Influence Of Oral Intake Of Milk, Glucose And Acrylamide On The Growth And Follicle Development In Weaned Rats

In humans, ingested lactose is converted to glucose and galactose by the intestinal enzyme called lactase. The further metabolism of galactose to UDP-glucose involves three major enzymes, galactokinase, galactose-1-phosphate uridyltransferase (GALT), and UDP-galactose-4-epimerase. A number of epidemiologic studies have examined the relationship between intake of lactose from dairy products and ovarian cancer but, to date, the data remain conflicting.It is understood that a link exists between the availability of metabolic fuels and reproductive function in mammals. As reproduction is metabolically costly, when food becomes scarce, puberty is delayed as a way to preserve valuable energy reserves for more important life processes. The body monitors energy availability, and uses this information to determine if there is enough to initiate the onset of puberty and normal reproductive function. The details of the mechanism controlling this pathway or the exact nature of the metabolic signal still remain unclear.The obesity of adolescent is a very serious problem now. Along with the obesity puberty has onset earlier. Reserchers presume the most possible reason is the nutrition that adolescent intake is disproportion, function in many animal models provides evidence that the earlier onset of pubertal development. Wether dairy products and glucose can onset puberty earlier or postpone is a very hot discussion.Therefore, I choose weaned Sprague and Dawley (SD) rats as animal models to find the relationship among milk, glucose and the puberty of female rats. It is important to understand whether this increased intake of milk and sugar would affect the growth of the kid during adolescence. The current experiment examined that the effects of milk and sugar intake frequently on puberty in immature female rats. The weaned rats drank milk and sugar daily instead of tip water for 40 days. The experimental animals were examined daily with the vaginal open day and checked smear everyday afterwards, weighted body weight every week during experimental period. In the end of experiment, weights of the ovary and uterus, levels of blood sugar and morphometric of ovaries were examined.The results showed that the vaginal open day of treated group is earlier than that of the control group, which might imply that the puberty arrived earlier by drinking milk and sugar. In addition, the ratio of ovarian weight to body weight was increased with milk and sugar drinking. Further, numbers of developmental follicles, atretic follicles and corpora luteal were increased in the treatment of milk compared with the control group, while, only the number of corpora luteal in sugar group was increased compared with the control group. Together, the results of our current experiment suggested that drinking milk and/or sugar has potential effects on puberty of weaned rats.Acrylamide is a common kind of chemical and the toxicity of acrylamide has been investigated well since the 80s of last century. In 2002, We always use Acrylamide to synthesize polyacrylamide.The toxicity of Acrylamide is generally acknowledged, especially the nurotoxicity. But this kind of reserch in the ovary is very limited. In experiment two, SD rats, which are 22 days old and just weaned, were given acrylamide water-soluble. One group was intake 5 mg per kilogram body weight, the other intake 10mg per kilogram body weight. Then record the vginal open day, vginal test result, gain of body weight very week, the ratio of uterus and ovary to body weight, gather all ovaries to obersve the follicular development. The result demonstrated that control group and the experimental group have significant differences in body gain, the ratio of body gain and vginal open day (p<0.05), but similar in two experimental groups. Control group and 10mg experimental group are different significantly in uterus, heart, liver, lung weight, but quiet to 5mg experimental group. There are significant differences in total follicular number, primary follicular number and secondary follicular number between control group and 10mg expeirimental group. My study suggests that acrylamide can impact the growth and follicular development in the female rat.