Salivary glands of the cat: A histochemical study

Synopsis The submandibular, sublingual and parotid glands of the cat have been studied. Mucosubstance histochemistry demonstrated acidic mucosubstances with varying properties in the acini. Thiamine pyrophosphatase and nucleoside diphosphatase reaction products were seen with a Golgi-like appearance in acinar cells. Granules of acid phosphatase, -glucuronidase and E600-resistant esterase reaction products, presumably representing lysosomal enzyme activities, were seen in acinar and ductal cells. Diffuse acid phosphatase and -glucuronidase reaction products were seen in central cells of the submandibular acini, and diffuse non-specific esterase reaction product was seen in acinar and ductal cells. Arylamidase reaction product was associated with some acinar cells. Reaction product from a peroxidase technique was seen in demilunar cells of the submandibular acini, in parts of the sublingual acini, in parotid acini, and in ductal cells. Cytochrome oxidase and succinate dehydrogenase reaction products were seen most strongly in striated ducts, whereas NADH- and NADPH-diaphorase reaction products were seen at a high level throughout the ducts.     

Morphological and functional study of the GH-immunoreactive adenohypophyseal cells in ovariectomized rats

Summary In view of the existence of a different secretion pattern of growth hormone (GH) between male and female rats, the aim of the present study was to analyse the role played by ovarian steroid hormones in the modulation of such secretion. To do so, postpuberal female rats were ovariectomized and killed at 30 days after the operation. The basal serum levels of growth hormone, together with cell area, cytoplasmic area and nuclear area of the hypophyseal somatotropic cells of normal and ovariectomized rats were compared. The results obtained show that ovariectomy induces a significant decrease (p<0.05) in the basal serum levels of GH, accompanied by an increase in cellular and cytoplasmic areas, with no significant differences in nuclear area. Overiectomy was also accompanied by an increase in reaction intensity and the number of GH-immunoreactive cells (p<0.01). These findings point to the shift towards a masculine secretory and morphological pattern following ovariectomy and supports the hypothesis that ovarian steroids intervene in the establishment of a different pattern in females compared to males.     

An immunohistochemical study of adenohypophyseal cells in the viviparous reptile Chalcides chalcides

The morphology of the hypophysis and the immunocharacteristics of the adenohypophyseal cells in the viviparous reptile Chalcides chalcides were studied by light microscopy, using conventional staining methods and an indirect antibody technique (ABC method), respectively. The general morphology of the C. chalcides hypophysis was comparable to that of other reptiles, showing three main regions: the pars distalis, the pars intermedia and the pars nervosa. The gland appeared as an elongated body in a cephalic-caudal direction and was almost completely enclosed in the sella turcica. For this reason, the hypophysis was studied in toto with the brain in decalcified specimens. The pars distalis accounted for most of the whole organ. The pars intermedia surrounded the pars nervosa as a goblet. The pars tuberalis was lacking.The immunohistochemical identification of the adenohypophyseal cells was performed using rabbit antisera against mammalian/synthetic hypophyseal hormones. Prolactin cells were clustered in small cellular cordons in the rostral pars distalis and in the medial pars distalis in both male and female specimens. Somatotropic cells were found in the caudal pars distalis. Corticotropic cells were observed in the medio-rostral pars distalis, as well as in the pars intermedia, where melanotropic cells were also present. Melanotropic cells were confined to the pars intermedia. Gonadotropic cells were mostly distributed in the ventral and lateral portions of the pars distalis, where they were found isolated or in small clusters. Thyrotropic cells were detected in the pars distalis with a distribution similar to that of the gonadotropic cells; however, atypically, they were also found in the pars intermedia. Therefore, the cytological characteristics of the adenohypophyseal cells appeared mostly conserved.     

Afferent projections to the locus coeruleus nucleus in the cat. Study by the horseradish peroxidase technic]

Using a retrograde tracer technique with horseradish peroxidase, we have revealed some afferent projections to the locus coeruleus complex from the contralateral pontine tegmentum, raphe nuclei, substantia nigra, nucleus of the solitory tract, dorsal motor nucleus of the vagus and other regions of the ponto-bulbar reticular formation as well as from hypothalamic and preoptic areas.     

Characterization by cytofluorometry of the different types of adenohypophyseal cells in the rat

The different antehypophysical cell types which synthetize and release somatotroph (GH), corticothroph (ACTH), gonadotroph (LH-FSH) and lactotroph (PRL) hormones were analysed. The experiments were performed on hypophyses from five groups of animals: adult males, 14 days-old female, adult females, gestating adult females and lactating adult females. The cells were analysed by immunofluorescence using flow cytometry. For each of the hormones studied, there was a characteristic spectral distribution of cells. The evolution of cell size and granular content with respect to sex and physiological state of each group was studied by the analysis of diffused light. Small, slightly granular cells represented 50% of the cell population in males and 14 day-old females but only 8% in gestating or lactating females. The study of the cell cycle showed the presence of dividing cells in the population of large, granular cells from gestating and from lactating females. No features of cell division were observed in the population of small, slightly granular cells. This study indicates the potential value of multiparametric analysis in the separation of pure sub-populations of antehypophysial cells.     

Enzyme histochemical studies of the general body surface apocrine glands in the domestic cat]

With enzyme histochemical methods, the distribution and the activities of various oxidative and hydrolytic enzymes in the apocrine glands of the general body surface of the domestic cat were investigated. The results obtained support the view that these glands are clearly active in function. On the whole, however, the relatively weak enzyme activities in the secretory portion of the glands point to only unimportant secretion production rates.     

Ultrastructural study of the Ca2+-dependent ATPase activity in rat adenohypophyseal cells

Ca-dependent ATPase activity in the rat anterior pituitary was demonstrated in 50-microns tissue slices of aldehyde-fixed tissue with the medium of Takano et al. (Cell Tissue Res. 243:91. 1986).--The outer surface of the plasma membrane of the parenchymal as well as the folliculo-stellate cells was lined with lead precipitate. The reaction deposit was particularly well localized in intercellular spaces both between two parenchymal cells, and between a parenchymal and a folliculo-stellate cell. A fine reaction deposit was also seen in the endoplasmic reticulum and Golgi apparatus of some parenchymal cells. Elimination of Ca2+ from the tissue and the substrate medium drastically reduced the amount of reaction product. If ATP was omitted or replaced by sodium beta-glycerophosphate, no reaction product was seen. Changing the Ca2+ concentration or addition of Mg2+ to the standard medium caused a decrease in reaction intensity. Substitution of Mg2+ for Ca2+ resulted, again in well-localized lead deposition which we attribute to the activity of another enzyme. We suggest that the activity we described in the membrane of glandular cells may correspond to the enzyme involved in the long-term regulation of intracellular Ca2+ level.     

Ultrastructural study of the Ca2+-dependent ATPase activity in rat adenohypophyseal cells

Summary Ca-dependent ATPase activity in the rat anterior pituitary was demonstrated in 50-m tissue slices of aldehyde-fixed tissue with the medium of Takano et al. (Cell Tissue Res. 243:91. 1986). — The outer surface of the plasma membrane of the parenchymal as well as the folliculo-stellate cells was lined with lead precipitate. The reaction deposit was particularly well localized in intercellular spaces both between two parenchymal cells, and between a parenchymal and a folliculo-stellate cell. A fine reaction deposit was also seen in the endoplasmic reticulum and Golgi apparatus of some parenchymal cells. Elimination of Ca²⁺ from the tissue and the substrate medium drastically reduced the amount of reaction product. If ATP was omitted or replaced by sodium -glycerophosphate, no reaction product was seen. Changing the Ca²⁺ concentration or addition of Mg²⁺ to the standard medium caused a decrease in reaction intensity. Substitution of Mg²⁺ for Ca²⁺ resulted again in well-localized lead deposition which we attribute to the activity of another enzyme. We suggest that the activity we described in the membrane of glandular cells may correspond to the enzyme involved in the long-term regulation of intracellular Ca²⁺ level.     

Autoradiographic and histochemical study of the intestinal epithelium of the Baltic lamprey]

The intestinal epithelium of the Baltic lamprey and its larva was studied. Glandular cells and absorbing cells simultaneously capable to synthesize polysaccharides were found histochemically in the composition of the epithelial layer. The cranial zone where glandular cells analogous to the cells of the pancreas were concentrated was revealed in the medial intestine of the larva. The rest of the intestine was devoid of specialized glandular cells. Using H3-thymidine as a precursor it was shown that in the cranial zone of the intestine the cambial cells were scattered diffusely throughout the whole epithelial layer and in other portions of the medial intestine the cambial zone was distinctly seen in the lateral portions of the intestine (the area of the fornix) where labelled nuclei were formed and mitoses took place. After injection of H3-thymidine poor incorporation of the isotope was found in the nuclei of solitary cells of some adult lampreys going to spawning. Uneven incorporation of S35-methyonine, used as a precursor, in the epithelium of the intestine and the liver of the adult lamprey was shown.     

Complex application of stains in the histochemical study of proteins]

The paper proposes a complex of methods for the histological study of protein which allosw revealing heterogeneity of its compostitions, determining the protein discharge and obtaining the data on the presence and distribution of a number of aminoacid residues. The schedule of the study includes reactions with dichlortriazine basic and acid stains (of both low and high affinity). The proposed schedule is convenient for detection and characterization of protein both in the structure, containing mainly proteins, and in the structures whose biopolymeres are represented mainly by carbohydrates.     

The distribution of noradrenergic nerves and small,intensely fluorescent (SIF) cells in the cat urinary bladder

Summary Fluorescence and electron microscopy have been used to study the distribution of noradrenergic nerves in the smooth muscle of the cat urinary bladder. Using the former technique, relatively few fluorescent noradrenergic nerves were observed in the body and fundus, while a rich plexus occurred adjacent to muscle cells of the bladder neck. The trigone could not be distinguished neuromorphologically from detrusor muscle in this region. Electron microscopy showed that the majority of noradrenergic terminals in the body and fundus were associated with presumptive cholinergic axons, while in the bladder neck noradrenergic terminals formed typical neuroeffector relationships with individual smooth muscle cells.Numerous ganglia occurred both in the adventitia and among the smooth muscle bundles, particularly in the bladder neck. The majority of the nerve cell bodies were non-fluorescent, although many contained bright orange autofluorescent granules, believed to be lysosomes. A small minority of ganglion cells were associated with fluorescent noradrenergic nerve terminals, thereby providing structural evidence for limited intraganglionic inhibition. In addition, occasional groups of small intensely fluorescent (SIF) cells were observed in some intramural ganglia and these were subsequently identified in the electron microscope. The possibility that these cells may provide a second inhibitory influence on bladder activity was considered.     

Neurohistological and histochemical characteristics of Loeschcke's zone of the cat medulla

Neuronal organization and transmitter profile of the chemosensitive area on the ventral medulla surface (zone L) were studied in the cat using neurohistological and histochemical techniques. Neurons of different shapes and sizes distributed through this area are concentrated mainly at the level of the medial hypoglossal nerve root, with their numbers gradually decreasing rostrally and caudally from this nerve. Only an insignificant proportion of zone L neurons are cholinergic and monoaminergic, while the remainder probably employ other biologically active substances as transmitters. Cholinergic and noncholinergic cholinoceptive neurons were found in zone L, as well as neurons sensitive to catecholamines and serotonin. It is postulated that the catecholaminergic, serotoninergic, and cholinergic fibers observed in zone L may be of local origin or may originate from other structures.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 18, No. 2, pp. 219–226, March–April, 1986.