Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Graft-versus-host reactions were induced in adult F1 hybrid animals by injecting parental spleen cells. Adenylate cyclase activity was determined in the washed cell particles of the lymphoid tissues. During a time course study of the regional GVH reaction an increase in lymph node weight was apparent at day 2, whereas the adenylate cyclase activity increased at day 4 after the injection. Maximal lymph node hypertrophy and adenylate cyclase activation were observed 8 to 10 days after initiation of the GVH response. Adenylate cyclase stimulation by epinephrine of the GVH response. Adenylate cyclase stimulation by epinephrine and glucagon in experimental preparations was less than in the control. NaF was stimulatory only in the control preparations. Ca-2+ in concentrations up to 8 mM had no inhibitory effects on the control or experimental preparations. The pattern of responses of the experimental preparations to Zn-2+ and Cu-2+ was different than the control; however, in high concentrations both of these cations had marked inhibitory effects. An increase in the adenylate cyclase activity was also direct relationship between the adenylate cyclase activity and the cytolytic activity of spleen cells from mice undergoing systemic GVH reaction. These results can be explained on the basis of alterations in the cell membranes, and it is suggested that such changes play an important role in the pathogenesis of GVH disease.
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PMID:Adenylate cyclase activation in lymphoid tissues during graft-versus-host reaction. 23 44

The activity of phosphate-dependent glutaminase and glutamine metabolism by tissues known markedly to utilize or synthesize glutamine (or both) were studied in rats made septic by cecal ligation and puncture technique and compared with the same measures in rats that underwent sham operation (laparotomy). Blood glucose level was not markedly different in septic rats, but lactate, pyruvate, alanine, and glutamine levels were markedly increased. Conversely, blood ketone body concentrations were significantly decreased in septic rats. Both plasma insulin and glucagon levels were markedly elevated in response to sepsis. The maximal activity of phosphate-dependent glutaminase was decreased in the small intestine, increased in the kidney and mesenteric lymph nodes, and unchanged in the liver of septic rats. Arteriovenous concentration difference measurements across the gut showed a decrease in the net glutamine removed from the circulation in septic rats. Arteriovenous concentration difference measurements for glutamine showed that both renal uptake and skeletal muscle release of the amino acid were increased in response to sepsis, whereas measurements across the hepatic bed showed a net uptake of glutamine in septic rats. Enterocytes isolated from septic rats exhibited a decreased rate of utilization of glutamine and production of glutamate, alanine, and ammonia, whereas lymphocytes isolated from septic rats showed an enhanced rate of utilization of glutamine and production of glutamate, aspartate, and ammonia. It is concluded that, during sepsis, glutamine uptake and metabolism are enhanced in renal and lymphoid tissue but decreased in that of the small intestine, with increased rates of release by skeletal muscle; however, the liver appears to utilize glutamine in septic rats.
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PMID:Maximal activity of phosphate-dependent glutaminase and glutamine metabolism in septic rats. 206 39

Prolonged survival of human islet xenografts under the kidney capsule of diabetic rats was achieved. Human islet xenograft survival time for the nonimmunosuppressed and single-dose antithymocyte serum-treated rats were 3.7 +/- 0.33 days (mean +/- SE, n = 6) and 4.2 +/- 0.63 (n = 4), respectively. In the recipients given 5 doses of ATS after islet transplantation, the graft survival time was significantly prolonged to 18.2 +/- 1.9 days (n = 6). An intravenous glucose tolerance test was performed on 3 recipients with a functional graft 12 days after xenotransplantation. The mean K rate was 1.44 +/- 0.43 (n = 3) compared with that of 2.1 +/- 0.14 (n = 5) found in normal control rats. Human C-peptide was present in the rat recipients following islet transplantation. In addition all 3 recipients showed significant basal human C-peptide values posttransplant and achieved levels of above 2.4 ng/ml during IVGTT. Morphologic and immunohistochemical examination of the islet grafts show that in recipients without immunosuppression or with a single dose of ATS, there was marked degree of fibrosis with little endocrine tissue left in the graft area by day 5. In contrast, the xenograft from recipients treated with 5 doses of ATS still contained well-preserved islet tissue with many insulin and glucagon containing cells on the day of graft removal when blood glucose had returned to the hyperglycemic level. Infiltration of the graft area with lymphoid cells (OX1+, OX8+, and W3/25+) was prominent, but they were not detected within the islets. Staining with monoclonal antibody clone L243 did not detect any expression of human class II antigen on the human pancreatic endocrine cells undergoing rejection by the host. This study has shown that with adequate immunosuppression human islet xenograft can normalize the blood glucose with prolonged survival time in diabetic rat recipients. The discordant xenotransplantation model used in this study would be useful for future xenotransplantation studies.
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PMID:Human islet xenograft survival in diabetic rats. A functional and immunohistochemical study. 210 14

The ability of members of the secretin-glucagon family of peptides to modulate the responses of mouse lymphoid cells stimulated with Concanavalin A (Con A), Lipopolysaccharide (LPS) and alloantigens was determined. It was observed that vasoactive intestinal peptide (VIP) and peptide having NH2-terminal histidine and COOH-terminal Isoleucine (PHI) inhibited the incorporation of 3H-methyl-thymidine by cells stimulated with Con A (55% inhibition) or alloantigen-bearing cells (40% inhibition). Secretin was approximately 10,000 less effective as an immunomodulator. Other members of the neuropeptide family, including glucagon and gastric inhibitory peptide, were ineffective in affecting mitogenesis elicited by Con A (20% inhibition). Lipopolysaccharide stimulated spleen cells were refractory to modulation by all members of the secretin-glucagon family of peptides (less than 5% modulation). The inhibition measured was concentration dependent over the range of 10(-6) to 10(-16) M. A peptide fragment of VIP encompassing amino acid residues 10-28, although capable of modulating in vitro responses, was 30-50% less effective than intact VIP. In addition, a VIP specific binding assay for mouse lymphoid cells was described. The binding of 125I-VIP to lymph node cells was rapid, saturable and reversible. Apparent equilibrium was reached within 15 minutes and nonspecific binding, measured as 125I-VIP binding in the presence of an excess (2 x 10(-7) M) of native VIP, did not exceed 25% of the total binding. In competitive experiments using VIP related peptides, PHI but not gastric inhibitory peptide, glucagon or secretin was able to significantly inhibit 125I-VIP binding. PHI had only one-eighth of the competitive capacity of native VIP. Scatchard analyses indicated the existence of a single class of high affinity receptors on lymph node cells (KD = 3.46 nM; 26,000 sites/cell). 125I-VIP specific binding to purified T cells (14%) was markedly higher than to B cells (3% binding). Thymocytes bound less than 2% of the label and had relatively few VIP binding sites (8,000) as compared with purified T cells (45,000 sites/cell). There was variability in the ability of various T cells tumors and functional T cell clones to bind 125I-VIP. The role of VIP as a physiological modulator of T cell activation is discussed.
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PMID:Analysis of the immunomodulatory properties of the secretin-glucagon family of peptides on mouse lymphoid cell functions and the demonstration of specific receptors on T cells. 283 22

Receptors for vasoactive intestinal peptide (VIP) have been characterized in rat lymphoid cells. The interaction of [125I] VIP with blood mononuclear cells was rapid, reversible, specific and saturable. At apparent equilibrium, the binding of [125I] VIP was competitively inhibited by native VIP in the 0.01-100 nM range concentration. The binding data were compatible with the existence of two classes of receptors: a high-affinity class with a Kd = 0.050 +/- 0.009 nM and a low binding capacity (2.60 +/- 0.28 fmol/10(6) cells), and a low-affinity class with a Kd = 142 +/- 80 nM and a high binding capacity (1966 +/- 330 fmol/10(6) cells). Secretin, glucagon, insulin and somatostatin did not show any effect at a concentration as high as 100 nM. With spleen lymphoid cells, stoichiometric studies were performed. The binding data were compatible with the existence of two classes of receptors: a high-affinity class with a Kd = 0.100 +/- 0.033 nM and a low binding capacity (4.60 +/- 1.07 fmol/10(6) cells), and low-affinity class with a Kd = 255 +/- 110 nM and high binding capacity (2915 +/- 1160 fmol/10(6) cells). With thymocytes, no binding was obtained under different conditions.
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PMID:Interaction of vasoactive intestinal peptide (VIP) with rat lymphoid cells. 301 77

Islet cell function was studied in pancreatectomized primates with functioning segmental pancreatic allografts more than 100 days after transplantation. Segmental allograft recipients were immunosuppressed with total lymphoid irradiation (TL1) and cyclosporine (CSA). After 100 days, islet function was assessed, at which stage immunosuppression was terminated. Glucose, insulin, glucagon, and C-peptide response was assessed during intravenous glucose tolerance test (IVGTT) and during arginine and tolbutamide stimulation. In eight normoglycaemic primates in which immunosuppressive treatment had been stopped and with mean graft survival of 145 days, islet stimulation was associated with moderate glucose intolerance, reduced K-values, hypoinsulinaemia, and low C-peptide values. Postmortem findings in all animals intentionally killed revealed severe graft atrophy in the absence of significant rejection. Severe graft atrophy in normoglycaemic primates, together with significantly impaired graft function after segmental pancreatic transplantation compared to normal animals, suggest that transplantation of the whole pancreas may be mandatory if normal or near-normal function is to be achieved.
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PMID:Islet cell function in long-term surviving primates after segmental pancreatic allotransplantation. 328 7

Bovine glucagon, a polypeptide of 29 amino acids, was immunogenic in guinea pigs. The immunologic determinants of glucagon were investigated using isolated tryptic peptides of the hormone. Antibodies from virtually all of more than two dozen animals had specificity primarily for the amino-terminal heptadecapeptide (NM) and showed little or no binding with the carboxy-terminal undeca- and dodecapeptides (C). The smallest synthetic peptide of a series initiated at residue 16 which measurably bound antibody comprised residues 5-16 of glucagon. In cellular immune assays, both NM and C elicited delayed cutaneous reactions and inhibited the migration of peritoneal cells from immune animals. However, only intact glucagon and its C fragment stimulated lymphoid cells to synthesize DNA. While glucagon was somewhat more active than C, the addition of NM to C did not enhance its transforming activity. The smallest synthetic carboxy-terminal peptide with discernible transforming activity comprised residues 19-29 of glucagon. In both native and synthetic C peptide preparations, the undecapeptide was generally more active than the dodecapeptide, although cells from different animals gave different response patterns. The difference between the two is the presence of arginine at the amino-terminus of the peptide chain. Thus, the recognition specificity of populations of antigen-reactive cells from different animals displays a variation which is at least superficially analogous to that of populations of antibody molecules. In limited experiments using NM and C peptides as immunogens, neither gave rise to delayed hypersensitivity or to glucagon-binding circulating antibody, following a regimen which invariably provoked these responses when glucagon itself served as the immunogen. These results indicate that glucagon was cleaved by trypsin along functional lines into two parts, one of which housed the major antigenic determinant and the other of which carried the major immunogenic determinant, and they are highly compatible with a two-cell mechanism of immune induction. An apparent dissociation between the capacity to provoke delayed hypersensitivity reactions and to transform antigen-reactive cells in culture was observed.
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PMID:The functional dissection of an antigen molecule: specificity of humoral and cellular immune responses to glucagon. 410 86

Adenylate cyclase of homogenates or lysates of mouse and rat lymphoid tissues was activated by the addition of fluoride ion, epinephrine, or norepinephrine, but not by any of several other hormones. The catecholamine stimulation was characterized as beta-adrenergic. This activity was localized in the small lymphoid cells, was greater in thymic than in splenic or mesenteric node cells, and also was greater in mouse than in rat cells. Catecholamine-stimulated activity of mouse thymocytes remained constant from the 17-19th day of fetal development to 5 weeks after birth; it subsequently decreased to about one-half of the activity by 7-8 weeks. Similar decreases with age occurred in mouse spleen and rat thymus. In contrast, the glucagon-stimulated activity of rat liver increased during a similar period. Hypophysectomy of rats at 3 weeks did not influence the amount of cyclase activity of thymocytes assayed at 7 weeks. When intact mouse thymocytes were first incubated in a culture medium at 37 degrees C with epinephrine or norepinephrine, a second addition of catecholamine after cell lysis no longer stimulated the enzymes. This loss of stimulation was selective, since basal activity and stimulation by fluoride ion were not affected. Incubation of intact cells with phytohemagglutinin markedly decreased the activity of lysates, whether assayed in the presence or absence of catecholamine or fluoride. In contrast, phytohemagglutinin added directly to the assay had no effect. No alternations occurred in adenylate cyclase activity as a result of the incubation of a 1:1 mixture of thymocytes from two strains of mice selected for the capacity of the cells to produce a mixed lymphocyte response.
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PMID:Properties of adenylate cyclase of lymphoid cells. 528 May 25

The objective of the present studies was to determine whether the existence of functional glucagon receptors could be established on lympoid cells. The glucagon receptor, which positively regulates adenylate cyclase, is a member of the superfamily of seven transmembrane domain G-protein coupled receptors. Previously reported specific binding with [125I]-glucagon to a variety of lymphoid and myeloid cell preparations suggests that glucagon receptors are expressed within the immune system. In the present study, Northern analysis of polyA RNA isolated from primary mouse and rat derived lymphoid tissues and lymphoid cell lines EL-4.IL-2, Jurkat E6-1, CH12LX, and BCL1-3B3 cells were probed with a 32P-labeled human hepatic glucagon receptor. Mouse spleen and thymus, rat spleen, and the B cell line, CH12LX, all possessed a single 1.5 kb fragment (BCL1-3B3, 1.4 kb) which hybridized to the glucagon receptor cDNA probe, as compared to mouse liver which exhibited a 2.8 kb fragment. EL-4.IL-2 and Jurkat E6-1 cells possessed a 3.7 kb fragment with an additional 2.75 kb band present in Jurkat E6-1 cells. Treatment of mouse splenocytes and T- and B-lymphoma cells with glucagon (0 - 100 nM) produced a dose-dependent enhancement in intracellular cAMP which was maximal at 5 min post treatment followed by a gradual decline. Direct addition of glucagon to spleen cell cultures over a broad concentration range produced no effect on either lymphoproliferation following stimulation with anti-CD3 mAb, or LPS nor on the antibody forming cell (AFC) response to sRBC. Conversely, glucagon effectively reversed the suppression of the sRBC AFC response produced by delta9-tetrahydocannabinol (delta9-THC), and partially reversed the suppression produced by 2',3'-dideoxyadenosine, both of which are potent inhibitors of adenylate cyclase. These studies confirm the expression of functional glucagon receptors on lymphoid cells.
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PMID:Expression of functional glucagon receptors on lymphoid cells. 863 21

The number and the size of the Langerhans islets in the pancreata of most of investigated cases with diabetic foetopathy is increased (polynesia and macronesia). The B endocrine cells are immunoreactive for both insulin and IAPP, the reaction for IAPP being weaker in comparison with the controls. In one of the cases (the mother with long history of treated type 1 diabetes, who died during delivery) no presence of insulin-immunoreactive of PAF positive B cells is discovered. The reactivity for glucagon and somatostatin in the pancreata with diabetic foetopathy is found to be similar to the controls. In the vicinity of some islets lymphoid cell infiltrations are observed.
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PMID:[Immunohistochemical studies of the pancreas in newborns with diabetic fetopathy]. 896 31


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