An Enzyme Histochemical-study Of The Distribution Of Nitric Oxide Synthase (NOS) During Gametogenesis Of Orthoptera Insects

As a message and effect molecule, nitric oxide (NO) was not studied widely until 1990s. The remarkable achievements have been attained in higher mammal. Through more ten year-study, we found that NO play an important role in circulatory system, nervous system, digestive system, immunitory system, reproductive system, etc. The actions of NO in reproductive system were gradually noticed, and turned into a new research area. As for the studies of NO in invertebrates, we have attained some achievements too in recent years. We studied here the distribution of NO during the gametogenesis of five Orthoptera insects by enzyme histochemical method.Firstly using enzyme histochemical method of NADPH diaphorase, we studied the distribution of nitric oxide synthase (NOS) during the gametogenesis of five Orthoptera insects: Oxya chinesis (Thunberg), Acrida cinerea Thunberg, Atractomorpha lata (Motsh.), Teleogryllus emma (Ohmachi & Matsuura), Phamropter gracilis Burmeister. The results show that NOS positive reaction occurred in cytoplasm of permatogenic cells in different stages during the gametogensis of five insects, while negative reaction occurred in matured sperms. The expression pattern of positive products has changed in different species. NOS positive products usually distributed in the spermatogenous cells and primary spermatocytes of Oxya chinesis, Atractomorpha lata and Acrida cinerea .In the secondary spermatocytes of Oxya chinesis and Acrida cinerea NOS positive products are have not regularity in distribution. For example as Atractonorph lata, NOS positive products concentrated at one polar of the secondary spermatocytes. In the spermoblasts of these five insects NOS positive products distributed at the long-tail region of spermated.The distribution of NOS during oogenesis of five insects all follow a similar rule, such as NOS positive reaction, is obvious in the immature oocyte, With the formation of yolk granules, positive products diminish gradually until the deposit of yolk granules completely finished. During the development of the follicle cells, the time of NOS positive reaction appear to a difference in those five species. The results demonstratethat NO may participate in the process of those insect gametogenesis.The spermatheca is used to store sperm in female insects. The mechanism of storing sperm is tight correlative with the structure of the spermatheca. In this paper, using conventional paraffin section technique, we studied the histology of spermatheca of Phaneropter gracilis under the optical microscope. The results show that the spermatheca is an ellipse sacculated structure. From outer to inner, the spermatheca contains peritoneal membrane, connective tissue, muscle layer, glandular cell layer and ground membrane. Those results will provide some morphologic evidence for the mechanism of sperm storage in spermatheca of insects.The central nervous system of Teleogyllus emma (Ohmachi and Matsuura) consists of brain, suboesophageal ganglion and ventral nerve-cord. There are obvious differences among procerebrum, deutocerebrum and tritocerebrum. Ventral nerve-cord consists of three pairs of thoracic ganglia, five pairs of abdomind ganglia and connectives between ganglia. The structure characters of the brain and the ganglia are similar to each other. Froming outside to inside are Nerve sheath, Neurocyte and Neuropile. The neuropile of procerebrum consisting of a pair of corpora pedunculata, pars intercerabralis, corpuscentrale and a pair of corpora ventralis is more complex than other ganglia.