Novel exocrine glands in the hindleg tarsi of the ant Nothomyrmecia macrops

2000 ◽  
Vol 48 (6) ◽  
pp. 661 ◽  
Author(s):  
Johan Billen ◽  
Fuminori Ito ◽  
Christian Peeters
Keyword(s):  
Golgi Apparatus ◽  
Secretory Cell ◽  
Anterior Part ◽  
Duct Cell ◽  
Exocrine Gland ◽  
Secretory Cells ◽  
Exocrine Glands ◽  
The Third ◽  
Duct Cells

The third tarsomere of the hindlegs of both workers and queens of Nothomyrmecia macrops is almost entirely filled with a hitherto unknown exocrine gland (which does not occur in the closely related Myrmecia). Each of the approximately 30 secretory cells is connected to the outside via a duct cell. These open individually via large cuticular pores at the mesoventral side of the anterior part of the tarsomere. The diameter of the duct cells is narrow near the secretory cell, but gradually increases towards their opening site. The rounded secretory cells show a well developed Golgi apparatus and numerous clear vesicles. The function of this gland is not yet known, although its opening site may be indicative of the deposition of marking substances. At the mediodistal side of tarsomeres 2, 3 and 4 in the three pairs of legs, a glandular thickening of the epidermal epithelium occurs; this represents another novel exocrine structure in ants. This epithelial gland occurs in both Nothomyrmecia and Myrmecia.

Anatomy, ultrastructure, and functional morphology of the metathoracic tracheal defensive glands of the grasshopper Romalea guttata

1991 ◽  
Vol 69 (8) ◽  
pp. 2100-2108 ◽  
Author(s):  
Douglas W. Whitman ◽  
Johan P. J. Billen ◽  
David Alsop ◽  
Murray S. Blum
Keyword(s):  
Secretory Cell ◽  
Tactile Stimulation ◽  
Defensive Secretion ◽  
Smooth Endoplasmic Reticulum ◽  
Duct Cell ◽  
Secretory Cells ◽  
Glandular Tissue ◽  
Golgi Bodies ◽  
Romalea Guttata ◽  
Defensive Glands

In the lubber grasshopper Romalea guttata, the respiratory system produces, stores, and delivers a phenolic defensive secretion. The exudate is secreted by a glandular epithelium surrounding the metathoracic spiracular tracheal trunks. Embedded in the glandular tissue are multiple secretory units, each comprised of a basal secretory cell and an apical duct cell. Secretory cells have numerous mitochondria, a tubular, smooth endoplasmic reticulum, well-developed Golgi bodies, and a microvillilined vesicle thought to transfer secretion to the intracellular cuticular duct of a duct cell. Ducts empty into the metathoracic tracheal lumina where the exudate is stored behind the closed metathoracic spiracle. Tactile stimulation elicits secretion discharge, which begins when all spiracles except the metathoracic pair are closed and the abdomen is compressed. Increased hemostatic and pneumatic pressures drive air and secretion out of the spiracle with an audible hiss. Both metathoracic spiracles discharge simultaneously. The secretion erupts first as a dispersant spray, then as an adherent froth, and finally assumes the form of a slowly evaporating repellent droplet. Discharge force and number vary with eliciting stimuli, volume of stored secretion, and age, disturbance state, and temperature of the insect. Molting grasshoppers are unable to discharge because the stored exudate is lost with the shed cuticle. The advantages and limitations of a tracheal defensive system are discussed.

The fine structure of Verson's glands in molting larvae of Calpodes ethlius (Hesperiidae, Lepidoptera)

1973 ◽  
Vol 51 (11) ◽  
pp. 1201-1210 ◽  
Author(s):  
Joan Lai-Fook
Keyword(s):  
Fine Structure ◽  
Secretory Cell ◽  
Duct Cell ◽  
Secretory Cells ◽  
Dense Granules ◽  
Cell Processes ◽  
Residual Bodies

The three cells which make up Verson's glands in Calpodes undergo drastic changes as they produce the cuticular linings and the secretions of the glands. The duct cell secretes only the typical cuticular duct. The saccule cell produces both the atypical cuticular saccule and dense granules which are discharged just before ecdysis. The secretory cell is much enlarged by vacuoles which remain separate until they too are discharged before ecdysis. Dense granules are also produced by the secretory cell. During deposition of the cuticular duct and saccule, their lumina arc packed with cell processes containing microtubules, which appear to arise from centrioles. Isolation and residual bodies appear in both the saccule and secretory cells even before discharge of their secretions.

Different physiological signatures of sweat gland secretory and duct cells in culture

1988 ◽  
Vol 255 (1) ◽  
pp. C102-C111 ◽  
Author(s):  
C. J. Jones ◽  
C. L. Bell ◽  
P. M. Quinton
Keyword(s):  
Sweat Gland ◽  
Duct Cell ◽  
Eccrine Sweat Gland ◽  
Secretory Cells ◽  
Bathing Medium ◽  
Cholinergic Agonist ◽  
Beta Adrenoceptor ◽  
Duct Cells ◽  
Adrenoceptor Agonist ◽  
Hyperpolarizing Response

Human eccrine sweat gland cells grown in culture were found to lose their characteristic shape, becoming flattened and organized into multilayers. The resting membrane potentials of the cultured secretory cells (-35 +/- 2 mV, n = 36) were significantly higher than those measured for cultured duct cells (-22 +/- 1 mV, n = 58, P less than or equal to 0.01). When the cholinergic agonist methacholine (10(-5) or 10(-6) M) was administered, the cultured secretory cells could be distinguished unequivocally by their atropine-sensitive hyperpolarizing response (-20 +/- 2 mV, n = 43), whereas no cultured duct cells responded. When the sodium conductance antagonist amiloride (10(-5) or 10(-6) M) was administered, 44% of cultured secretory cells responded by hyperpolarization (-8 +/- 1 mV, n = 8), whereas 87% of cultured duct cells hyperpolarized (-15 +/- 1 mV, n = 46) and by a significantly greater margin (P less than or equal to 0.01). Substitution of chloride with gluconate in the bathing medium caused membrane potential depolarization in both cultured secretory and duct cell populations, which is consistent with the presence of a chloride conductance in the plasma membrane. The beta-adrenoceptor agonist isoproterenol induced a transient hyperpolarization of 5-10 mV in three out of six cultured secretory cells tested but had no effect on cultured duct cells.

scholarly journals Localization of the G-protein G(o) in exocrine glands.

1994 ◽  
Vol 42 (1) ◽  
pp. 41-47 ◽  
Author(s):  
E L Watson ◽  
C Oliver ◽  
N D'Silva ◽  
C M Belton
Keyword(s):  
Parotid Gland ◽  
G Protein ◽  
Acinar Cells ◽  
Duct Cell ◽  
Protein G ◽  
Cell Physiology ◽  
Exocrine Glands ◽  
Duct Cells ◽  
Rat Parotid Gland ◽  
Rat Parotid

The GTP-binding protein G(o) was localized immunohistochemically in the rat parotid gland and in other exocrine glands with specific G(o) antibodies. Immunohistochemical studies revealed that affinity-purified G(o alpha) polyclonal antibody (GO/85) immunoreacted primarily with duct cells of the rat parotid gland; immunoreactivity was also noted in duct cells of the rat submandibular, mouse parotid, and mouse submandibular glands. Light labeling of rat parotid and submandibular gland acinar cells was also noted. G(o alpha) antiserum (9072) differing in specificity for epitopes within G(o alpha) produced similar results. This antiserum also immunoreacted with rat submandibular duct cell secretory granule membranes. In contrast, in rat and mouse pancreas G(o alpha) antibodies immunoreacted primarily with islet cells. Duct cells were negative but there was light labeling of rat pancreatic acinar cells. The apparent duct specificity of G(o alpha) staining was further verified by demonstrating that G(o alpha) antibodies immunoreacted with HSG-PA cells, a human transformed salivary duct cell line. Specificity in immunohistochemical labeling of HSG-PA cells was confirmed by Western blot analysis. The results demonstrate that G(o) appears to be selectively expressed in the duct cells of rat parotid gland and other salivary glands. The selective enrichment of G(o) in duct cells suggests that this G-protein plays an important role in duct cell physiology.

Biogenesis of Catalase-Positive Rods in Excretory Duct Cells of Salivary Glands

1976 ◽  
Vol 34 ◽  
pp. 62-63
Author(s):  
Dwight K. Romanovicz ◽  
Jacob S. Hanker
Keyword(s):  
Light Microscopy ◽  
Salivary Glands ◽  
Submandibular Gland ◽  
Excretory Duct ◽  
Exocrine Glands ◽  
Duct Cells ◽  
Peroxidatic Activity ◽  
Microscopic Studies ◽  
Different Dimensions

The presence of catalase-positive rods (Fig. 1) of different dimensions, which frequently have a crystalline appearance by light microscopy, has been reported. They seem to be related to peroxisomes which were characterized morphologically and cytochemically in parotid and other exocrine glands of the rat by Hand in 1973. Our light microscopic studies of these spherical microbodies and rods of different sizes, stained by virtue of the peroxidatic activity of their catalase, indicate that they are almost entirely confined to the cells of the striated and execretory ducts of the submandibular gland in the mouse. The rods were usually noted only in the proximity of the ductal microbodies. The latter frequently showed a tendency to appear in linear close array, or even to be contiguous (Fig. 2). This suggested that the rods could be formed by the fusion of microbodies.

Sensitivity of mammary secretory cell turnover to protein restriction and re-alimentation during early lactation

1997 ◽  
Vol 1997 ◽  
pp. 130-130
Author(s):  
M.G. Goodwill ◽  
N.S. Jessop ◽  
J.D. Oldham
Keyword(s):  
Cell Proliferation ◽  
Mammary Gland ◽  
Milk Production ◽  
Secretory Cell ◽  
Protein Restriction ◽  
Secretory Cells ◽  
Early Lactation ◽  
Cell Turnover ◽  
Lactational Performance

Milk production depends on both the number and activity of secretory cells within the mammary gland. Our earlier work showed the sensitivity of lactational performance to changes in diet during lactation (Goodwill et al, 1996). This study investigated the influence of protein undernutrition and re-alimentation on secretory cell proliferation and death in the mammary gland of rats during early lactation.

The effect of embryonic partial decapitation on the developmental sequence of some proteins in the chicken

Development ◽  
1966 ◽  
Vol 16 (1) ◽  
pp. 83-89
Author(s):  
Clyde Manwell ◽  
T. W. Betz
Keyword(s):  
Pituitary Gland ◽  
Anterior Part ◽  
Hormonal Control ◽  
Hormone Action ◽  
Developmental Sequence ◽  
In Ovo ◽  
Developmental System ◽  
The Third ◽  
Insect Metamorphosis ◽  
Biochemical Level

Hormonal control of differentiation at a biochemical level is exemplified by studies on amphibian and insect metamorphosis. However, Hinni & Watterson (1963) have reviewed the literature and presented new data on another developmental system with potential for analysis of hormone action. Chicken embryos at 33–36 h of incubation can be ‘hypophysectomized’ by partial decapitation, the prosencephalic and anterior part of the mesencephalic areas being removed. Absence of the pituitary primordium prevents the formation of a pituitary gland. Such embryos that continue to develop are noticeably smaller and show retardation in the development of bones, feathering, and several epithelial structures by 2 weeks of incubation. These ‘hypophysectomized’ embryos have an increased mortality, especially in the third week of incubation; the few that escape this ‘phenocritical period’ never hatch and remain in ovo days after the normal time of hatching.

Describing the lactation curve of dairy animals

1999 ◽  
Vol 1999 ◽  
pp. 197-197 ◽  
Author(s):  
G. E. Pollott
Keyword(s):  
Secretory Cell ◽  
Empirical Models ◽  
Secretory Cells ◽  
Cell Numbers ◽  
Biological Meaning ◽  
Lactation Curve ◽  
Dairy Animals ◽  
The Difference ◽  
Daily Milk Yield ◽  
Daily Milk

Most functions used to describe the lactation curve of dairy animals are empirical in approach and result in parameters with little or no biological meaning. A new model for describing lactation based on the biology of the pregnant and lactating animal is proposed and compared to several empirical models (Wood, 1967; Grossman and Koops, 1988; Morant and Gnanasakthy, 1989).Lactation is thought of as the balance between an increase in secretory cell numbers (NSCP) and their later decline (NSCD). The difference between them is the number of active secretory cells, each of which secretes milk at a particular rate (S kg/cell/day). Thus daily milk yield (MY) = (NSCP – NSCD) x S.

Vasopressin in blood and third ventricle CSF of dogs in chronic experiments

1983 ◽  
Vol 245 (4) ◽  
pp. R541-R548 ◽  
Author(s):  
C. Simon-Oppermann ◽  
D. Gray ◽  
E. Szczepanska-Sadowska ◽  
E. Simon
Keyword(s):  
Cerebrospinal Fluid ◽  
Arginine Vasopressin ◽  
Anterior Part ◽  
Third Ventricle ◽  
Conscious State ◽  
Conscious Dogs ◽  
Inhalation Anesthesia ◽  
Blood Samples ◽  
The Third ◽  
Device Implantation

A device for chronic implantation was developed that allowed sampling of cerebrospinal fluid (CSF) from the anterior part of the third cerebral ventricle (A3V) of dogs in repeated experiments for up to 4 mo. Osmolalities, electrolyte concentrations, and concentrations of arginine vasopressin (AVP) measured with a radioimmunoassay were determined in repeated experiments on the chronically prepared animals under conditions of normal hydration, both in the conscious state and during inhalation anesthesia. In conscious dogs, AVP concentrations in plasma and CSF were 3.3 +/- 0.4 and 21.8 +/- 2.5 pg X ml-1, respectively. During anesthesia without surgical interference, the AVP concentrations in plasma and CSF were increased twofold above the levels obtained in conscious dogs. During the time of observation (180 min) all measured parameters remained constant. The AVP concentrations in plasma and CSF samples collected during the surgical procedure of device implantation were about 10-fold higher than in the samples collected during the conscious state. Thus, in each experimental condition, AVP concentration in the CSF collected from the A3V was consistently higher than that in the simultaneously collected blood samples.

scholarly journals Knockdown of p180 Eliminates the Terminal Differentiation of a Secretory Cell Line

2009 ◽  
Vol 20 (2) ◽  
pp. 732-744 ◽  
Author(s):  
Payam Benyamini ◽  
Paul Webster ◽  
David I. Meyer
Keyword(s):  
Cell Line ◽  
Mammalian Cells ◽  
Secretory Cell ◽  
Terminal Differentiation ◽  
Secretory Cells ◽  
Rnai Technology ◽  
Apo E ◽  
Secretory Phenotype ◽  
Rough Er ◽  
Necessary And Sufficient

We have previously reported that the expression in yeast of an integral membrane protein (p180) of the endoplasmic reticulum (ER), isolated for its ability to mediate ribosome binding, is capable of inducing new membrane biogenesis and an increase in secretory capacity. To demonstrate that p180 is necessary and sufficient for terminal differentiation and acquisition of a secretory phenotype in mammalian cells, we studied the differentiation of a secretory cell line where p180 levels had been significantly reduced using RNAi technology and by transiently expressing p180 in nonsecretory cells. A human monocytic (THP-1) cell line, that can acquire macrophage-like properties, failed to proliferate rough ER when p180 levels were lowered. The Golgi compartment and the secretion of apolipoprotein E (Apo E) were dramatically affected in cells expressing reduced p180 levels. On the other hand, expression of p180 in a human embryonic kidney nonsecretory cell line (HEK293) showed a significant increase in proliferation of rough ER membranes and Golgi complexes. The results obtained from knockdown and overexpression experiments demonstrate that p180 is both necessary and sufficient to induce a secretory phenotype in mammalian cells. These findings support a central role for p180 in the terminal differentiation of secretory cells and tissues.

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