Histochemical and Immunological Localigation of Nitric Oxide Synthase in Insect Brain and Retrocerebral Complex

• Main Authors: Chih-Yung Lin, 林志勇
• Other Authors: Ann-Shyn Chiang
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/64756702237910718657

碩士 === 國立清華大學 === 生命科學研究所 === 84 === It is now well established that nitric oxide (NO) is a major inter- and intracellular neurotransmitter in the brain and peripheral nervous system. NO is formed from L-arginine by the enzyme NO synthase (NOS). Remarkable conservation of neuronal NOS has been noted between verterbrates and inverterbrates. Recently, NOS has also been identified in discrete subpopulations of anterior pituitary cells and NO may exert an inhibitory effect on release of luteinizing hormone and growth hormone. While there are ev idence showing production of NO from insect nervous system, nothing is known about the cellular localization of NOS in insect endocrine system. Insect corpora allate (CA) produce juvenile hormone (JH) and are considered the analogue of the anterior pituitary gland of verterbrates. While the CA have been shown to be the release site for several neuropeptides from brain neurosecretory cells, it is generally believed that JH is the only product synthesized and released from corpus allatum cells involving in the regulation of insect growth, metamorphosis and reproduction. We have now demonstrated that all corpus allatum cells contain a constitutive NOS which synthesize and release NO. The NOS is calcium dependent and inhibited by brain neurons terminating in the CA.