IMMUNOGOLD DETECTION OF 2 NEUROHORMONES - THE LOCUST OVARY MATURING PARSIN AND NEUROPARSIN

The cellular localization of two neurohormones of the locust pars inte rcerebralis-corpora cardiaca system: the ovary ma turing parsin and ne uroparsin, was investigated using electron microscopic immunocytochemi stry (post-embedding immunogold labelling). The ovary maturing parsin and neuroparsin containing cells were first identified in semithin sec tions treated by combined histochemical- and immunostaining. The neuro parsin cells were paraldehyde fuchsin positive (A-type cells) and the ovary maturing parsin cells were paraldehyde fuchsin negative when sem ithin sections were stained with paraldehyde fuchsin and immunostained with anti-ovary maturing parsin serum. The ovary maturing parsin and neuroparsin producing cells were identified on immunogold labelled ult rathin sections adjacent to double stained semithin sections. Ovary ma turing parsin cells have larger more numerous vesicles of greater elec tron density than neuroparsin cells. The neuroparsin cells contained m ore lysosomal structures than the ovary maturing parsin cells suggesti ng different neurosecretory dynamics. Thus, immunogold labelling with antisera specific for each neurohormone demonstrates the individual na ture of these two neurosecretory cells in the pars intercerebralis of the Locust.