A histological study of cutaneous glands in the brown brocket deer

We examined the histological structure of 8 skin areas thought to contain cutaneous glands of potential importance in scent communication in 16 brown brocket deerMazama gouazoubira Fisher, 1814, using standard histological techniques. Frontal areas and preorbital sacs had scant glandular development. Sebaceous gland development was prominent in vestibular nasal glands and prepucial glands. Apocrine sudoriferous glands and sebaceous glands were well developed in tarsal glands, the caudal skin area and the interdigital glands of front and hind feet. The tail had a unique arrangement of apocrine sudoriferous glands. Anal glands had moderate glandular development, and metatarsal glands were absent. Several of these glandular areas may be important in the chemical communication among brocket deer.     

Characteristics of sialidase in the rat salivary glands

Using 4-methylumbelliferyl-N-acetylneuraminic acid (4MU-NeuAc) as substrate, we measured sialidase activity in the salivary glands and other organs of the rat. The pH optima of salivary gland sialidase were between 4.0 and 4.5, which were similar to those of the enzyme in the brain, liver and kidney. Among the salivary glands, the submandibular one showed the highest sialidase activity followed by the parotid and the sublingual glands. However, sialidase activity in these glands was lower when compared with the activity in the brain, liver and kidney. From the subcellular distribution study, salivary gland sialidase was found to be mainly localized in the lysosomes. The pH optima of the lysosomal sialidase of the salivary glands were between 4.0 and 4.5; and Km values for 4MU-NeuAc approximately 0.09 mmol/l. In the submandibular and parotid glands, a soluble sialidase with a different pH optimum (5.5) and Km value (0.25 mmol/l) was also detected.     

Morphological, histochemical and immunohistochemical characterization of secretory production of the ciliary glands in the porcine eyelid

In addition to performing general histology and cytology of the ciliary glands of the miniature pig, we studied the localization of glycoconjugates and beta-defensins in these glands with the use of carbohydrate histochemical and immunohistochemical methods. The secretory cells of the glands were equipped with non-homogeneous secretory granules, a well-developed Golgi apparatus and rough endoplasmic reticulum. The secretory epithelium and luminal secretion of the glands contained large amounts of neutral and acidic glycoconjugates with various saccharide residues (alpha-L-Fuc, beta-D-Gal, alpha-D-GalNAc and sialic acid). The sebaceous glands and tarsal glands also exhibited positive reactions to most of the histochemical methods. Additionally, the antimicrobial peptide group of beta-defensins was demonstrated to be products of the ciliary glands, as well as the sebaceous glands and tarsal glands. The results obtained are discussed with regard to the specific function of the ciliary glandular secretions. These secretory products may be related to the moistening and general protection of the skin surface of the eyelid and ocular surface.     

Spatial distribution and cell kinetics of the glands in the human esophageal mucosa

The glands in the human esophageal mucosa have been considered rudimentary, and have been poorly studied. Only recently, their role in the defense of the esophageal mucosa in gastroesophageal reflux disease has been put in evidence. In the present study, the presence of the different esophageal gland types was observed in 82 necropsy specimens. A precise topographical study was possible in 15 specimens. Cell proliferation parameters, namely DNA synthesis and mitotic index values in the squamous epithelium and in the esophageal glands were measured in 8 patients undergoing a surgical palliative esophagectomy, after in vivo labelling with bromodeoxyuridine. Upper mucosal, lower mucosal, and submucosal glands were observed in respectively 3.7%, 87% and 99% of the 82 esophageal specimens. Our topographical analysis showed that the upper mucosal glands, lower mucosal glands, and submucosal glands are occupying respectively 0.02%, 2.61%, and 3.96% of the esophageal surface. DNA synthesis and mitotic index values in the progenitor zone of the squamous epithelium were respectively 7.91% and 0.81%, whereas the proliferative activity in the glands was extremely low. The labelling index In the excretory ducts of the glands was only 0.07%, while no labelled cells nor mitotic figures were observed in any of the glandular acini.     

The structure of the glands in the angulus oris of the Bank vole Clethrionomys glareolus

The presence of glands opening to the angulus oris region of the bank vole Clethrionomys glareolus has been confirmed. The glands are similar in general to the apocrine sweat glands of man and other animals although histological differences were noted. Also there was a marked sex difference in the diameters of the lumens of the secretory tubules in this study (undertaken in the late autumn and early winter) The hairs into which the glands open are larger than other hairs in the region, and the surface pattern of the scales is inverted.     

Immunohistochemical evidence for the presence of progesterone receptor in rat submandibular glands.

Immunohistochemical analysis of progesterone receptor was carried out in rat submandibular glands. Immunoreactivity to progesterone receptors was found in cell nuclei of the intralobular duct system within male and female rat submandibular glands. The female glands contained more immunoreactive cells than the male glands. In ovariectomized rats progesterone receptor-containing cells decreased in number while testectomized glands revealed an increase. When estradiol was administered to gonadectomized rats of both sexes, the immunoreactivity in cells of the intralobular duct system markedly increased. These results suggest the possibility that progesterone may modulate various metabolic functions in the rat submandibular glands.     

Lectin binding of surface epithelia and concomitant glands of gallbladder and biliary ducts in the guinea pig

Complex carbohydrate components of secretory granules and the glycocalix were analysed in surface epithelia, endoepithelial glands and exoepithelial tubuloalveolar glands of the biliary-ductular system (guinea pig). Brunner glands and pyloric glands were studied for comparison. The columnar epithelial cells of the gallbladder and biliary ducts displayed a well-developed PAS-positive apical glycocalix. These materials strongly bound Ricinus communis A I, Ulex europaeus I, Lotus tetragonolobus A and wheat-germ-A lectins. With the exception of Lotus A lectin which did not bind at all, the same lectins stained the basolateral cell surface. The secretory granules in the supranuclear regions of surface epithelia and in the exoepithelial glands strongly bound Ricinus A I, Ulex europaeus I, wheat-germ-A and Helix pomatia lectins. Concanavalin A was less intensively bound by the secretions of tubuloalveolar glands than by the secretory granules in surface epithelia. The luminal and basolateral cell surfaces of glandular cells in the exoepithelial glands were stained by the same spectrum of lectins as were the columnar cells of surface epithelia, but the staining was less distinct. In the guinea pig, the lectin-binding patterns of tubuloalveolar glands in the biliary ducts closely resembled those of Brunner glands and pyloric glands. The secretions of the tubuloalveolar glands were different from the secretion of surface epithelia, as they bound Concanavalin A less intensively.     

Immunohistochemical analysis of estrogen receptors in cystic-endometritis-pyometra complex in the bitch

Monoclonal antibodies to human estrogen receptor were used with an indirect immunohistochemical technique to localize in formalin-fixed, paraffin-embedded sections of the genital tract of the bitch. The presence of estrogen receptors in the uterus of dogs with cystic hyperplasia endometritis complex (CHE) was compared with normal uteri from dogs at the same stage of estrous cycle. Lower estrogen receptor expression was found in the squamous metaplastic epithelium covering the luminal surface of the endometrium from dogs with CHE than in the columnar epithelium from normal dogs. In contrast, the basal glands from uteri of CHE group dogs contained more estrogen receptor than glands from normal dogs at the same stage of estrous cycle. This was most pronounced and statistically significant in the late secretary stage of the estrous cycle. When the glands presented cystic degeneration, the estrogen receptor labeling was less pronounced. The highest estrogen receptor score was present in normal glands from dogs treated with progestins. In this group even cystic degenerated glands contained high estrogen receptor concentrations compared with those of the other groups. From this study it was concluded that the down regulation of estrogen receptor expression in the endometrial glands under the influence of rising progesterone concentrations is defective in dogs with CHE. Therefore it is suggested that the regulation of estrogen receptor expression in endometrial glands may play an important role in the pathogenesis of CHE in the bitch.     

Activity of the prothoracic gland and its sensitivity to prothoracicotropic hormone in the penultimate and last-larval instar of Bombyx mori

The time course of secretion of ecdysone in vitro by the prothoracic glands of Bombyx mori was studied through the penultimate and last-larval instars. Ecdysone was produced by the glands in high amounts by the penultimate instar at 72 and 84 h while the glands in the last instar exhibited a high activity over 4 days around the time of gut purge and thereafter. The glands in the penultimate instar produced ecdysone at a low level throughout the instar before the sharp peak of activity, when they became inactive and remained so for the first 3 days of the last instar after when they regained secretory activity. Sensitivity of the glands to prothoracicotropic hormone varied in accord with the changes in their secretory activity. Inactive glands were not stimulated by 22K-prothoracicotropic hormone. In addition, glands with maximal activity in the penultimate instar were insensitive to 22K-prothoracicotropic hormone. These results suggest that the prothoracic glands in the penultimate and last-instar larvae are physiologically different.     

Some histochemical studies on the prostate, urethral and bulbourethral glands of the one-humped camel (Camelus dromedarius)

Synopsis The histochemical localization of carbohydrates, ribonucleoproteins (RNA), lipids, some hydrolytic enzymes, succinate and lactate dehydrogenase and acetylcholinesterase were investigated in the prostate, urethral and bulbourethral glands of the camel. These glands probably secrete carbohydrate-protein complexes. In the bulbourethral glands, they are sulphated mucopolysaccharides. RNA was seen in the cytoplasm of the prostate and urethral glands. Neutral lipids were cytoplasmic and present in moderate amounts in the prostate and urethral glands and in traces, in the bulbourethral gland. Acid phosphatase-containing granules were abundant in the prostate, moderate in the urethral glands and in traces in the bulbourethral glands. Alkaline phosphatase was observed in the apical cytoplasm of the prostate and bulbourethral glands and in the ducts of the urethral glands. ATPase and adenosine 5-monophosphatase were seen in the basal laminae and interstitial tissue. In the urethral glands, adenosine 5-monophosphatase was distributed diffusely in the cytoplasm. Succinate dehydrogenase was seen in the urethral and bulbourethral glands. Varying degrees of lactate dehydrogenase activity was observed in all the glands. Acetylcholinesterase was confined to neural elements. The pars disseminata and the urethral glands were considered as two distinct glandular zones along the pelvic urethra. The significance of these histochemical results is discussed.     

Testicular and androgen dependence of skin gland morphology in the anurans,Xenopus laevis and Rana pipiens

In anuran amphibians, there is increasing evidence that exocrine glands dispersed throughout the general integument are secondary sex characters (SSC). Following the recent discovery of sexually dimorphic “breeding glands” in the dorsum of male Rana pipiens, we studied the effects of castration and testosterone treatment on the dorsal skin glands of male Xenopus laevis and R. pipiens to determine whether the dorsal breeding glands, or any other dorsal skin glands, are androgen dependent. The dorsal skin glands of X. laevis were unaffected by androgen status. By contrast, in R. pipiens, breeding, mucous, and seromucous glands responded to testosterone stimulation. Mucous glands were significantly (P < 0.05) larger in testosterone-treated frogs than in castrates. There was a large, but statistically insignificant, increase in the size of the dorsal breeding glands. Testosterone treatment also increased the epithelial cell height of breeding and seromucous glands (P < 0.05). In the skins of castrated and testosterone-treated frogs, there was a reciprocal relationship between the abundance of seromucous and breeding glands: in castrates, seromucous glands were abundant and breeding glands virtually absent, whereas in testosterone-treated frogs, breeding glands were abundant and seromucous glands less common. The total number of the two gland types was similar in both treatment groups. Glands that appeared to be intermediate in form between seromucous and breeding glands were observed in some frogs. These data suggest that seromucous glands may be the regressed form of breeding glands in the dorsal skin of R. pipiens and that the dorsal skin of R. pipiens is a SSC. © 1993 Wiley-Liss, Inc.     

Secretory and structural changes in the parotid salivary gland of sheep and lambs after parasympathetic denervation.

The effect of the parasympathetic nerve supply on the development of the parotid gland in the immature lamb and its maintenance in the adult sheep has been investigated by unilateral postganglionic denervation. Seventy-seven to ninety-three days after denervation secretory activity of the gland was examined and material taken for histological examination. The adult denervated glands secreted at lower rates than the innervated and their atropine-resistant secretory flow was reduced to as low as one fifth of that of the innervated glands. In two lambs an atropine-resistant flow did not develop in the denervated glands: in another two, flows of saliva from the denervated glands were present but were much less than in the contralateral innervated glands. After denervation glands were, with one exception, smaller than the contralateral innervated glands. The acinar cells of the denervated adult and lamb glands were smaller than the cells of the innervated glands but similar in size to those of 7-14 day old unoperated control lambs. Acinar cells in denervated glands had periodic acid Schiff staining material but the staining reaction to pyronin-methyl green was similar in the innervated and denervated. The results indicate that the integrity of the parasympathetic innervation is essential for the development of the parotid gland of the sheep and for its maintenance in the adult animal.     

A histochemical study of catecholamines and cholinesterases in the autonomic nerves of the human minor salivary glands

Synopsis The cholinergic and adrenergic innervation of human minor sublingual buccal and labial salivary glands has been studied with histochemical techniques for localizing acetylcholinesterase and catecholamines. A rich cholinergic innervation was observed around the acini, blood vessels and some ducts of the three glands.The adrenrgic innervation, however, was virtually absent from the parenchyma although present around the blood vessels, in marked contrast to the dense parenchymal adrenergic innervation observed in the human parotid and submandibular glands. These results suggest that the autonomic nervous mechanism which regulates salivary secretion is more elaborate in the major than in the minor salivary glands.     

Structure-activity relationships in corpora allata of the cockroach Diploptera punctata: roles of mating and the ovary

Morphometric studies were made on corpora allata of the cockroach Diploptera punctata from animals in which increasing gland size is not coupled to hormone synthesis (ovariectomized mated females; last-instar larvae) and in which gland size is coupled to hormone synthesis (normal mated and virgin females; penultimate-instar larvae). Cell number, gland volume, and juvenile hormone synthesis were measured. From electron micrographs, nuclear, cytoplasmic, and extracellular volumes; and cell membrane area were calculated; and fine structure described. Low-activity glands of ovariectomized mated females resembled high-activity glands from mated females in high cell number, large overall and cytoplasmic volume, and low nuclear-cytoplasmic ratio; they differed in having organelles typical of low-activity glands, mitochondria with dense matrices and large whorls of smooth endoplasmic reticulum. Inactive lastinstar larval glands resembled mated ovariectomized, female glands in increased cell number and organelles characteristic of inactive glands; however, their nuclearcytoplasmic volume ratio was much higher. Penultimate cytoplasmic volume ratio was much higher. Penultimate larval glands with high activity per cell resembled active glands of normal mated females. Ovariectomy did not change morphometric parameters of virgin female glands; thus mating results in increase in size of adult female glands whereas the growing ovary is needed for changes in mitochondria and endoplasmic reticulum associated with high juvenile hormone synthesis.     

Hyperforin accumulates in the translucent glands of Hypericum perforatum

BACKGROUND AND AIMS: Hypericum perforatum contains the therapeutically important compounds hypericin and hyperforin. Hypericin is known to accumulate in the dark glands. This investigation aimed to determine the accumulation site of hyperforin. METHODS: Dark and translucent glands as well as non-secretory tissue in leaves were manually isolated under the microscope. Hyperforin content was quantified by UV HPLC. Secretory structures were surveyed anatomically. KEY RESULTS: The hyperforin content of intact leaves was found to be about 3 mg g(-1) fresh tissue, whereas a content of about 7 mg g(-1) fresh material was found in isolated translucent glands. Hyperforin was found only to occur in minute amounts in dark glands (approx. 0.4 mg g(-1) fresh tissue). In non-secretory tissue no hyperforin was detected. CONCLUSIONS: The accumulation of hyperforin detected in the translucent glands supports the proposed hypothesis that hyperforin is synthesized by the same biosynthetic machinery as monoterpenes in the chloroplasts of cells delimiting the gland.     

Respiration of larval salivary glands of Drosophila in relation to the activity of specific genome loci

Oxygen consumption of intact larval salivary glands of Drosophila hydei was measured after the addition of intermediates of the citric acid cycle or amino acids to the incubation medium. The effect of these substances on respiration of glands previously submitted to anaerobiosis in vivo was compared with that of glands of control larvae. Only isocitrate and tyrosine stimulated respiration of anaerobically treated glands to a much higher extent than glands of control larvae. This stimulatory effect was abolished when RNA or protein synthesis was inhibited. It is suggested that some of the specific puffs occurring as a consequence of anaerobiosis reflect gene activity required for an increase in utilization of isocitrate and tyrosine for respiration under conditions of stress.     

Melatonin in the lacrimal gland: first demonstration and experimental manipulation

NAT, HIOMT and melatonin are described in the extra-orbital lacrimal glands. The extra-orbital lacrimal glands of female Syrian hamsters contain higher NAT activity and melatonin levels than those in male glands, while male glands have higher HIOMT activity. Castration did not change melatonin in the lacrimal glands, although NAT and HIOMT activities were altered. The exposure of female hamsters to light in the morning (0600h) was associated with a reduction in both NAT activity and melatonin levels. Porphyrins were not detected in the lacrimal glands of either male or female hamsters.     

Endocrine cells of the esophageal glands]

Distribution of endocrine cells in the human oesophagus was studied histochemically. Large amount of endocrine cells was discovered in terminal parts and excretory ducts of the cardial glands. Endocrine cells of the oesophageal cardial glands are represented, at least, by three types: argentaffine, argyrophil in the reactions of Grimelius and Sevier, Munger and argyrophil in the reaction of Grimelius only. The amount of argentaffine cells in the oesophageal cardial glands was observed to be 5 times as large as that of in the gastric cardial glands. The reason is evidently in functional difference of the oesophageal and gastric cardial glands. The endocrine cells were absent in the mucous glands of the oesophagus.