Expression and significance of netrin–1 and its receptor UNC5C in precocious puberty female rat hypothalamus

Abstract

Objective

To study expressions of netrin–1 and its receptor UNC5C in female precocious puberty rat hypothalamus, and explore its effect on precocious puberty process.

Methods

Forty female one–week–old SD rats were randomly divided into four groups: experimental group A (precocious puberty early youth), experimental group B (precocious puberty medium youth), group A (normal pre–puberty), group B (normal early youth) with 10 rats in each group. Precocious puberty experimental rats were induced with Danazol and rats in control group were injected with saline. Uterus and ovaries were removed, specimens were weighed, uterus index and ovarian index were calculated, and amount of luteinizing hormone (LH) and follicle–stimulating hormone (FSH) were detected from the blood by ELISA. Real–time PCR was used to detect netrin–1 and its receptor UNC5C, as well as hypothalamic gonadotropin–releasing hormone (GnRH) mRNA expression in hypothalamus tissues; and then, a co–immunoprecipitation study of interactions between netrin–1 and its receptor UNC5C was carried out.

Results

Relative target gene expression levels of control group A, control group B, experimental group A, and experimental group B (with β –actin as an internal control for normalization) were as follows: Netrin–1: 3.5±0.9, 5.4±0.7, 4.9±1.0, 5.3±0.3; UNC5C: 0.8± 0.04, 1.7±0.2, 1.82±0.23, 1.58±0.4; GnRH: 1.2±0.3, 2.7±0.3, 2.4±0.7, 3.2±0.4.

Conclusions

LH and FSH concentrations, netrin–1 and its receptor expression are increased in precocious puberty animal models.