The aim of the present research was to investigate the expression profiles of GnRH-R and neuropeptide Y (NPY) genes in brain and pituitary of Orange-spotted Grouper, Epinephelus coioides and also to understand the regulatory mechanism by administering different sex steroids. GnRH-R (TMD2 to TMD6) was partially involved cloned in this study. Tissue distribution analysis revealed a significant expression of GnRH-R in pituitary compared to others tissues. The expression of GnRH-R in brain and pituitary of groupers at different ages showed a significant increased during the fourth year, probably indicating the time of maturation. However, there was no significant difference in the expression of GnRH-R during different seasons. Treatment of two and three year old groupers with different sex steroids revealed an increase in the expression of GnRH-R in pituitary by E2 in both the age groups tested, while T could induce the expression of GnRH-R only in three year old groupers. The result, thus, indicates that the sensitivity of grouper to sex steroid is dependent on the age and the kind of steroid adminstered. In different sections of brain, the GnRH-R expression was in general lower in the group treated with E2 or T compared to the control group. The expression of the gene was more or less the same in two year and three year old control groups. This result may have been caused by suppression of GnRH-R expression in forebrain and midbrain after sex steroid injection. Administration of T induced a significant increase in the expression of GnRH-R in forebrain and midbrain, while E2 treatment did not have a similar effect. In hindbrain, the expression profile GnRH-R was not affected by sex steroid treatment in both two year and three year old groupers. The results suggest that sex steroids can only regulate the expression of GnRH-R in the forebrain and midbrain, probably due to the wide distribution of steroid¡¦s receptor in these regions. LHRH and pimozide injections to two year old groupers showed an increase in the expression of GnRH-R in pituitary after LHRH treatment while there was no stimulatory effect on other sections of the brain. In contrast, treating the fish with pimozide alone or pimozide together with LHRH did not stimulate GnRH-R expression in brain. Thus, the study suggests that LHRH can significantly increase the expression of GnRH-R in pituitary while dopamine has no stimulatory effect. Studies on NPY showed that the gene was distributed in different sections of brain especially in the forebrain but it was also present in gills, liver, intestine ¡K etc. The presence of NPY in gills, though less compared to that in brain, suggests that NPY might play an important role in osmosis regulation. The expression of NPY decreased with increase in age which may be due to the effect of other regulatory factors. Treatment of two and three year old groupers with different sex steroids did not effect the expression of NPY significantly in brain, which is different from other published reports. This may be due to the difference in the zoning of brain regions. In the present study, forebrain and midbrain were sampled together for analyses. The expression of NPY in brain did not change by treating the fish with LHRH or pimozide.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 125-162). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 125-162). Also available on the Internet.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 4 uppsatser.

The Hulver laboratory has recently found that the neuropeptide Y Y1 receptor (NPY Y1R) mRNA expression is elevated in skeletal muscle of obese humans (Hulver, unpublished). The goal of this research is to study the role of the NPY Y1R in skeletal muscle lipid metabolism. Rat L6, mouse C2C12, and human primary myotubes were incubated in 14C palmitate labeled fatty acid oxidation medium containing 80ng/mL, 250ng/mL, and 500ng/mL of NPY and for a three hour period. Experiments were repeated with the addition of 17mg/mL diprotin A to each NPY treatment. Fatty acid oxidation (FAO) and the percentage of lipids stored within the myotubes as diacylglyceride (DAG) and triaclyglyceride (TAG) were measured. Analyses were repeated in rat L6 and mouse C2C12 following a three hour incubation in 14C palmitate labeled fatty acid oxidation medium containing 1µg/mL, 10µg/mL, and 50µg/mL of the NPY Y1R ligand, [Leu31, Pro34] neuropeptide Y (Bachem, Torrance, CA). Incubation of human primary myotubes in NPY treatments with the addition of diprotin A significantly increased TAG accumulation (p< 0.05). Mouse C2C12 mytoube incubation in 500ng/mL NPY with diprotin A increased FAO (p 0.05). All other NPY and NPY Y1R ligand treatments in had no significant effect on FAO or the accumulation of TAG and DAG. / Master of Science

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.

Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains iv, 124 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 82-124).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1990. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 107-128).

Thesis (doctoral)--Lund University, 1994. / Added t.p. with thesis statement inserted.