[Application of lysosomal detection in marine pollution monitoring: research progress].

Lysosome is an important organelle existing in eukaryotic cells. With the development of the study on the structure and function of lysosome in recent years, lysosome is considered as a target of toxic substances on subcellular level, and has been widely applied abroad in marine pollution monitoring. This paper summarized the biological characteristics of lysosomal marker enzyme, lysosome-autophagy system, and lysosomal membrane, and introduced the principles and methods of applying lysosomal detection in marine pollution monitoring. Bivalve shellfish digestive gland and fish liver are the most sensitive organs for lysosomal detection. By adopting the lysosomal detection techniques such as lysosomal membrane stability (LMS) test, neutral red retention time (NRRT) assay, morphological measurement (MM) of lysosome, immunohistochemical (Ih) assay of lysosomal marker enzyme, and electron microscopy (EM), the status of marine pollution can be evaluated. It was suggested that the lysosome could be used as a biomarker for monitoring marine environmental pollution. The advantages and disadvantages of lysosomal detection and some problems worthy of attention were analyzed, and the application prospects of lysosomal detection were discussed.

[Localization of the estrogen receptor alpha and beta-subtype in the nervous system, Hatschek's pit and gonads of amphioxus, Branchiostoma belcheri].

Immunocytochemical localization were investigated in the nervous system, wheel organ, Hatschek's pit and gonads of amphioxus using polyclonal antibodies against estrogen receptor-alpha and beta. The results revealed that ER-alpha and beta protein distributed in the above regions in larvae and adult at different developmental stages of both sexes. A major ER-alpha were expressed within nucleus of nerve cells, a few expressed in the cytoplasm and process as well as fiber of nerve cells in the forebrain, midbrain, hindbrain and nerve tube, while ER-beta were detected in the cytoplasm or on the cellular membrane, a few were within nucleus. ER-alpha immunopositive material distributed mainly in the nucleus of epithelial cells in the second layer of Hatschek's pit, a few were in the cytoplasm of upper layer epithelial cells, while ER-beta distributed in the nucleus of upper layer. In gonads, ER-alpha were distributed in the cytoplasm and nucleolus of oogonia and oocyte of small growth stage, germinal vesivle(nucleus) showed immunonegative reaction. In the large growth stage, strong immunopositive reaction were showed in nuclear membrane and nucleolus of oocyte, and within nucleus of mature egg cell in the mature stage. ER-beta immunopositive material distributed in the cytoplasm of oogonia and early oocytes as well as egg envelope of mature egg cell, the germinal vesicle showed immunonegative reaction. In testis, both ER subtype were localized in the cytoplasm of spermatogonia, primary and second spermatocyte as well as Sertoli cell, and within nucleus of spermatid cell, while spermatozoa showed immunonegative reaction. On the other hand, the results of double staining revealed that ER-alpha and beta numerously coexisted in a same cell, and fewly expressed in different cells in above regions. It is found for the first time that both estrogen receptor subtype, which mediated the regulate role of estrogen to neuroendocrine tissues in amphioxus, distributed extensively in amphiuoxus. The different localization of ER-alpha and beta receptor in the target cells suggests that the mediating estrogen signal line and the mechanism of gene transcription may be different.

[Distribution of neuropeptide Y-like and beta-endorphin-like immunoreactivity in the nervous system and Hatschek's pit of amphioxus, Branchiostoma belcheri].

Using immunohischemical method, we have localized for the first time in the amphioxus, Branchiostoma belcheri, neuropeptide Y (NPY)-like and beta-endorphin (beta-Ep)-like immunoreactivity in nervous system and Hatschek's pit. NPY-immunoreactive (-ir) perikarya appeared in the front and middle areas of the telencephalon and midbrain, as well as in the hindbrain. Dense plexuses of NPY-ir fibers coursed with NPY-ir neurons and formed fine networks. NPY-ir perikarya and fibers were observed in the dorsal and middle areas of spinal cord. Beta-Ep-like immunoreactive perikarya and fibers were located in the front and middle areas of the midbrain, as well as in the spinal cord, but not in the telencephalon and hindbrain. The regions showing beta-Ep immunoreactivity were less than that of NPY. NPY-like and beta-Ep-like immunoreactivity were also found in the Hatschek's pit of amphioxus. These results suggest that NPY and beta-Ep, as an neurotransmitter as in fish, may be involved in the regulation of Hatschek's pit gonadotrophic cells secretory activity in amphioxus, and provide a new morphological evidence for the close relationship between brain and Hatschek's pit in amphioxus.