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Query: UMLS:C0043167 (
pertussis
)
19,595
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Administration of adenosine (Ado) into rat renal artery induces dose-dependent diuresis that is independent of changes in glomerular filtration rate or renal blood flow, suggesting a direct effect on tubule
H2O
reabsorption. To test the hypothesis that Ado modulates cellular action of arginine vasopressin (AVP) as a tubular mechanism for the diuretic effect of Ado, interaction of Ado with AVP was studied in primary cell culture of rat inner medullary collecting duct (IMCD) epithelium. Stimulation of cells with 10(-6) M AVP in presence of 0.1 mM Ro 20-1724, a nonmethylxanthine phosphodiesterase inhibitor that has no effect on Ado receptors, increased adenosine 3',5'-cyclic monophosphate (cAMP) levels twofold or more above baseline. Stimulation of cells with the A1 Ado-receptor agonist N6-cyclohexyladenosine (CHA), the A2-receptor agonist 5'-(N-ethylcarboxamido)-adenosine (NECA), or with the P-site agonist 2',5'-dideoxyadenosine (DDA) significantly inhibited the AVP-stimulated cAMP response. Preincubation with
pertussis
toxin abolished the inhibitory effects of CHA and NECA, but not of DDA. The data suggest that, in the rat IMCD, Ado modulates AVP action by interfering with its ability to stimulate formation of its second messenger, cAMP. This effect is mediated by the extracellular Ado receptors A1 and A2 and by the intracellular P-site. It occurs by at least two pathways, one sensitive and the other insensitive to
pertussis
toxin.
...
PMID:Interaction of adenosine with vasopressin in the inner medullary collecting duct. 217 61
The amounts of endotoxin in commercial blood products were measured by the turbidimetric kinetic Limulus test with an ordinary reagent (LAL-HS) and a new endotoxin-specific reagent (LAL-ES). LAL-ES contains a sufficient amount of a
water
-soluble (1----3)-beta-D-glucan derivative as a blocker of the (1----3)-beta-D-glucan-mediated coagulation pathway in the reaction of the Limulus amebocyte lysate. The amounts of endotoxin in albumin and globulin products measured with LAL-ES agreed with pyrogenic activities in rabbits, but those measured with LAL-HS did not. Added endotoxin in the blood products was well recovered with LAL-ES, but that in some products was excessively recovered with LAL-HS. The amounts of endotoxin in diphtheria-
pertussis
-tetanus combined vaccines measured with LAL-HS and LAL-ES agreed with the pyrogenic activities in rabbits. The results suggested the existence of a false-positive substance like beta-glucan in the blood products but not in the vaccine. LAL-ES is more suitable for the detection of endotoxin in blood products than LAL-HS.
...
PMID:[Measurement of endotoxin in blood products using an endotoxin-specific Limulus test reagent and its relation to pyrogenic activities in rabbit]. 237 24
The nature of the leukotriene-D4 (LTD4) induced cell shrinkage in Ehrlich ascites tumor cells has been investigated. LTD4 treatment of Ehrlich cells induces net loss of cellular KCl and cell shrinkage independent of the initial cell volume. LTD4 also produces
water
loss and reduction in cell volume when all extracellular and all intracellular Cl has been replaced by NO3. On the other hand, LTD4 fails to produce any significant changes in cell volume in the presence of the K-channel blocker quinine, suggesting that LTD4 in Ehrlich cells induces Cl-independent K loss through the Ca2+-dependent K channels. However, the effect of physiological doses of LTD4 on cell volume seems not to be as potent in Cl-free, NO3 cells when compared to Cl-containing cells, indicating that LTD4 in Ehrlich cells also provokes Cl-dependent K loss. LTD4 seems not to produce K loss through an electroneutral K+/H+ exchange system. LTD4 still produces Cl-independent K loss and cell shrinkage in the presence of the anti-calmodulin drug pimozide but not in the presence of the LTD4 receptor antagonist L-649,923 or the 5-lipoxygenase inhibitor NDGA. Pretreatment of the cells with
pertussis
toxin, which inactivates inhibitory guanine nucleotide binding proteins (G-proteins), leads to partial inhibition of the LTD4-induced shrinkage. It is suggested that the LTD4-induced activation of K and Cl transporting systems in Ehrlich ascites tumor cells is mediated via a G-protein coupled receptor and that LTD4 might exert its effect through another lipoxygenase product. The Ca2+-calmodulin complex is not involved in the LTD4-induced activation of K and Cl transporting systems.
...
PMID:Leukotriene-D4 induced cell shrinkage in Ehrlich ascites tumor cells. 247 62
Forskolin inhibited cyclic AMP generation in J774 macrophage cells in response to isoproterenol. Forskolin, 10 nM-0.1 mM, also inhibited the adenylate cyclase activity of membrane preparations. The basal activity and the isoproterenol-, cholera toxin-, fluoride- or GppNHp-stimulated activities were maximally depressed by 10 microM forskolin (30-70% inhibition, EC50 = 0.3-0.5 microM). This effect was achieved similarly in membranes from
pertussis
toxin-treated cells. Forskolin required guanine nucleotides for inhibition. In the absence of GTP the decrease in basal activity was reversed into stimulation (EC50 = 10 microM forskolin). Reversal of inhibition into activation also followed the addition of 1 mM MnCl2 (EC50 = 10 microM forskolin). 1,9-Dideoxyforskolin was ineffective to alter adenylate cyclase activity. In contrast, a
water
-soluble derivative of forskolin was as active as forskolin to regulate activity. The results suggest that forskolin may interact with adenylate cyclase to cause either activation or inhibition depending on the degree of activation of Ns and on its interaction with the catalyst.
...
PMID:Forskolin inhibition of cyclic AMP generation in J774 macrophages. 255 9
Bradykinin inhibits vasopressin-stimulated
water
transport in cortical collecting tubular cells. The biochemical mechanism of this effect was explored by means of primary cultures of rabbit cortical collecting tubular cells. Bradykinin was found to produce a rapid release of calcium from intracellular stores, an increase in sn-1,2-diacylglycerol levels, and a fivefold increase in membrane-bound protein kinase C activity, consistent with stimulation of phospholipase C and activation of protein kinase C in rabbit cortical collecting tubular cells. In addition, bradykinin produced a dose-dependent 46% inhibition of vasopressin-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) formation. Pretreatment with the protein kinase C inhibitors, H-7 and staurosporine, reversed the bradykinin-mediated inhibition of vasopressin-stimulated cAMP accumulation. In contrast, pretreatment with either the phospholipase A2 inhibitor, mepacrine, or
pertussis
toxin did not prevent the inhibitory effect of bradykinin on vasopressin-stimulated cAMP production, suggesting that the effects are not mediated by prostaglandin E2 or activation of a
pertussis
-toxin sensitive guanine nucleotide regulatory protein (e.g., Gi). Because bradykinin also inhibits isoproterenol-stimulated cAMP formation but does not inhibit either basal-, forskolin-, or cholera toxin-stimulated cAMP accumulation, the site of this inhibition appears to involve the hormone receptor or coupling of the receptor to the stimulatory guanine nucleotide regulatory subunit (Gs). The results demonstrate that bradykinin stimulates phospholipase C leading to activation of protein kinase C, which then inhibits vasopressin-stimulated cAMP production at the level of the hormone receptor or coupling of the receptor to Gs in cultured cortical collecting tubular cells.
...
PMID:Bradykinin activates protein kinase C in cultured cortical collecting tubular cells. 255 39
The adrenergic nervous system profoundly alters
water
excretion by both renal and extrarenal pathways. The effects of catecholamines on cultured rat inner medullary collecting tubule cells were studied. The beta-adrenergic agonist, isoproterenol, increases cAMP from 19.5 +/- 2.3 to 79.4 +/- 14.4 fm/micrograms protein, P less than 0.001. The response to arginine vasopressin (AVP) is also greater in the presence of isoproterenol, but the increment is unchanged when compared to that seen in the absence of AVP. The agonist effect of isoproterenol is blocked by propranolol but not by the specific beta 1 antagonist, atenolol. The effect of alpha-adrenergic stimulation was studied by the use of norepinephrine (NE) in the background of the beta blocker, propranolol. NE decreases AVP-stimulated cAMP generation from 190 +/- 11 to 117 +/- 10 fm/micrograms, P less than 0.001, N = 6. The specific alpha 2 antagonist, yohimbine, but not the alpha 1 antagonist, prazosin, prevents the NE-induced decrease as AVP-stimulated cAMP is restored to 187 +/- 19 fm/micrograms. Similarly the selective alpha 2 agonist, clonidine, significantly inhibits both AVP- and isoproterenol-mediated cAMP generation. To define the site of alpha 2 inhibition in the adenylate cyclase (AC) complex the effect of
pertussis
toxin (PT) was investigated. After pretreatment with PT (1-1000 ng/ml), AVP-stimulated cAMP was not inhibited by NE. The alpha 1 agonist, phenylephrine, fails to inhibit AC or to increase cytosolic Ca in these cells.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Adrenergic control of cAMP generation in rat inner medullary collecting tubule cells. 256 11
Prostaglandin E1 (PGE1) at 1 nM inhibits arginine-vasopressin (AVP)-induced
water
reabsorption in the rabbit cortical collecting tubule (RCCT), while 100 nM PGE1, by itself, stimulates
water
reabsorption (Grantham, J. J., and Orloff, J. (1968) J. Clin. Invest. 47, 1154-1161). To investigate the basis for these two responses, we measured the effects of prostaglandins on cAMP metabolism in purified RCCT cells. In freshly isolated cells, PGE2, PGE1, and 16,16-dimethyl-PGE2 acting at high concentrations (0.1-10 microM) stimulated cAMP accumulation; however, one PGE2 analog, sulprostone (16-phenoxy-17,18,19,20-tetranor-PGE2 methylsulfonilamide), failed to stimulate cAMP accumulation or to antagonize PGE2-induced cAMP formation; PGD2, PGF2 alpha, and a PGI2 analog, carbacyclin (6-carbaprostaglandin I2), also failed to stimulate cAMP synthesis. These results suggest that there is a PGE-specific stimulatory receptor in RCCT cells which mediates activation of adenylate cyclase. Occupancy of this receptor would be anticipated to cause
water
reabsorption by the collecting tubule. At lower concentrations (0.1-100 nM) PGE2, PGE1, 16,16-dimethyl-PGE2, and, in addition, sulprostone inhibited AVP-induced cAMP accumulation by fresh RCCT cells in the presence of cAMP phosphodiesterase inhibitors.
Pertussis
toxin pretreatment of RCCT cells blocked the ability of both PGE2 and sulprostone to inhibit AVP-induced cAMP accumulation. In membranes prepared from RCCT cells, sulprostone prevented stimulation of adenylate cyclase by AVP. These results suggest that E-series prostaglandins (including sulprostone) can act through an inhibitory PGE receptor(s) coupled to the inhibitory guanine nucleotide regulatory protein, Gi, to block AVP-induced cAMP synthesis by RCCT cells. Occupancy of this receptor would be expected to cause inhibition of AVP-induced
water
reabsorption in the intact tubule. Curiously, after RCCT cells were cultured for 5-7 days, PGE2 no longer inhibited AVP-induced cAMP accumulation, but PGE2 by itself could still stimulate cAMP accumulation. In contrast to PGE2, epinephrine acting via an alpha 2-adrenergic, Gi-linked mechanism did block AVP-induced cAMP formation by cultured RCCT cells. This implies that some component of the inhibitory PGE response other than Gi is lost when RCCT cells are cultured.
...
PMID:Regulation of cyclic AMP metabolism in rabbit cortical collecting tubule cells by prostaglandins. 283 64
Vasopressin (AVP) plays a key role in maximal urine concentration by stimulating NaCl reabsorption in the medullary thick ascending limbs of Henle (MAL) and by increasing
water
permeability in the medullary collecting tubules (MCT). These effects of AVP in MAL and MCT are mediated by cAMP. Alpha 2-adrenergic stimulation in MCT, and high ambient Ca2+ and PGE2 in MAL inhibit AVP-dependent cAMP production and thereby modulate urine concentration. The present study was undertaken to clarify the mechanisms underlying the inhibition of AVP-dependent cAMP production by these agents using microdissected mouse MAL and MCT. Preincubation of MCT and MAL with 1 microgram/ml
pertussis
toxin for 3 and 6 h, respectively, resulted in ADP-ribosylation of an approximately 41-kD protein, which was presumably an alpha subunit of the inhibitory GTP-binding protein Gi. Epinephrine, 10(-6) M, via alpha 2-adrenergic stimulation, inhibited AVP-dependent cAMP production in MCT. Preincubation of MCT for 3 h with
pertussis
toxin abolished the inhibition of AVP-dependent cAMP production by epinephrine. High ambient Ca2+ and PGE2 both inhibited AVP-dependent cAMP production in MAL. Preincubation of MAL for 6 h with
pertussis
toxin abolished the inhibition by high ambient Ca2+ and attenuated the inhibition by PGE2. Preincubation of MCT or MAL with
pertussis
toxin for 1 h was ineffective in ADP-ribosylation and did not modify the inhibition of AVP-dependent cAMP production by these agents in both nephron segments. Our data suggest that the inhibition of AVP-dependent cAMP production by alpha 2-adrenergic stimulation in MCT, and by high ambient Ca2+ and adrenergic stimulation in MCT, and by high ambient Ca2+ and PGE2 in MAL, is mediated, at least in part, through activation of Gi.
...
PMID:Inhibitory guanosine triphosphate-binding protein-mediated regulation of vasopressin action in isolated single medullary tubules of mouse kidney. 284 57
Free lipid A of Bordetella
pertussis
, Neisseria meningitidis, and Escherichia coli lipopolysaccharide (LPS) was prepared by hydrolysis in acetate buffer (pH 4.5); in addition, lipid A from B.
pertussis
and E. coli was prepared by hydrolysis in mineral acid (HCl). The precipitates obtained were purified by extraction methods in toluene-methanol and are referred to as crude lipid A. Purified lipid A from N. meningitidis and B.
pertussis
was obtained by extraction in a mixture of chloroform-methanol-
water
-triethylamine. The different preparations were tested for their pyrogenicity (endogenous pyrogen; EP) and their capacity to trigger the release of interleukin-1 (IL-1; previously known as lymphocyte-activating factor; LAF) by human monocytes. Crude lipid A from E. coli and N. meningitidis were both IL-1 inducers. Crude B.
pertussis
lipid A (acetate buffer; pH 4.5), which contains a beta-1-6-linked D-glucosamine disaccharide, two phosphoryl groups, and five fatty acids, was pyrogenic and an IL-1 inducer (EP+/LAF+); but crude B.
pertussis
lipid A (0.25 N HCl), which lacked the glycosidic phosphoryl group, was 1,000-fold less pyrogenic than the diphosphorylated lipid A, yet it retained its IL-1-inducing capacity (EP-/LAF+). Purified N. meningitidis lipid A was not an inducer of IL-1 release and purified B.
pertussis
lipid A exhibited identical pyrogenicity as the parent LPS but was devoid of any IL-1-release inducing capacity (EP+/LAF-). These results demonstrate that for some endotoxins, purified lipid A is unable to induce IL-1 release by human monocytes; however, it is pyrogenic, supporting the hypothesis that IL-1 and EP are induced by different determinants on the LPS molecule.
...
PMID:Inability of pyrogenic, purified Bordetella pertussis lipid A to induce interleukin-1 release by human monocytes. 287 60
A new gel filtration method was developed for purification of R-type lipopolysaccharides (lipooligosaccharides) from some nonenteric gram-negative bacteria, including Neisseria meningitidis, Haemophilus influenzae, and Bordetella
pertussis
. These wild-type lipooligosaccharides are poorly extractable by the phenol-chloroform-ether extraction method of C. Galanos, O. Luderitz, and O. Westphal [1969) Eur. J. Biochem. 9, 245-249) and therefore a new procedure was developed for their isolation. The lipooligosaccharides (LOS) were first extracted by hot phenol-
water
, treated with RNase, then disaggregated in deoxycholic acid, and purified by gel filtration on Sephadex G-75. By comparison the conventional hot phenol-
water
purification method using repeated ultracentrifugations yielded less LOS. The yield of LOS by gel filtration was 30 to 108% higher and the purity was better.
...
PMID:A method for purification of bacterial R-type lipopolysaccharides (lipooligosaccharides). 288 9
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