[Effects of ethanol intake by the mother rat on learning ability and behavior of offspring rats].

Abstract

The effects of ethanol intake by the mother rat were studied in five groups of Fischer strain rats; we observed learning ability and behavior of offspring rats using a maze with eight radial arms. I The ethanol free-intake groups (F-) were given a 10% aqueous solution of ethanol, classified by length of ethanol exposure. The mother rats were exposed to ethanol from a young age. The offspring were classified as follows: A. to the delivery (F-DEL), B. to the lactation period (F-NURS), C. to the lactation period, and after weaning, the offspring was continuously exposed to the maze experiment (F-CON). II The ethanol compulsory-intake group (P-DEL) was given a 20% aqueous solution of ethanol, 2 ml/100 g b.w., for the first time on the first day of pregnancy. The solution was given orally once a day through gestation. III The control group was not exposed to ethanol. Radial arm maze observations were made on offspring rats during a total of 30 trials, and we made the following findings: 1) The number of trials required for fulfilling learning criterion was significantly large in F-DEL and F-NURS male rats groups relative to the controls; that is, F-DEL and F-NURS were slow in learning. The number of rats which did not fulfill the learning criterion was significantly large in F-DEL and F-NURS male rats groups, relative to the controls. 2) In all groups running time was shortened with training time, it was result of acclimation to the device and of practice to catch and eating feed. In female rats of the F-DEL and F-NURS groups, running time was not shortened with the training, relative to the control. 3) The behavior of the rats in the F-CON group differed from those in the other groups: The number of well-performed trials was significantly large in F-CON rats group relative to control. They seemed to lack carefulness, and the number of times they failed to eat the feeds even though they succeeded in selecting the correct arm, was significantly large in F-CON female rats group, relative to the controls, in the final 10 trials. Their motion was abrupt and they ran at extraordinarily high speeds. 4) The number of trials required for fulfilling learning criterion was significantly large in the P-DEL rats relative to the controls.(ABSTRACT TRUNCATED AT 400 WORDS)