR2B,HGN appeared in all the offspring of the three groups, the gray value of NR2B 20 days postnatal among 3 groups respectively were 0.6961±0.677,0.6943±0.604,0.6871±0.308, the gray value of HGN 20 days postnatal among three groups respectively were 0.6692±0.438,0.6790±0.373, 0.6793±0.397, three was no significant difference. The gray value of NR2B 30 days postnatal among Group C, group Isol,and group Iso2 respectively were 0.6637±0.277,0.6605±0.352,0.6597±0.389, the gray value of HGN among three groups respectively were 0.6997±0.412,0.7006±0.357,0.7014±0.307, three was no significant difference.Conclusion:Isoflurane shows no significant effects on the learning and memory function of the offspring in Sprague-Dawley Rats during early gestation period when administered under the way in this study.