Histochemical observations on the juxtanuclear complex of organelles in the hamster oocyte.

The hamster ovarian oocyte surrounded by 2-3 layers of granulosa cells develops a large juxtanuclear complex of organelles, consisting of basophilic substance, mitochondria and some lipid inclusion bodies. The basophilic substance staining for RNA, protein and some diffuse lipoprotein forms the material with which the granular mitochondria, composed of protein and phospholipid, apparently multiply. The lipid inclusion bodies consist of phospholipids. The results of this histochemical investigation have been correlated with those of ultrastructural studies on the hamster oocyte. The paranuclear complex of organelles described in this paper has also been compared and contrasted with that seen in the primordial oocyte of hamster, as reported in the previous publication. The functional significance of juxtanuclear entities has been discussed in relation to the multiplication of organelles to be accumulated during oocyte growth.     

Studies on the neurosecretory system and retrocerebral endocrine glands of Nezara viridula Linn. (Heteroptera: Pentatomidae)

The neurosecretory system and retrocerebral endocrine glands of Nezara viridula Linn. have been described on the basis of in situ preparations and histological sections employing the paraldehyde fuchsin (PF) and performic acid-victoria blue (PAVB) techniques. In the brain of N. viridula, there are two medial groups–each consisting of five neurosecretory cells which belong to A-type. The lateral neurosecretory cells are absent. The axons of the two groups of medial neurosecretory cells (MNC) compose the two bundles of neurosecretory pathways (NSP) that decussate in the anterodorsal part of the protocerebrum. The two pathways, after the cross-over, run deep into the protocerebrum and deutocerebrum and emerge as NCC-I from the tritocerebrum. The nervi corporis cardiaci-I (NCC-I) of each side which are heavily loaded with NSM terminate in the aorta wall. Thus, the neurosecretory material (NSM), elaborated in the medial neurosecretory cells of the brain, is stored in the aortic wall and nervi corporis cardiaci-I (NCC-I). The NCC-II are very short nerves that originate from the tritocerebrum and terminate in the corpora cardiaca (CC) of their side. Below the aorta, but dorsal to the oesophagus, lie two oval or spherical corpora cardiaca. A corpus allatum (CA) lies posterior to the corpora cardiaca (CC). The corpora cardiaca do not contain NSM; only the intrinsic secretion of their cells has been occasionally observed which stains orange or green with PF staining method. The corpus allatum sometimes exhibits PF positive granules of cerebral origin. A new connection between the corpus allatum and aorta has been recorded. The suboesophageal ganglion contains two neurosecretory cells of A-type which, in structure and staining behaviour, are similar to the medial neurosecretory cells of the brain. The course and termination of axons of suboesophageal ganglion neurosecretory cells, and the storage organ for the secretion of these cells have been reported. It is suggested that the aortic wall and NCC-I axons function as neurohaemal organ for cerebral and suboesophageal secretions.     

Histochemical observations on the apocrine glands of the scrotal skin of the cat and dog

Enzyme and carbohydrate histochemical methods were used to study the secretory activity of the apocrine glands of the scrotal skin of the cat and dog. The typical activity spectra of the different oxidative and hydrolytic enzymes investigated indicated high metabolic rates within the secretory cells. The carbohydrate histochemical differentiation revealed mostly neutral and partly acidic glycoproteins, with only small amounts of sialic acid, in the secretory cells and the luminal secretion of the glands. The PO-lectin-DAB procedures applied demonstrated that the following saccharide residues were dominant within the neutral glycoproteins present: alpha-D-glucose, alpha-D-mannose, beta-D-galactose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine.     

Evolution of endocrine glands and neuroendocrine systems: the "humoral code"

Origin of complex neuroendocrine systems in evolution seems to be based on the signalling functions of molecules produced by separate groups of cells and glands, and each of these molecules "is coding" some distinct conditions of internal milieu and environment for the cell and the whole organism. Use of such "coding" molecules for the integration of the separate glands in the neuroendocrine systems permits to guaranty supply of vital substances to the organism regardless of external and internal disrupting circumstances, and to retain ability to alter the levels of the hormones produced by these systems in accordance with changes in internal milieu and environment.     

Histochemical observations on the mycetomes of Pyrilla perpusilla Walker.

Histochemical studies of mycetomes and mycetocytes of Pyrilla perpusilla show PAS positive material, what can suggest the presence of glycogen. The mycetocytes failed to stain with alcian blue and methyl green pyronin "Y" indicating the absence of mucopolysaccharides and RNA respectively. The mycetocytes show positive congo red. Millon and Mercury bromophenophenol blue staining thereby proving that they contain glycoprotein, tyrosine and proteins. Positive reaction with Sudan black may show the presence of lipids and lipoproteins.     

Histochemical observations on uptake of L-dopa into endocrine cells of the rat pituitary gland during the postnatal development

The uptake of L-dopa into the cells of the adenohypophysis of the rat was studied during the postnatal development and at adult age using the formaldehyde-induced fluorescence method (FIF). The cells taking up L-dopa were classified by Alcian blue-PAS-Orange G staining. The correlation between the cells taking up L-dopa and those containing tryptophyl-peptide was estimated during the postnatal period and in adult rats. The cells containing tryptophyl-peptide were demonstrated using fluorescence induced by treatment with combined formaldehyde and acetyl chloride vapour. The following observations were made: 1) Great majority of the cells taking up L-dopa did not contain tryptophyl-peptide. Thus the accumulation of L-dopa into the cells of pars distalis is not due to accumulation of L-dopa into the cells by the same transport mechanism as the amino acids for tryptophyl-peptide. 2) Of the cells taking up L-dopa in the adult rats 96% were chromophobes, 2.0% acidophilic cells (somatotrophs and cells producing prolactin), 0.9% R-mucoid cells (corticotrophs), and 1.2% S1- and S2-mucoid cells (gonadotrophs and thyrotrophs). At 10 and 25 days' age the relative numbers of the cells taking up L-dopa were about the same. 3) Pretreatment with nialamide caused only a slight increase in the number of the cells taking up L-dopa. The decrease in the number of the cells uptaking L-dopa of the pars distalis, which takes place after 5 weeks' age is thus not caused by the increased MAO-activity. 4) Strongly chromophilic cells did not take up L-dopa. At the light of our results it seems evident that L-dopa is taken up by the chromophobic cells when these differentiate into chromophilic cells. The accumulation of L-dopa may be a sign of an active transport of amino acids into the cells. The accumulation of L-dopa into the chromophobic stellate and follicular cells may reflect their metabolic activity. These cells probably have an important role in the production of the hormones of the pars distalis.