Changes in the pituitary and serum gonadotropin levels of Cranoglanis bouderius were studied at different stages of ovarian development. Based on African catfish gonadotropin (cfGTH) and its anti-serum (Racf), heterol...Changes in the pituitary and serum gonadotropin levels of Cranoglanis bouderius were studied at different stages of ovarian development. Based on African catfish gonadotropin (cfGTH) and its anti-serum (Racf), heterologous radio-immunoassay (RIA) for the gonadotropin (GTH) of Cranoglanis bouderius was developed. The pituitary GTH contents at the late development stage were significantly higher than that at the mature, ovulation or regressed stages, while serum GTH levels at maturation and ovulation were significantly higher than that at late development and regressed stages. Injection of gonadotropin-releasing hormone analogue (GnRH-A) stimulated GTH secretion. Domperidone (DOM) had no effect on the basal serum GTH level. Injection of GnRH-A and DOM significantly enhanced the GTH levels stimulated by GnRH-A alone. These results indicate that GTH release in Cranoglanis bouderius is under the dual regulation of gonadotropin releasing hormone (GnRH) and dopamine (DA) from the hypothalamus, but DA can only inhibit GTH release induced by GnRH and not basal GTH release.展开更多
[ Objective] To locate gonadotropin-releasing hormone （GnRH） in pituitary of Guangxi swamp buffaloes and to provide a theoretical ba- sis for cloning and sequence analysis of GnRH receptor gene. [ Method] GnRH in pi...[ Objective] To locate gonadotropin-releasing hormone （GnRH） in pituitary of Guangxi swamp buffaloes and to provide a theoretical ba- sis for cloning and sequence analysis of GnRH receptor gene. [ Method] GnRH in pituitary were immunohistochemically stained by avidin biotin complex method. The GnRH expression was analyzed with image system. The GnRH receptor gene was amplified by real-time PCR. [ Result] Many GnRH positive cells were detected in pars distalis of adenohypophysis. GnRH were distributed in cytoplasm but not in nuclei. No positive sig- nal was observed in neurohypophysis. In addition, the GnRH receptor gene, 920 bp in size, was amplified. [ Conclusion] A large number of GnRH and GnRH receptor were found in pars distalis of adenohypophysis, which indicates that anterior pituitary is an important tissue for functions of hypo- thalamus-pituitary-gonadal axis and other endocrine axes.展开更多
文摘Changes in the pituitary and serum gonadotropin levels of Cranoglanis bouderius were studied at different stages of ovarian development. Based on African catfish gonadotropin (cfGTH) and its anti-serum (Racf), heterologous radio-immunoassay (RIA) for the gonadotropin (GTH) of Cranoglanis bouderius was developed. The pituitary GTH contents at the late development stage were significantly higher than that at the mature, ovulation or regressed stages, while serum GTH levels at maturation and ovulation were significantly higher than that at late development and regressed stages. Injection of gonadotropin-releasing hormone analogue (GnRH-A) stimulated GTH secretion. Domperidone (DOM) had no effect on the basal serum GTH level. Injection of GnRH-A and DOM significantly enhanced the GTH levels stimulated by GnRH-A alone. These results indicate that GTH release in Cranoglanis bouderius is under the dual regulation of gonadotropin releasing hormone (GnRH) and dopamine (DA) from the hypothalamus, but DA can only inhibit GTH release induced by GnRH and not basal GTH release.
基金supported by the grants from Research and Innovation Project for Master Degree Candidates(105930903014)Guangxi Natural Science Foundation(06400150832043 and 0991042+3 种基金Guangxi Science and Technology Department)Research Foundation of Guangxi Education Department(200709LX075Guangxi Education and Research)Guangxi Large-scale Instrument Collaboration and Sharing Network Program
文摘[ Objective] To locate gonadotropin-releasing hormone （GnRH） in pituitary of Guangxi swamp buffaloes and to provide a theoretical ba- sis for cloning and sequence analysis of GnRH receptor gene. [ Method] GnRH in pituitary were immunohistochemically stained by avidin biotin complex method. The GnRH expression was analyzed with image system. The GnRH receptor gene was amplified by real-time PCR. [ Result] Many GnRH positive cells were detected in pars distalis of adenohypophysis. GnRH were distributed in cytoplasm but not in nuclei. No positive sig- nal was observed in neurohypophysis. In addition, the GnRH receptor gene, 920 bp in size, was amplified. [ Conclusion] A large number of GnRH and GnRH receptor were found in pars distalis of adenohypophysis, which indicates that anterior pituitary is an important tissue for functions of hypo- thalamus-pituitary-gonadal axis and other endocrine axes.
