The relationship of phosphodiesterase and cyclic AMP to the process of fluid secretion in the salivary glands of the ixodid tickAmblyomma americanum

1978 ◽  
Vol 34 (8) ◽  
pp. 1030-1031 ◽  
Author(s):  
H. L. McMullen ◽  
J. R. Sauer
Keyword(s):  
Cyclic Amp ◽  
Salivary Glands ◽  
Fluid Secretion ◽  
Relationship Of ◽  
The Relationship

The Effects Of Derivatives Of Adenosine 3',5'-Monophosphate On Fluid Secretion By The Salivary Glands Of Calliphora

1973 ◽  
Vol 59 (3) ◽  
pp. 595-606
Author(s):  
M. J. BERRIDGE
Keyword(s):  
Cyclic Amp ◽  
Salivary Glands ◽  
Cyclic Nucleotides ◽  
Fluid Secretion ◽  
Receptor Interaction ◽  
Base Region ◽  
Adenine Ring ◽  
Derivatives Of ◽  
Ribose Sugar

1. The nature of the cyclic AMP-receptor interaction was analysed by testing a range of cyclic nucleotides on the isolated salivary glands of adult blowflies. 2. All compounds containing modifications in the region of ribose or the phosphate ring were inactive. One compound, adenosine 3',5'-phosphorothioate, appeared to compete with cyclic AMP. 3. A number of nucleotides with alterations restricted to the base region of the molecule could stimulate secretion equally as well as cyclic AMP. 4. These observations indicate that during the action of cyclic AMP the phosphate ring and ribose sugar are critical whereas the adenine ring plays a relatively unspecific role.

scholarly journals Complex phosphorylation activity in neurosecretosomal membranes isolated from ox neurohypophyses

1980 ◽  
Vol 188 (3) ◽  
pp. 657-666 ◽  
Author(s):  
M Treiman ◽  
S Worm-Petersen ◽  
N A Thorn
Keyword(s):  
Cyclic Amp ◽  
Gel Electrophoresis ◽  
Major Part ◽  
Sodium Dodecyl ◽  
Experimental Conditions ◽  
Pituitary Glands ◽  
Relationship Of ◽  
The Relationship ◽  
The Brain ◽  
Soluble Components

Homogenates of neural lobes of bovine pituitary glands were fractionated on Ficoll gradients to yield neurosecretosomes (nerve endings). The neurosecretosomes were lysed in a hypo-osmotic buffer and the membranes were separated from the soluble components by centrifugation. On incubation with [gamma-32P]ATP this membrane preparation showed an endogenous phosphorylation activity, which was studied by means of gel electrophoresis in the presence of sodium dodecyl sulphate, and subsequent autoradiography. The major part of the [32P]Pi detected on the gel was shown to be incorporated into three protein bands, termed A, B and C, with minimal mol.wts. of 83 000, 59 000 and 47 000 respectively. The phosphorylation of these three proteins was studied under a variety of experimental conditions. The patterns obtained were partly similar. However, important individual differences were noted, particularly with respect to the effects of cyclic AMP, Mg2+ and Ca2+. On the basis of these differences, it is suggested that in this system the phosphorylation activity is heterogenous, bands A, B and C each reflecting the presence of a different site of phosphate turnover. The relationship of bands A, B and C to several of the previously described phosphoproteins in the brain is discussed.

scholarly journals MEDIATION OF IMMUNOLOGIC DISCHARGE OF LYSOSOMAL ENZYMES FROM HUMAN NEUTROPHILS BY GUANOSINE 3',5'-MONOPHOSPHATE

1974 ◽  
Vol 140 (1) ◽  
pp. 225-238 ◽  
Author(s):  
L. J. Ignarro ◽  
W. J. George
Keyword(s):  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Lysosomal Enzymes ◽  
Extracellular Calcium ◽  
Human Neutrophils ◽  
Enzyme Release ◽  
Dibutyryl Cyclic Amp ◽  
Relationship Of ◽  
The Relationship ◽  
Stimulation Of

The purpose of this investigation was to elucidate the relationship of cyclic GMP and calcium to the immunologic discharge of lysosomal enzymes from purified human neutrophils. Contact of neutrophils with a variety of immunologic stimuli, including zymosan particles treated with either normal or rheumatoid arthritic (RA) serum, heat-aggregated (agg) IgG, particulate and immobilized agg IgG each treated with RA serum, and zymosan-treated serum, provoked the discharge of ß-glucuronidase, but not cytoplasmic lactate dehydrogenase, and stimulated the accumulation of cyclic GMP. Both enzyme release and elevation of cyclic GMP levels required the presence of extracellular calcium as neither cellular event proceeded in its absence. Cholinergic enhancement of the immunologic secretion of ß-glucuronidase from neutrophils by acetylcholine was associated with a concomitant accumulation of cyclic GMP. These actions of acetylcholine on neutrophils did not proceed in the absence of extracellular calcium. Whereas the concentrations of cyclic GMP in neutrophils were elevated by both immune reactants and a combination of the latter and acetylcholine, cyclic AMP levels remained unaltered. Thus, cyclic GMP, but not cyclic AMP, was associated with the immunologic and pharmacologic discharge of lysosomal enzymes from neutrophils. Contrariwise, cyclic AMP, but not cyclic GMP, was associated with inhibition of lysosomal enzyme release. For example, dibutyryl cyclic AMP and epinephrine inhibited the release of ß-glucuronidase from neutrophils that was elicited by each of the immune reactants tested. Moreover, cyclic AMP levels in the cells were elevated markedly in every instance that enzyme discharge was inhibited by epinephrine. Epinephrine did not alter the neutrophil concentrations of cyclic GMP at times when those of cyclic AMP were elevated. The data in this report constitute partial evidence that the immunologic discharge of lysosomal enzymes from human neutrophils is mediated or signaled by intracellular cyclic GMP and that calcium is linked to this stimulation of enzyme secretion.

Changes in Calcium Transport across Calliphora Salivary Glands Induced by 5-Hydroxytryptamine and Cyclic Nucleotides

1979 ◽  
Vol 78 (1) ◽  
pp. 137-148
Author(s):  
MICHAEL J. BERRIDGE ◽  
HERBERT LIPKE
Keyword(s):  
Cyclic Amp ◽  
Salivary Glands ◽  
Calcium Transport ◽  
Fluid Secretion ◽  
Ionophore A23187 ◽  
Active Calcium ◽  
University Of Massachusetts ◽  
Dependent Transport ◽  
The University ◽  
Internal Calcium

The efflux of 45Ca from prelabelled salivary glands was studied under a variety of conditions. 5-Hydroxytryptamine (5-HT) or cyclic AMP caused a large release of label most of which entered the saliva. The ionophore A23187 caused a similar release of calcium but EGTA had no effect. The presence of an active calcium pump on the lumenal surface was investigated further by studying calcium transport across the gland. This transport of calcium, which provides a measure of calcium entry into the cell, was very sensitive to 5-HT concentration but little affected by cyclic AMP. The small cyclic AMP-dependent transport was depressed by 8-bromo cyclic GMP with a parallel fall in the rate of fluid secretion. These studies provide more direct evidence that 5-HT acts to stimulate the entry of external calcium in addition to mobilizing internal calcium. Note: On sabbatical leave from the University of Massachusetts, Boston.

The electrical response of isolated salivary glands during stimulation with 5-hydroxytryptamine and cyclic AMP

1971 ◽  
Vol 262 (842) ◽  
pp. 111-120 ◽  
Keyword(s):  
Cyclic Amp ◽  
Salivary Glands ◽  
Electrical Response ◽  
Liquid Paraffin ◽  
Fluid Secretion ◽  
Positive Potential ◽  
Bathing Medium ◽  
Gap Technique ◽  
Rapid Changes ◽  
Continuous Potential

Rate of fluid secretion by the salivary glands of the blowfly Calliphora is regulated by 5-hydroxytryptamine (5-HT) working in conjunction with cyclic AMP. Although cyclic AMP can exactly mimic the acceleration of fluid secretion produced by 5-HT, the underlying electrical events are completely different. Transepithelial potentials were measured by a liquid paraffin-gap technique which permits continuous potential recordings during rapid changes of the bathing medium. The potential of the lumen of unstimulated glands is + 5 mV with respect to the bathing medium but becomes — 10 to 20 mV after applying 5-HT. After stimulation with cyclic AMP, however, the luminal potential becomes more positive (+ 30 to 40 mV). A similar effect is obtained with theophylline or when glands are treated with 5-HT in the presence of an impermeant anion such as isethionate. These observations suggest that in addition to stimulating the synthesis of cyclic AMP, 5-HT may also act directly to increase anion movement. Cyclic AMP appears to stimulate cation transport, which explains the increase in positive potential obtained when this compound (or theophylline) is applied in the absence of 5-HT.

Computed Tomography of the Submandibular Salivary Glands

1987 ◽  
Vol 28 (6) ◽  
pp. 693-696 ◽  
Author(s):  
S. G. Larsson ◽  
R. B. Lufkin ◽  
L. A. Hoover
Keyword(s):  
Computed Tomography ◽  
Salivary Glands ◽  
Normal Subjects ◽  
Normal Group ◽  
Platysma Muscle ◽  
Submandibular Duct ◽  
Submandibular Salivary Glands ◽  
Specific Finding ◽  
Relationship Of ◽  
The Relationship

Computed tomography offers a convenient method for the evaluation of the submandibular salivary glands and their surroundings. Normal measurements were established based on 38 normal subjects. The visualization of the ductal system in the gland and the relationship of the gland to the platysma muscle were recorded. The CT scans of 12 patients with a tongue base carcinoma and 4 patients with a verified obstruction of the submandibular duct were also reviewed to establish how the glands are affected by extrinsic lesions. The normal glands measured 28×18 mm (±5 mm) in the axial plane. Two patients with unilateral hypoplasia of the gland were found in the normal group. Visualization of the intraglandular duct is not a specific finding since it was observed in more than 25 per cent of the normal group. Displacement and bulging of the platysma muscle by the submandibular gland can be a sign of glandular enlargement. It was also seen in 9 out of 12 patients with carcinoma of the base of the tongue.

The Role of 5-Hydroxytryptamine and Cyclic AMP in the Control of Fluid Secretion by Isolated Salivary Glands

1970 ◽  
Vol 53 (1) ◽  
pp. 171-186 ◽  
Author(s):  
M. J. BERRIDGE
Keyword(s):  
Amino Acids ◽  
Cyclic Amp ◽  
Salivary Glands ◽  
Mode Of Action ◽  
Recovery Time ◽  
Fluid Secretion ◽  
Control Fluid ◽  
Hydrolysis Of ◽  
Derivatives Of

1. Isolated salivary glands of Calliphora have been used as a system on which to study the mode of action of a hormone. 2. Cyclic AMP, which is thought to mediate the action of many different hormones, can stimulate fluid secretion equally as well as 5-HT. 3. Methyl xanthines, which inhibit the hydrolysis of intracellular cyclic AMP by phosphodiesterase, can stimulate secretion and prolong recovery time after removal of 5-HT. 4. Methyl xanthines can sensitize salivary glands to both 5-HT and cyclic AMP. 5. Butyryl derivatives of cyclic AMP can stimulate secretion, but their effect is slower and lasts longer. 6. Certain amino acids and malate support fluid secretion more effectively than trehalose or glucose. 7. It is concluded that cyclic AMP plays an important role in the ability of 5-HT to control fluid secretion by salivary glands.

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