| Home | E-Submission | Sitemap | Editorial Office |  
top_img
Journal of Korean Neurosurgical Society 1999;28(9): 1264-1271.
An Experimental Study of Effects of Nitric Oxide Synthase on Rat Anterior Pituitary Gland.
Ho Kook Lee, Do Yun Hwang, Youn Wha Kim, Yong Koo Park, Moon Ho Yang
1Department of Neurosurgery, College of Medicine, Hallym University, Seoul, Korea.
2Department of Pathology, College of Medicine, Kyung Hee University, Seoul, Korea.
ABSTRACT
OBJECTIVE
The nitric oxide synthases(NOS) are a group of isoenzymes that convert L-arginine to L-citrulline and generate nitric oxide(NO). The constitutive form of NOS is present in endothelium, adrenal gland, brain, and platelets, while the inducible form of NOS is present in macrophages, hepatocytes, vascular smooth muscle cell and endothelial cells. To determine whether NO has a role in anterior pituitary cell function, immunohistochemistry and molecular techniques were used to study NOS expression in rat pituitary gland. MATERIALS AND METHODS: We treated the rats with two NOS inhibitors: N-mono-methyl amine(NMMA), which is an inhibitor of NOS activity, and aminoguanidine, which a selective inhibitor of the inducible NOS isoform and two NO donors; sodium nitroprusside(SNP), s-nitro-acetyl-penicillamine(SNAP) as well as L-arginine. Rat growth hormone was measured in the serum using radioimmunoassay and NOS producing cells in the anterior lobe of the pituitary was detected by immunohistochemical stains. Also mRNA was extracted from the pituitary and performed RT-PCR using inducible NOS primer.
RESULTS
Serum growth hormone levels were increased significantly by administration of NOS inhibitors, such as NMMA and aminoguanidine. Immunohistochemical stains for neuronal and inducible NOS showed strong positivity in the folliculostellate cells and weak positivity in the anterior pituitary cells in the control and various experimental groups. RT-PCR in inducible NOS showed more brighter band in the 222 base pairs in the aminoguanidine treated group than normal control group.
CONCLUSION
These data suggest that pituitary NOS may play a pivotal role in the control of growth hormone secretion.
Key Words: Nitric oxide synthase; Pituitary; Immunohistochemistry; RT-PCR; Rat
Editorial Office
1F, 18, Heolleung-ro 569-gil, Gangnam-gu, Seoul, Republic of Korea
TEL: +82-2-525-7552   FAX: +82-2-525-7554   E-mail: kns61@neurosurgery.or.kr
About |  Browse Articles |  Current Issue |  For Authors and Reviewers
Copyright © Korean Neurosurgical Society.                 Developed in M2PI
Close layer