Effects of aroclor 1254 on the expression of the KAP3 gene and reproductive function in rats

Article

<< Previous

Next >>

Contents Vol 19(4)

doi:10.1071/RD06117

Effects of aroclor 1254 on the expression of the KAP3 gene and reproductive function in rats

Chae Kwan Lee ^A, Han Seung Kang ^B, Ju Ran Kim ^C, Byung Ju Lee ^D, Jong Tae Lee ^A, Jeong Ho Kim ^A, Dae Hwan Kim ^A, Chang Hee Lee ^A, Jin Hong Ahn ^A, Chae Un Lee ^A, Seong Jin Yu ^C, Sung Goo Kang ^C ^E

^A Institute of Industrial Medicine, Department of Occupational and Environmental Medicine, Busan Paik Hospital, Inje University, Busan 614-735, South Korea.
^B Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 133-791, South Korea.
^C School of Biotechnology and Biomedical Sciences, Inje University, Kimhae 621-749, South Korea.
^D Department of Biological Sciences, College of Natural Sciences, Ulsan University, Ulsan 680-749, South Korea.
^E Corresponding author. Email: biosgkan@inje.ac.kr





	PDF (313 KB) $25



	Export Citation

Print

Reproduction, Fertility and Development 19(4) 539–547 http://dx.doi.org/10.1071/RD06117
Submitted: 8 September 2006 Accepted: 6 March 2007 Published online: 3 May 2007

Abstract

The present study investigated the effects of aroclor 1254 (A1254) on the expression of the kinesin superfamily associated protein 3 (KAP3) gene in F₁ rat brain during brain sexual differentiation and puberty. In addition, the effects of A1254 on reproductive function were examined. The KAP3 gene is involved in the neurogenesis and synaptogenesis of sexual differentiation in rats and also during puberty. In the present study, pregnant Sprague–Dawley rats each received a daily dose of A1254 (0, 10, 50 mg kg^–1) dissolved in 1.0 mL corn oil by gavage, from gestational Day (GD) 8 to postnatal Day (PD) 21. The mRNA levels of the KAP3 gene in hypothalamic tissues were analysed by northern blot hybridisation during the critical periods of brain sexual differentiation (GD18 and PD5) and puberty (PD28). Variables affecting reproduction in F₁ female rats, such as vaginal opening (VO), vaginal oestrus (VE) and oestrous cyclicity, were recorded. Depending on the sex and A1254 exposure (control or 50 mg kg^–1 day^–1), F₁ rats were divided into three mating groups, namely control male–control female, control male–A1254-treated female and A1254-treated male–control female. During the critical periods of brain sexual differentiation (GD18, PD5) and puberty (PD28), KAP3 mRNA levels were significantly reduced in A1254-treated fetal and pubertal rat brains relative to those of control groups. In A1254-treated F₁ female rats, VO and VE were delayed, the percentage of irregular oestrous cycles was increased and the duration of the oestrous cycle was extended in a dose-dependent manner compared with control groups. Treatment with a high dose of A1254 significantly impaired the reproductive function of both male and female F₁ rats, including mating and pregnancy indices and the number of live fetuses. These data suggest that A1254 disrupts transcriptional regulation of the KAP3 gene in fetal and pubertal rat brains and that these effects may be related to A1254-induced abnormal brain sexual differentiation and lowered reproductive function in F₁ rats.

Keywords: fetoneonatal oestrogen-binding protein, kinesin superfamily protein, oestrogen, testosterone.