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Airway submucosal glands are by volume the most important source of macromolecules in airway secretions. These secretions, containing gel-forming mucins, antibacterial proteins, and antiproteases, comprise the major defensive barrier protecting the host against airborne pathogens. The identification of the mechanisms regulating secretion from the submucosal glands is key to understanding the genesis of this barrier and how it is altered by disease processes. Using a variety of methods, we and others have identified on the gland cells of several species receptors specific for ACh, norepinephrine, substance P, VIP, PGE1, PGE2, PGA1, PGD2, histamine and bradykinin. These receptors all participate in modulating the secretory activity of the airway submucosal glands. Studies of homogeneous cultures of bovine airway serous cells have yielded detailed information regarding the beta-adrenergic receptor on these cells. Using radioligand binding techniques, we found evidence for the presence of a single high affinity beta receptor of beta-2 subtype. Occupancy of this receptor by isoproterenol causes an elevation in the concentration of intracellular cAMP, which in turn stimulates the phosphorylation of a subset of cytoplasmic and membrane proteins. Based on the kinetics and pharmacology of these effects, it is likely that cAMP functions as a second messenger in the serous cell secretory pathway, probably acting through protein kinases. Current efforts are directed at identification of those phosphoproteins whose phosphorylation and dephosphorylation times are consistent with their possible roles in secretion.

The presence of vitelline cells in male Schistosoma mansoni from both mixed ans single sex infections in mice is described. Ultrastructurally these vitelline cells resemble the mature, Stage 4 cells from normal female worms. As yet no developing vitelline cells (Stages 1 to 3) have been found. The cells do not appear to form complete lobules as in the female.

This study examines the structure of mucosal glands in the walls of the hamster maxillary recess, compares the histochemical appearance of nasal glands to their sialic acid content, and determines the vulnerability of nasal glands to actinomycin toxicity. Observations were made on plastic-embedded tissue with light and transmission electron microscopes. Determinations of total sialic acid in mucosal samples were conducted with thiobarbituric acid. Experimental hamsters were administered 0.2 micrograms of actinomycin D (IP)/gm body weight/day for five days. Types of granules present in the later nasal gland (LNG) and glands of the maxillary recess (MRGs) include: 2.0 micrometers lightly basophilic, lightly electron-dense granules and 1.5 micrometers strongly basophilic, electron-dense granules in the same acinar cell type in both the LNG and MRGs; 1.5 micrometers metachromatic granules in some acinar cells of the LNG; 1.0 micrometer moderately electron-dense granules in cells of MRG ducts; and 0.7 micrometers electron-dense granules in cells of LNG intercalated ducts. Acid glycoproteins, demonstrable by histochemistry, are present in the LNG but not in the MRGs. However, the total sialic acid content of tissues from MRG tissue is greater than that of other tissues measured. A minor number of LNG acini, those with metachromatic granules, have branching basal cytoplasmic projections. Many dark cells are present in striated ducts of the LNG. Histological alteration due to actinomycin-D toxicity, conspicuous in parotid salivary parenchyma, is greater in MRG than in LNG tissue.

Three muscarinic acetylcholine receptor subtypes may be defined on the basis of functional and binding studies using selective antagonists. The subtypes may be solubilized in a stable form in digitonin. In solution, the subclasses still exhibit different structure-binding relationships but these have been perturbed by solubilization. The binding of the selective antagonist, pirenzepine, to the purified cortical receptor is complex and similar to that found in membranes. The muscarinic receptor subclasses thus appear to be different molecular entities. Possible explanations for the molecular heterogeneity are discussed. It has also been possible to solubilize receptor-GTP binding protein complexes which have higher sedimentation coefficients (13.4 S) than the apparently monomeric receptor (11.6 S).

Seven novel polyhydroxylated steroids were isolated from the nucho-dorsal glands of the snake, Rhabdophis tigrinus. Biological activities of these steroids in inhibiting (Na+ + K+)ATPase and in producing positive inotropic action were examined in comparison with those of ouabain and gamabufotalin. Gamabufotalin was approximately 10 times more potent than ouabain in inhibiting (Na+ + K+)ATPase. Two compounds, compounds III and XIII, of the seven, produced nearly equipotent enzyme inhibitory activity to ouabain. The activity of the remaining five was relatively low among the compounds tested. All compounds exhibited more or less positive inotropic action in the papillary muscle preparations. The ranking order of the potency was: gamabufotalin greater than ouabain and compound IV greater than compound III and XIII greater than compound I, II, XII and XIV.

The distal upstream region of the fibroin gene, -238 to -73, is known to contain the cis-acting element(s) responsible for tissue-specific transcription enhancement in vitro. To identify factor(s) trans-acting on this region, we have developed a modified nitrocellulose blot protein-DNA binding procedure that detects DNA-protein complexes via protein-protein interaction. A protein that does not bind to DNA as a monomer cannot be detected by standard Southwestern blotting. To detect protein-DNA complexes involving both protein-DNA and protein-protein interactions, the protein blot was reacted with the extract protein to form a protein complex on the filter, in the presence of the DNA probe. This new method revealed that the 75-kDa protein binds to the enhancer region of the fibroin gene in the presence of the second protein(s). The 75-kDa protein and the factor(s) mediating DNA binding activity were recovered in two different column fractions. The level of the 75-kDa protein appeared to be much higher in silk gland extracts than in nonsilk gland extracts, whereas the mediating factor(s) distributed evenly. These observations suggest that the distal upstream region of the fibroin gene can be specifically recognized by a protein complex composed of at least two distinct proteins, through protein-protein interaction.

In order to elucidate whether Salivary Protein C and salivary peptide P-C, originally isolated from human saliva were present in tissues other than those of the salivary glands or not, an indirect immunofluorescence technique using both antisera against salivary peptide P-C and Salivary Protein C was carried out on human salivary glands and the human respiratory tract. As salivary peptide P-C-like immunoreactivity was detected in the serous cells of salivary glands by previous immunohistochemical study, the human respiratory tract was closed as model tissue, since tracheal and bronchial glands in the human respiratory tract consist of mucous and serous cells. Furthermore, to check whether salivary peptide P-C is a fragment of Salivary Protein C or not, the same immunohistochemical study was undertaken on the serial sections of salivary glands and the respiratory tract. Salivary peptide P-C and Salivary Protein C-like immunoreactivities were present in the serous cells of human salivary glands and in tracheal and bronchial cells. Furthermore, the same serous cells were immunostained with antisera against salivary peptide P-C, with antisera against Salivary Protein C and with antisera against Salivary Protein C preabsorbed with salivary peptide P-C. In view of the fact that the full sequence of salivary peptide P-C is identical to the COOH terminal 44 amino acid residues of Salivary Protein C, it was suggested that the full sequence of Salivary Protein C was present in the serous cells of human salivary glands and in those of tracheal and bronchial glands and that salivary peptide P-C was a fragment of Salivary Protein C.(ABSTRACT TRUNCATED AT 250 WORDS)

Wax esters constitute the major products of the uropygial glands of male mallard ducks (Anas platyrhynchos). Combined gas-liquid chromatography and mass spectrometry of the acyl and alcohol portions of the wax ester revealed dramatic seasonal variation. Of the total of nearly 100 compounds detected in the acyl portion, more than 90 were identified as n-, monomethyl-, dimethyl-, and trimethyl-C6 to C20 acids. The major components were 2-methyl- and 4-methyl C6 acids which constituted nearly 75% of the total acids during most of the year. As the birds went through the post-nuptial molt into eclipse, these short chain acids decreased to only 4% of the total acids. Fatty acids longer than C12 became the major components during the summer months when the birds were in eclipse and by fall the characteristic shorter branched acids reappeared as the dominant components. Fatty alcohols did not undergo such dramatic changes. This is the first report of biochemical changes that occur during eclipse.

Two histophysical methods (electron microprobe and ion microanalyzer) were used on sections of Annelids in order to study the inorganic composition of cement secretory glands. Mg, Ca and P were demonstrated in large amounts in the secretions, associated with organic matter. Traces, or no, Fe, Al and Si were found. Possibilities of artifacts are discussed, and these results are compared with biochemical methods. A hypothesis is proposed in order to explain the differences observed between biochemical and present results, which suggest, for the hardening of cements a different chemical mechanism to that suggested by Vovelle in annelid Sabellaria alveolata.

The two pairs of lobes of the calciferous gland if the earthworm Lumbricus terrestris are specialized oesophageal diverticulae that secrete spherites ranging from 0.5 - 7.0 micrometers in diameter. Correlative transmission and scanning electron microscopy indicated that the spherites (which are predominantly CaCO3) are formed extracellularly in distinctive bays bounded by secretory-cell processes, and are mobilized anteriorly from the gland lumina to the lumen of a non-secretory pouch, where the majority coalesce and undergo phase transformation to concretions 0.5 - 1.0 mm in diameter consisting of a mass of cuboidal crystals with facets up to 40 micrometers. The distribution of Sr(0.1 ml 5% SrCl2 injected into the posterior coelomic cavity) was monitored in the mineralized secretory products of the calciferous glands by X-ray microanalysis of 10 micrometers - thick air-dried cryostat sections in a SEM. Strontium was not detected in chloragosomes at 2h and 24h post-injection. Strontium was transported anteriorly and specifically incorporated into gland spherites (detectable within 2h). This technique of Sr localization afforded sufficient structural and analytical resolutions to provide a confirmation of the sequence of extracellular changes in the gland/pouch system. In addition we were able to distinguish a population of growing spherites from the vast majority of mature spherites; size alone was a singularly poor indication of spherite growth. The major element constituents of the chloragosomes were P, Ca and Zn (Ca: P ranging from 0.4 to 1.0; Zn: P from about 0.05 to 0.45). Analysis of individual spherites showed that Ca was probably bound to P or P-containing matrix components, whilst Zn was probably linked to one or more different but unknown constituents.

In a posterior silk gland extract, covalently closed circular (ccc) DNA is in a superhelical state that supports more transcription of fibroin gene than does linear DNA. A HeLa cell extract showed neither the supercoiling activity nor the preference for the transcription of ccc DNA over linear DNA. These activities could be added to the HeLa cell extract. Phosphocellulose fractionation of the posterior silk gland extract yielded a flow-through fraction and a 0.6 M KCl eluate fraction that were required for the supercoiling and for the efficient transcription of the ccc template in the acceptor HeLa cell extract. The 0.6 M KCl fraction had a DNA topoisomerase II activity, and the flow-through fraction contained a supercoiling factor that, with the aid of topoisomerase II, introduced negative supercoils into ccc DNA. When both fractions were added to the posterior silk gland extract, more supercoiling occurred than with the extract alone. Several genes were optimally transcribed under various extents of supercoiling. The fibroin gene and adenovirus 2 major late promoter were fully transcribed as partially supercoiled templates. The sericin gene required more supercoiling for full transcription, whereas no preference for supercoiling was seen with the transcription of hsp70. These results suggest that DNA topology plays a role in the regulation of gene expression.

Lipids were extracted from excised uropygial glands of domestic chickens and the wax diesters were isolated by preparative thin-layer chromatography (TLC). The diesters were hydrolyzed and the liberated diols were resolved by boric acid TLC into two fractions. These were investigated by proton magnetic resonance at 360 MHz of the free diols and of their acetonide derivatives. The results showed that the cis and trans acetonides, formed from the erythro and threo isomers of the diols, respectively, could be distinguished by the degree of magnetic nonequivalence of the two acetonide methyl groups in each molecule. On the presumption that the cis isomer should show the greater nonequivalence of the methyl groups, this configuration was assigned to the acetonides of these diols which had the lesser TLC mobility on boric acid/silica gel. This agrees with the assignment of configuration made by earlier workers on the basis of the relative TLC mobility of the diol isomers on boric acid/silica gel, but was contrary to a previous assignment based on gas-liquid chromatographic (GLC) retention times. We conclude that the erythro isomers of the diols are characterized by lower mobility on boric acid TLC, as well as on silica gel TLC, and form acetonides that have longer retention times on GLC, and greater nonequivalence of the acetonide methyl groups in the NMR spectrum, than do the acetonides of the threo isomers.

Secretory epithelia and ductular glands were studied in main pancreatic ducts of guinea pig, rabbit, rat, and man. Brunner glands were studied for comparison. Semithin sections from Epon-embedded tissues were etched with sodium methylate and incubated with horseradish peroxidase-conjugated lectins. Columnar cells in the epithelium of pancreatic ducts are endowed with well-developed microvillar borders. These apical regions strongly stain with Lotus A-, wheat germ-, and Ricinus I-lectins. Basolateral plasma membranes bind Ricinus I-, Ulex europaeus I-, and wheat germ-lectins. Cytosomes in the supranuclear regions of epithelial cells are interpreted as secretory granules. These droplets are marked by wheat germ-lectin and to a lesser degree by Ricinus I- and Ulex europaeus I-lectins. Ductular glands of the main pancreatic ducts contain secretions that bind Helix-, wheat germ-, and Ulex europaeus I-lectins. Their apical and basolateral cell membranes deeply stain with wheat germ- and Ulex europaeus I-lectins. Secretions of Brunner glands bind Ricinus I-, Ulex europaeus I-, Helix-, and wheat germ lectins. Their apical and basolateral cell membranes stain with Ricinus I- and wheat germ-lectins. - Species differences in lectin-binding affinities of complex carbohydrates were observed and are described.

The cercariae of Eurytrema pancreaticum (Janson, 1889) possess four types of gland cells - proper cystogenic, penetration, ventral and dorsal gland cells. The secretion of ventral and dorsal gland cells is released into the tegument. The proper cystogenic gland cells are the largest and their contents serve for the formation of the cyst wall of metacercariae in the second intermediate host. The secretion of proper cystogenic gland cells contains besides neutral mucosubstances also acid mucosubstances with both carboxyl- and sulphogroups digestible with beta-glucuronidase. The secretion of penetration gland cells contains neutral mucosubstances and proteins with tyrosine, tryptophan and SS groups. The ventral gland cells contain mostly acid mucosubstances with sulphogroups, which are digested with beta-glucuronidase, and proteins with tyrosine, tryptophan and SH groups. The rudimentary dorsal gland cells contain a small amount of acid mucosubstances. The whole tegument of cercariae and the two main collecting canals of the excretory system exhibit a high alkaline phosphatase activity. The nerve ring and the main nerve truncs contain proteins with SH groups and hydrophilic lipids and exhibit a cholinesterase activity. The suckers contain a larger amount of glycogen.

Experimentally applied irritants and chronic respiratory diseases appear to alter the amount and composition of secretory cell product in surface epithelium and submucosal glands of pulmonary airways. Previous methods used to quantify these changes have been very time-consuming or have not measured the same components of the airway wall. The present study describes a rapid, reproducible, and standardized automated method for quantifying secretory products. The tracheas from eight macaque monkeys were fixed with glutaraldehyde-paraformaldehyde, embedded in glycol methacrylate, serially sectioned at 2 microns, and histochemically stained to demonstrate neutral, sialylated, and sulfated mucosubstances in the cartilaginous, intercartilaginous, and membranous regions of both proximal and distal trachea. Volume densities were determined using an image analyzer and are expressed as volume of stained mucosubstance per unit surface area of epithelial basal lamina. Comparison of the automated method to manual point counting and evaluation of internal variance showed that the automated method had a twelve-fold increase in efficiency with no significant differences in measurements. After weighting the values of each region according to their anatomical contribution, the total secretory product (TSP) for the entire trachea was determined. Periodate-reactive acid material predominated (73%) in luminal surface epithelium, and neutral material predominated (78%) in submucosal glands. Surface epithelium contained 66% of the TSP. The greater contribution by surface epithelium and predominance of acid mucins there resulted in a TSP from the trachea that consisted of 59% acid material (most of which was sulfated) and 41% neutral material. The method proved to be a valid, reproducible, and rapid technique for evaluating variability in abundance of mucosubstances within airway epithelium.

1. R2 and LPl1 are homologous giant cholinergic neurons in the nervous system of Aplysia with overlapping and almost symmetrical axonal trees extending over most of the body wall. In spite of much experimental study, the behavioral role of the cells has remained unknown. 2. After intrasomatic injection of R2 and LPl1 with horseradish peroxidase (HRP), the giant cell axons were traced to the periphery and found to contact subepidermal glands in the body wall exclusively. 3. The axons penetrated the glandular basal lamina, indenting the gland cell cytoplasm, and expanded into varicosities containing putative cholinergic transmissive sites. 4. Histochemical characterization of the contents of the glands showed that they contain mucus, suggesting that the giant cells control mucus release from the body wall. 5. Stimulation of R2 or LPl1 resulted in glandular discharge, as measured both by an increase in the appearance of protein and of mucus on the body wall. 6. R2 and LPl1 control mucus release from the body wall, thus providing a new system for investigations of neuroglandular control as well as a behavioral context for cellular studies using these two neurons.

Complex carbohydrates were examined in glandular cells of the horse duodenal gland by using lectin histochemical techniques. In the horse, the duodenal gland was distributed in the area from the uppermost part of the small intestine to a point about 6m caudal to the pylorus. It consisted of two types of cells, mucous and serous cells. The former was found in glands distributed almost all over this part, but the latter was present in glands distributed restrictedly to the uppermost part of the small intestine at a point about 10 cm caudal to the pylorus. The cytoplasm of the mucous cell contained neutral glycoproteins with different saccharide residues as alpha-D-mannose, N-acetyl-beta (1----4)-D-glucosamine, galactose, alpha-galactose, alpha-N-acetylglucosamine, beta-D-Gal (1----3)-D-GalNAc, alpha-L-fucose and sialic acid. On the other hand, the serous cell contained neutral and acid glycoproteins with different residues such as alpha-D-mannose, alpha-D-glucose, beta-D-galactose(1----3)-D-N-acetylgalactose, alpha-L-fucose, N-acetyl-alpha-D-galactosamine, N-acetyl-beta (1----4)-D-glucosamine, galactose, alpha-galactose, alpha-N-acetylglucosamine and sialic acid. It is also elucidated in the present study that lipase, an enzyme for digestion, is contained in the serous cell of the equine duodenal gland.

The characterization of a new silk protein mRNA (P25 mRNA) in posterior silkgland cells (PSG) and the developmental variations of its cell molecular concentration versus that of fibroin mRNA are described. A 80% pure P25 cDNA was obtained by class separation of total nonfibroin cDNA from PSG and used to identify the mRNA in blotted PSG mRNA as a single 1100 nucleotide long species. When purified from agarose gel and translated in a reticulocyte cell-free system, P25 mRNA yielded a 25-kD polypeptide (P25), identical to a 25-kD protein of the cocoon in terms of pI value and partial peptide mapping pattern. Moreover, this protein comigrated with an abundant polypeptide of the posterior silkgland (PSG) and of the middle silkgland (MSG). When tritiated leucine was injected in vivo, labeled P25 showed up in the PSG after a 2-hr pulse but appeared in the MSG only after 24 hr of labeling. Since MSG cells were found to be devoid of P25 mRNA, we concluded that P25 is exclusively synthesized in the PSG, that it accumulates in the MSG lumen and that it is spun out in the same way as fibroin. Specific probes were used to measure the concentrations of P25 mRNA and also fibroin mRNA in PSG total RNA by hybridization with an excess of cDNA. Both species are highly degraded in the few hours following the physiological arrest of feeding which precedes the fourth molting period. Their subsequent accumulation during the fifth intermolt is triggered by food uptake and proceeds in such a way that a constant 1:1 molar ratio is maintained during the period of silk secretion.

Three proteinase inhibitors designated as I, II, and III were isolated from the excretory gland cells of the swine kidney worm, Stephanurus dentatus. The inhibitors, which were trichloroacetic acid-soluble, were purified by affinity chromatography and ion exchange chromatography. The homogeneity of each inhibitor was shown by polyacrylamide gel electrophoresis and electrofocusing. The molecular weights of the inhibitors estimated by sodium dodecyl sulfate gel electrophoresis fell within a limited range of 9300 to 9700, and the isoelectric points were 6.45, 6.20, and 5.34 for Inhibitors I, II, and III, respectively. The inhibitors formed complexes with trypsin having apparent dissociation constants (Ki) of 2.9 X 10(-11), 7.6 X 10(-11), and 6.4 X 10(-11) M, respectively. Each inhibitor inhibits the esterolytic and proteolytic activities of both trypsin and chymotrypsin. A proteinase inhibitor present in the reproductive organs, intestines, body walls, and esophagi was identical with Inhibitor II found in the excretory gland cells. Culture medium collected after 24-h incubation with adult worms contained the same three inhibitors as the excretory gland cells. These data suggest that the gland cells may secrete the inhibitors internally and externally.

The percentage area of the bronchial glands taking up the Alcian blue (pH 2-6) stain for acid mucin was obtained from sections from the trachea and from each generation down the inferior lingular axial bronchial pathway in five non-smokers and five cigarette smokers. The mean percentage value for the smokers (59-5%) was significantly less than for the non-smokers (74-4%). The percentage increased between successive generations from the trachea by an average of 6-5. This gradient did not differ significantly between the smoking and non-smoking groups. It was not possible to attribute these differences to any specific mechanism because many interacting variables were involved which could not be measured. Nevertheless the percentage mucin retention or storage provides an introduction to consideration of these variables and their response to cigarette smoke.

This paper described a new histochemical method for the detection of sulfhydryl groups in tissue specimens using 2,6-dichloroquinone chloroimide G.R. (Merck) after the reduction of its chloride groups of sodium thiosulfate. Ths proposed mechanism of the reaction, the procedures and the histological applications are described.

Histochemical and immunohistochemical studies on 47 consecutive specimens excised for choledochal cyst were performed to clarify possible metaplastic changes of the biliary duct in relation to carcinogenesis. An anomalous arrangement of the pancreaticobiliary ductal system was observed in all 39 cases examined. Among the 47 patients, 5 (10.6 per cent) had biliary carcinoma. 27.3 per cent mucous gland, 13.0 per cent goblet cell and 9.5 per cent argyrophil cell in 23 children. On the other hand, 81.8 per cent exhibited mucous gland, 41.7 per cent goblet cell and 27.3 per cent argyrophil cell in 24 adults. These metaplastic changes seemed to be an intestinal metaplasia and increased with age. Immunoreactive-gastrin or -somatostatin were evident immunohistochemically in 4 adults. These findings confirmed that intestinal metaplasia may develop in the biliary duct in cases of choledochal cyst. Although direct evidence between intestinal metaplasia and the development of biliary carcinoma was not found, reflux and stasis of pancreatic enzymes in the biliary duct may relate to the development of intestinal metaplasia and be an important factor related to the carcinogenesis of choledochal cyst.

Fixation of prothoracic glands of Galleria mellonella with a solution containing saponin permits immunocytochemical staining of the entire gland. By this means ecdysteroids were demonstrated electron microscopically to be present in the hyaloplasm and microtubules.

Histochemical studies on the uropygial gland of domestic fowls have shown the presence of sterols (among which cholesterol and its esters) in the lipidic fraction of the gland secret. beta-Glucuronidase activity beside A5 3beta- and 17beta-hydroxysteroid dehydrogenase activities suggests that uropygial gland might be involved in sterols metabolism. By thin layer chromatography cholesterol and 7-dehydrocholesterol can be separated from the uropygial extracts and these compounds can be identified in gas liquid chromatography.

Numerous glandular elements are characteristically found within and around the intrahepatic bile duct walls in hepatolithiasis. These glandular elements were studied by reconstruction of serial sections and mucus histochemistry. The glands were of two types: glands within the thickened ductal wall (intramural) and those outside the wall (extramural). The former were mucous glands arranged in tubular pattern and the latter seromucous glands arranged in tubuloalveolar pattern. Mucous acini of both glands were rich in neutral, carboxylated and sulfated mucus glycoproteins. Serial section observations showed that the intramural glands communicated with bile duct lumina directly, and the extramural glands with ductal lumina via their own conduits. The intramural glands were usually continuous with the epithelia lining bile ducts, suggesting that they were derived from an invagination and subsequently proliferating epithelium lining bile ducts. The extramural glands may have arisen from a proliferation of the pre-existing peribiliary glands. Hypersecreted mucus from the intramural and extramural glands might be causally related to the development and growth of calculi in the intrahepatic biliary tree.

Aplysianin-A, an antibacterial and antineoplastic factor in the albumen gland of the sea hare Aplysia kurodai, was isolated. It had a molecular weight of approximately 320 kD and consisted of subunits with a molecular weight of 85 kD. It contained 9.8% neutral sugar. Aplysianin A showed 50% inhibition of Bacillus subtilis growth at a concentration of 4 microgram protein/ml and 50% lysis of murine MM46 tumor cells at 14 ng protein/ml. A partial identity of antigenic specificity of the purified specimen with an antineoplastic factor from Aplysia eggs was observed in immunodiffusion tests.

A highly purified membrane preparation from rat parotid secretion granules has been used as a comparative probe to examine the extent of compositional overlap in granule membranes of three other exocrine secretory tissues--pancreatic, lacrimal, and submandibular--from several standpoints. First, indirect immunofluorescent studies using a polyclonal polyspecific anti-parotid granule membrane antiserum has indicated a selective staining of granule membrane profiles in all acinar cells of all tissues. Second, highly purified granule membrane subfractions have been isolated from each exocrine tissue; comparative two-dimensional (isoelectric focusing; SDS) PAGE of radioiodinated granule membranes has identified 10-15 polypeptides of identical pI and apparent molecular mass. These species are likely to be integral membrane components since they are not extracted by either saponin-sodium sulfate or sodium carbonate (pH 11.5) treatments, and they do not have counterparts in the granule content. Finally, the identity among selected parotid and pancreatic radioiodinated granule membrane polypeptides has been documented using two-dimensional peptide mapping of chymotryptic and tryptic digests. These findings clearly indicate that exocrine secretory granules, irrespective of the nature of stored secretion, comprise a type of vesicular carrier with a common (and probably refined) membrane composition. Conceivably, the polypeptides identified carry out general functions related to exocrine secretion.

To characterize proteins that bind to the upstream region of the fibroin gene, we used an electrophoretic mobility assay and a DNase I footprinting assay. A crude nuclear extract from the posterior silk glands forms a sequence-specific complex with the upstream region, -234 to -66, which includes a signal for tissue-specific transcriptional enhancement. This specific complex is composed of at least two factors of proteinous nature and the DNA. The composite proteins specifically protect an approximately 13-base pair (-167 to -155) region in a DNase I footprinting assay. This region contains an interesting repeated sequence, AATTTAATTT. Crude nuclear extracts from the middle silk glands and the ovarian tissues, but not a HeLa whole cell extract, also give the band complexes of similar electrophoretic mobility to the one formed in the posterior silk gland extract. However, under a higher EDTA condition, these complexes are more unstable than the one constructed in the posterior silk gland extract. These results suggest a possibility that these proteinous molecules in the complex, although apparently ubiquitous in Bombyx cells, might be specifically modified in the posterior silk gland cells to play an important role in the specific expression of the fibroin gene.

The concentrations of eight metals were determined by a nondestructive neutron activation technique for eleven species of fish and shellfish. The marine organisms were collected from ocean dump sites off New York City, off New Haven, Connecticut, and off Delaware Bay. Antimony was not detected in most of the organisms examined in thid study; the detection limit was about 0.02 to 0.05 ppm. Antimony levels ranged from 0.01 to 0.129 ppm in fish that had detectable levels. Cobalt levels were low in all samples with most levels in the range of 0.1 to 0.3 ppm. Chromium concentrations at 0.3 to 1.0 ppm were only roughly quantitated by the procedure employed. Most marine organisms examined had chromium levels at or below these values. Nickel was not detected in any of the organisms examined; the detection limit was in the 3 to 6 ppm range. Rubidium concentrations were 0.6 to 1.5 ppm for most organisms; only rough quantitative measurement was possible at these levels. Selenium levels ranged from about 0.3 to 3.8 ppm in all samples. Silver concentrations were below 0.3 ppm in most organisms. Silver concentrations as high as 10 to 30 ppm, however, were found in the digestive gland of rock crab. Zinc levels in windowpane flounder liver were about 6 to 9 times greater than the 4 to 10 ppm levels found in muscle. Zinc concentrations in rock crab muscle, on the other hand, were only slightly higher than the 15 to 32 ppm concentration found in the digestive gland. Fish other than windowpane flounder had zinc levels that ranged from 4 to 9 ppm in the muscle and 14 to 42 ppm in the liver. Shellfish other than rock crab had zinc levels of 15 to 30 ppm in muscle and 17 to 40 ppm in the digestive gland.

Immunoreactive prolactin was demonstrated in the acinar cells of urethral glands in some inbred strains of mice by immunoperoxidase technique. The significance of the presence of prolactin or its related substances in the urethral glands in relation to their role in the urinary tract is discussed.

The secretion of the nasal gland from the marsh deer (Odocoileus dichotomus) has shown to be a lipid mixture predominantly containing cholesterol esters, mono- and diester waxes, the latter of which containing 2-hydroxy fatty acids. The alcoholic constituents of the mono- and diester waxes contain considerable amounts of mono-unsaturated homologues, all with the double bonds in (omega-9)-position.

Immunohistochemical localization of smooth muscle myosin, an immunologically distinct contractile protein, was achieved using rabbit anti-human uterine smooth muscle myosin antibodies. In immunodiffusion studies and in cryostat sections, these antibodies were highly specific and reacted with smooth muscle myosin but not with platelet, skeletal muscle, or cardiac muscle myosin. To evaluate comprehensively the structural profile of smooth muscle elements in normal human tissues, an indirect immunoperoxidase technique (peroxidase-antiperoxidase) was applied to a wide variety of specimens. Parallel studies comparing cryostat sections with fixed (10% formalin, B5, Bouin's, or Zenker's solution) paraffin-embedded tissues revealed optimal immunoreactivity, sensitivity, and specificity of staining for smooth muscle myosin using frozen tissues. Strong immunoreactivity was present in muscular tissues such as blood vessels and the muscularis of gastrointestinal and genitourinary tracts. Distinct delineation of smooth muscle elements, including individual smooth muscle cells, and their specific patterns of alignment and organization, were observed, e.g., cells comprising the muscularis mucosae and extending into the lamina propria of the gastrointestinal tract, and myoepithelial cells of skin, exocrine glands, and breast. This method provides excellent morphologic preservation and readily permits unambiguous identification of individual cells containing smooth muscle myosin.

Polymerized haemocyanin molecules have been identified as rings, about 25nm in diameter, forming linear arrays within cytoplasmic vesicles, close to the nucleus. They were observed by transmission electron microscopy in the polygonal cells of the branchial gland of Eledone moschata Lamarck. These observations confirm previous data suggesting that haemocyanin is synthetized in the branchial gland cells of Octopoda.

This paper summarizes a variety of quantitative data on the silkworm Bombyx mori, collected in the literature, to help building models on silk gland differentiation. The properites of the silk gland and their changes especially during the last larval instar have been reviewed (size, DNA, RNA amino acids, enzymes). The components of the silk (fibroin and sericin) are also studied (molecular weight, composition). Thus translation and transcription rates have been estimated. The relevant data on the fat body and the haemolymph are also given, as well as some characteristics of the oocyte/egg system.

The adhesive protein from Mytilus edulis contains 75-80 closely related, repeated peptide sequences in its primary structure. These peptides can be resolved following digestion with trypsin by reversed-phase high-pressure liquid chromatography. The most frequently repeated sequence is the decapeptide Ala-Lys-Pro-Ser-Tyr-Hyp-Hyp-Thr-Dopa-Lys (peptide E). Variations of this occur in peptides B with Hyp-3 and Dopa-5, C with Dopa-5, and D with Hyp-3, respectively. Lesser amounts of hexapeptides (A and B') that are lacking residues 4-7 also occur. Peptide A has the sequence Ala-Lys-Pro-Thr-Dopa-Lys, whereas B' contains Tyr instead of Dopa. 4-Hydroxyproline occurs at positions 3 and 7 and occasionally at position 6 of the decapeptide; 3-hydroxyproline occurs only at position 6. Adhesiveness of the protein may be related to the repetition of Dopa residues, the catecholic moiety of which has strong hydrogen-bonding and metal-liganding capabilities.

Nucleotide sequence of 5.8S rRNA of the silkworm, Bombyx mori has been determined by gel sequencing methods. The 5.8S rRNA was the longest so far reported, with the 5'-terminal sequence several nucleotides longer than those of the other organisms. Upon constructing the secondary structure in accordance with the "burp gun" model (12), the Bombyx 5.8S rRNA formed a wide-open "muzzle" due to several unpaired bases at the ends. The overall structure also appeared less stable with less G . C pairs and more unpaired bases than that of the HeLa 5.8S rRNA. These structural features may be essential for those 5.8S rRNAs which interact with 28S rRNAs containing the hidden break to form a stable complex.

A large scale fractionation of tRNA from the posterior silkgland of the silkworm Bombyx mori L. by countercurrent distribution is described. One single 1,500 transfer distribution carried out with Phosphate buffer-Fromamide-Isopropanol (PFI) solvent system yields highly enriched isoaccepting species with increasing mobility order: tRNA1Gly, tRNA1-2Ala, tRNATyr, tRNA2Gly, tRNA1Ser and tRNA2Ser with 75%, 70%, 90%, 60%, 60%, and 90% purities respectively. Nucleosides fingerprint analysis of each iso-tRNA species confirms the anticodon structures previously suggested for tRNA2Ala (IGC), tRNA2bGly (U-CC) (U-CC) and tRNA2bSer (IGA). Twenty two minor nucleosides, three of them with unknown structure, have been detected. They are: m5C in tRNA1Gly, m1I in all tRNAAla species, polar A and U called X in tRNATyr, polar U derivative in tRNAGly2, mt6A in tRNASer1 and i6A tRNA2Ser. Both tRNASer species have m3C and ac7C. We do not detect Q, Y and thiol derivatives. The elution characteristics of silkgland tRNA species may be expressed in a semilogarithmic diagram where log K (K is the partition coefficient) is related to the base ratio A/Y) and the coding properties. The distribution pattern of silkgland tRNAs has been compared with that of Yeast and Rat liver tRNAs fractionated by countercurrent distribution with the PFI and PMB (Potassium phosphate buffer, 2-methoxy ethanol, 2-butoxy ethanol) solvent systems.

The staining properties of secretory granules present in pancreatic duct glands and in secretory cells of pancreatic duct epithelia are studied in cat, dog, and man. The secretory material contains histochemically detectable disulfide groups and tryptophan. The mucosubstance is characterized as GC-mucin B (2.5) A (0.8 MgCl2), in part N (i.e. a sialoglycoprotein with vic-glycols, sialic acid carboxyls, being basophil at pH = 2.5, alcianophil in the presence of 0.8 M MgCl2, and in part sensitive to digestion with alpha-neuraminidase).

The enzyme gland of the foot of the mussel Mytilus has been so far considered a gland producing and exporting a phenol oxidase catalysing the general tanning processes of byssus threads. In contrast, the present study shows that this gland produces mainly secretory granules which form the cortical layers of byssus threads. Cytochemical methods at the ultrastructural level (phosphotungstic acid at low pH, silver methenamine, periodic acid-thiosemicarbazide-silver proteinate, silver methenamine for sulphur-rich proteins demonstration) and enzyme digestion tests (pepsin, trypsin, alpha-chymotrypsin) indicate that secretory granules contain glycoproteins rich in sulphydryl groups and in aromatic amino acids. The cytochemical demonstration of phenol oxidase shows that enzyme activity is present in Golgi complex, whereas it is absent in secretory granules. For this reason, phenol oxidase does not seem to be exported and utilized for tanning of byssus threads, but it might rather be involved in the elaboration and tanning of the content of the secretory granules in the enzyme gland itself.

The secretory characteristics of the glands in both the lateral nasal wall and the nasal septum of the rat have been studied with a variety of morphological and histochemical techniques. The main part of the glandular tissue in the lateral nasal wall is situated around the ostium of the maxillary sinus and can be divided in a dorsal, simple branched acinous glandular part and in a ventral, very branched tubulo-acinous glandular part.. No further morphological differences can be observed with light microscopical techniques. The glandular tissue on the nasal septum consists of a large, branched tubulo-acinous gland, occupying an extensive portion of the septum. By using various histochemical staining techniques for glycoproteins, 3 different areas can be distinguished, suggesting that the nasal glands produce different types of secretory products.