| 1. |
- Adner, Mikael, et al.
(författare)
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Human endothelin ETA receptor antisense oligodeoxynucleotides inhibit endothelin-1 evoked vasoconstriction
- 1994
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Ingår i: European Journal of Pharmacology. - 1879-0712. ; 261:3, s. 281-284
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Tidskriftsartikel (refereegranskat)abstract
- Antisense oligodeoxynucleotides to endothelin ETA receptor mRNA were used to characterize vascular smooth muscle receptors. The concentration-response curve showed a significant attenuation of endothelin-1-induced contraction in circular segments of the human superficial temporal artery. Endothelin ETB receptor antisense or mismatch oligodeoxynucleotides showed no alteration of the endothelin-1-induced contraction. Complementary experiments with the selective endothelin ETA receptor antagonist FR139317 demonstrated a shift of the concentration-response curve to the right in a competitive manner (pA2 = 6.93). The specific method of using the receptor antisense oligodeoxynucleotides approach revealed the presence of endothelin ETA receptors mediating contraction in the human superficial temporal artery.
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| 2. |
- Bergdahl, Anders, et al.
(författare)
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Neuropeptide Y potentiates noradrenaline-induced contraction through the neuropeptide Y Y1 receptor
- 1996
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Ingår i: European Journal of Pharmacology. - 1879-0712. ; 316:1, s. 59-64
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Tidskriftsartikel (refereegranskat)abstract
- To elucidate which neuropeptide Y receptor subtype is responsible for the neuropeptide Y-induced potentiation of the noradrenaline-evoked contraction in human omental arteries we used antisense oligodeoxynucleotide (Antisense), the new selective neuropeptide Y Y1 receptor antagonist, BIBP3226 {(R)-N2-(diphenylacetyl)-N-[(4-hydroxyphenyl) methyl]-D-arginine-amide} and the reverse transcriptase-polymerase chain reaction (RT-PCR). Neuropeptide Y significantly potentiated the noradrenaline-induced contraction in non-incubated vessels (pEC50 6.4 +/- 0.2 vs. 5.9 +/- 0.2) and in vessels incubated with 1 microM Sense oligodeoxynucleotide (Sense) (pEC50 6.0 +/- 0.1 vs. 5.6 +/- 0.2). In vessels incubated with 1 microM Antisense the potentiating effect of neuropeptide Y was completely abolished. BIBP3226 (1 microM) inhibited the neuropeptide Y-induced potentiation in human omental arteries (pEC50 5.8 +/- 0.3 vs. 6.4 +/- 0.2). Finally, messenger RNA for the neuropeptide Y Y1 receptor was detected using RT-PCR. On the basis of our results we conclude that the neuropeptide Y-induced potentiation of the noradrenaline-induced contraction is mediated by the neuropeptide Y Y1 receptor.
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| 3. |
- Edvinsson, Lars, et al.
(författare)
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Neuropeptide Y in sympathetic co-transmission: recent advances in the search for neuropeptide Y antagonists
- 1994
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Ingår i: Pharmacology and Toxicology. - 1600-0773. ; 74:4-5, s. 193-201
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Tidskriftsartikel (refereegranskat)abstract
- Since the discovery of neuropeptide Y which is co-stored and co-operate with noradrenaline (NA) in sympathetic nerve fibers, several scientific groups have searched for structures with neuropeptide Y antagonistic properties. Research has mainly focused on various peptide fragments which originate from or are related to the neuropeptide Y sequence. Some non-peptide antagonists have been proposed but they are mostly of low potency and non-selective. Our recent observations that alpha-trinositol (D-myo-inositol 1.2.6-trisphosphate) is an inhibitor of neuropeptide Y effects will hopefully lead to the development of useful non-peptide neuropeptide Y inhibitors. As a novel approach the highly selective approach of down-regulating neuropeptide Y receptors with antisense oligodeoxynucleotides is also discussed. Neuropeptide Y antagonistic agents would help us to understand the physiological role of neuropeptide Y and may serve as useful medication in circulation disorders.
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| 4. |
- Edvinsson, Lars, et al.
(författare)
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Sensory nerve terminal activity in severe hypertension as reflected by circulating calcitonin gene-related peptide (CGRP) and substance P
- 1992
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Ingår i: Blood Pressure. - : Informa UK Limited. - 0803-7051 .- 1651-1999. ; 1:4, s. 223-229
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Tidskriftsartikel (refereegranskat)abstract
- In patients with severe hypertension and in age and sex matched controls the circulating levels of calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) and substance P-LI were measured. Samples were taken before medication, after 2-4 weeks and 2-12 months of pharmacological treatment to normotension. In the control group CGRP-LI levels were significantly higher for females than for males. No such relation was seen for substance P-LI. There were no correlations between CGRP-LI, substance P-LI or blood pressure. In the untreated acute hypertensive group there was a significant correlation between circulating levels of CGRP-LI and both diastolic and systolic blood pressure. No such relationship was seen for substance P-LI. The plasma levels of substance P-LI were significantly elevated (2.8 +/- 4.0) compared to controls (1.3 +/- 1.3, pmol/l, mean +/- S.D., p < 0.01). The levels of CGRP-LI did not differ from the control group. After 2-4 weeks of treatment the blood pressure decreased significantly and the plasma levels of substance P-LI were normalized while the CGRP-LI still did not differ from that of controls. After 2-12 months of treatment the blood pressure was still normalized, and the plasma levels of CGRP-LI and substance P-LI were not different from the control group. In the present study there was a positive correlation in hypertensives between the circulating CGRP-LI levels and diastolic and systolic blood pressure and elevated levels of substance P-LI. This would implicate the existence of a dynamic control through which the sensory system may register and damp the pressure response.
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| 5. |
- Erlinge, David, et al.
(författare)
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Characterisation of an ATP receptor mediating mitogenesis in vascular smooth muscle cells
- 1995
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Ingår i: European Journal of Pharmacology. - : Elsevier BV. - 1879-0712 .- 0922-4106. ; 289:1, s. 135-149
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Tidskriftsartikel (refereegranskat)abstract
- Adenosine triphosphate (ATP), a co-transmitter in sympathetic nerves and released from platelets, has recently been shown to stimulate growth of vascular smooth muscle cells. It might therefore contribute to the development of vascular hypertrophy seen in hypertension and atherosclerosis. We aimed at characterising the receptor mediating this mitogenic effect in rat aorta smooth muscle cells. The potency of agonists indicates a P2 purinoceptor since ATP > or = ADP >> AMP, adenosine. The P2x-receptor subtype, which is responsible for ATP induced vasoconstriction in rat aorta, does not mediate the mitogenic effect since alpha, beta-methyleneATP had no effect and beta, gamma-methyleneATP had lower potency than ATP. The P2Y-receptor subtype was excluded since the selective agonist 2-methylthioATP had weak effect with lower potency than ATP. When we studied the involvement of other nucleotides similar effects were seen of the purines ATP, GTP and ITP; also the pyrimidine UTP had powerful mitogenic effects (Emax = 52% of ATP) with similar potency. Nucleotides with fewer phosphate groups showed a stepwise fall in mitogenic effect. This indicates involvement of a nucleotide-receptor (P2U). Ap4A were of equal potency and effect as ATP. There was strong correlation between the mitogenic effects of the nucleotides and analogues with both 45Ca(2+)-influx and inositol phosphate (IP) production, indicating that they may participate in mediating the mitogenic response. This is the first study describing the potencies for the mitogenic effects of the selective ATP-analogues and other nucleotides in vascular smooth muscle cells. The receptor characterisation indicates a nucleotide-receptor similar to the receptor which stimulates 45Ca(2+)-influx and inositol phosphate-formation in rat aorta smooth muscle cells. Substances related to ATP such as GTP, ITP, UTP and Ap4A which also can be released extracellularly in vivo stimulate mitogenesis of rat aorta smooth muscle cells through the same receptor.
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| 6. |
- Erlinge, David, et al.
(författare)
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Human neuropeptide Y Y1 receptor antisense oligodeoxynucleotide specifically inhibits neuropeptide Y-evoked vasoconstriction
- 1993
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Ingår i: European Journal of Pharmacology. - 1879-0712. ; 240:1, s. 77-80
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes a new approach for the development of an inhibitor of the contractile responses of neuropeptide Y in human blood vessels by the use of an antisense oligodeoxynucleotide complementary to human neuropeptide Y Y1 receptor mRNA. One micromolar of an antisense 18-base oligodeoxynucleotide (hY1-AS), corresponding to the human Y1 receptor NH2-terminus, was incubated with segments of human subcutaneous arteries and veins for 48 h at 37 degrees C. Control vessels were incubated with the corresponding sense oligodeoxynucleotide (hY1-S) or a 3-base mismatched antisense oligodeoxynucleotide (hY1-MM) or no oligodeoxynucleotide. The contractile response to neuropeptide Y was markedly attenuated in both arteries and veins after treatment with hY1-AS, but was unaffected by hY1-S or hY1-MM. The pD2 values, i.e. the potency of neuropeptide Y, did not differ in hY1-AS treated vessels, suggesting a non-competitive receptor interaction as a result of down-regulation of Y1 receptors. Responses to noradrenaline or high K+ were unaffected by hY1-AS. This study may represent a new and highly specific approach to vascular pharmacology.
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| 7. |
- Erlinge, David, et al.
(författare)
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Mitogenic effects of ATP on vascular smooth muscle cells vs. other growth factors and sympathetic cotransmitters
- 1993
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Ingår i: American Journal of Physiology - Heart and Circulatory Physiology. - 1522-1539. ; 265:4, s. 1089-1097
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Tidskriftsartikel (refereegranskat)abstract
- The sympathetic nervous system has been shown to exert a trophic influence on vascular smooth muscle cells (VSMC). Therefore, we studied the growth-regulating effects of the sympathetic cotransmitters ATP, neuropeptide Y (NPY), and norepinephrine (NE). ATP in concentrations of 1-100 microM greatly increased the incorporation of [3H]thymidine in VSMC from rat aorta and vena cava. ATP also increased cell number and total protein content. The maximal effect on [3H]thymidine incorporation was greater than for epidermal growth factor (20 ng/ml) or insulin (1 microgram/ml) and approximately one-half that of 10% fetal calf serum. The potency series of other nucleotides and analogues of ATP was ATP > beta, gamma-methyleneATP (AMP-PCP) > ADP > adenosine > alpha, beta- methyleneATP (AMP-CPP) > 2-methylthioATP, indicating involvement of a P2 receptor, however, it does not meet proposed pharmacological criteria of either the P2x or P2y subclass. Several proposed P2 receptor antagonists were without effect. The effect of ATP could be mediated by a "nucleotide receptor," since UTP also stimulated [3H]thymidine incorporation. In our model, there was a strong correlation between the mitogenic effects of ATP, AMP-CPP, AMP-PCP, and UTP and their ability to stimulate influx of extracellular Ca2+ (Ca2+o). Moreover, the mitogenic effect of ATP was increased by high concentrations of Ca2+o. Taken together with data showing the lack of involvement of several other second-messenger systems, this indicates a critical role for Ca2+o in mediating the mitogenic effects of ATP. Amiloride, known to inhibit the action of several growth factors, also inhibited ATP-induced mitogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)
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| 8. |
- Erlinge, David, et al.
(författare)
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Neuropeptide Y-like immunoreactivity and hypertension
- 1992
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Ingår i: Journal of Hypertension. - 1473-5598. ; 10:10, s. 1221-1225
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Neuropeptide Y is a co-transmitter with noradrenaline in sympathetic neurons supplying arteries and veins with potent contractile effects. To investigate the role of neuropeptide Y in hypertension, we measured the circulating levels of neuropeptide Y and noradrenaline in patients with severe hypertension. DESIGN: Samples were collected from patients with untreated, severe hypertension (diastolic blood pressure > 120 mmHg) and in age- and sex-matched controls. After treatment with beta-adrenoceptor blockers, diuretics, angiotensin converting enzyme inhibitors of calcium antagonists, samples were taken from the patients during 12 months. METHODS: The circulating levels of neuropeptide Y-like immunoreactivity (NPY-LI) were measured with a radioimmunoassay using a rabbit antiserum. Catecholamines were measured using high-performance liquid chromatography and electrochemical detection. RESULTS: There was a significantly higher level of NPY-LI in the patients when they were compared with the controls. However, there was no correlation either in the controls or in the hypertensives between systolic blood pressure, diastolic blood pressure and NPY-LI or noradrenaline. The increased level of NPY-LI in plasma remained elevated for up to 12 months despite reduction in blood pressure to acceptable levels. The noradrenaline level was not increased before treatment, after 2-4 weeks or after 2-12 months treatment. CONCLUSION: The high level of NPY-LI may represent a marker for higher activity of the sympathetic nervous system which is not controlled by the treatment of blood pressure to normotension.
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| 9. |
- Erlinge, David, et al.
(författare)
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Neuropeptide Y stimulates proliferation of human vascular smooth muscle cells: cooperation with noradrenaline and ATP
- 1994
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Ingår i: Regulatory Peptides. - 1873-1686. ; 50:3, s. 259-265
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Tidskriftsartikel (refereegranskat)abstract
- Since the sympathetic nervous system has been shown to exert a trophic influence on vascular smooth muscle cells (SMC), we studied the growth regulating effects of neuropeptide Y (NPY) in cooperation with the sympathetic co-transmitters noradrenaline and adenosine triphosphate (ATP) in human vascular SMC. NPY stimulated DNA synthesis in human SMC grown from subcutaneous arteries and veins (diameter: 0.4 mm) measured by [3H]thymidine incorporation. Also cell number and protein synthesis were stimulated. The effect was mediated through the Y1-receptor and not Y2 or Y3 since the Y1-selective NPY analogue Pro34-NPY and peptide YY stimulated mitogenesis in the same magnitude as NPY while the NPY-fragment NPY13-36 only had minor effects. The effect was blocked by pretreating the cells with pertussis toxin indicating a Gi/o-coupled effect. The other sympathetic co-transmitters, noradrenaline and ATP, also stimulated mitogenesis in the human SMC in a similar magnitude as NPY. When added together NPY and noradrenaline potentiated each other in the mitogenic response. ATP had mainly additive effects. This is the first demonstration that NPY, noradrenaline and ATP stimulates growth in human vascular SMC. This suggests a role of the sympathetic cotransmitters in modulating vascular tone, but also by inducing hypertrophy/hyperplasia with possible clinical consequences.
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| 10. |
- Erlinge, David, et al.
(författare)
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Tyrphostin inhibition of ATP-stimulated DNA synthesis, cell proliferation and fos-protein expression in vascular smooth muscle cells
- 1996
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Ingår i: British Journal of Pharmacology. - 1476-5381. ; 118:4, s. 1028-1034
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Tidskriftsartikel (refereegranskat)abstract
- 1. We and others have shown that extracellular ATP (adenosine triphosphate), released from sympathetic nerves and platelets, stimulates growth of vascular smooth muscle cells (SMC). To study the importance of tyrosine kinases for ATP-mediated proliferation in vascular smooth muscle cells we used tyrphostins, a recently developed group of highly specific inhibitors of tyrosine kinases. 2. ATP induced a powerful concentration-dependent increase in DNA synthesis measured by [3H]-thymidine incorporation in rat aorta SMC (RASMC) and an increase in total cell number after 72 h of incubation as measured by an enzymatic cell proliferation assay. Tyrphostin 25 (10(-5) M) had no effect per se on basal DNA synthesis but reduced ATP-stimulated DNA synthesis and increase in cell number in a dose-dependent manner. Higher concentrations of ATP could not reverse the inhibitory effect of tyrphostin 25. The potency of several (six) other tyrphostins was also examined and found to be slightly greater than tyrphostin 25 with equal efficacy. 3. When RASMC were incubated with 10(-5) M ATP for 2 h, nearly all of the cells (87 +/- 5%) were intensely stained with an antibody to the Fos protein while in the controls only 1 +/- 2% of the cells were weakly stained. Tyrphostin 25 greatly reduced the Fos-protein staining (14 +/- 2%). 4. ATP induced a concentration-dependent increase in 45Ca(2+)-influx and formation of inositol phosphates (IPtotal) in RASMC. These effects were not inhibited by tyrphostin 25. 5. Tyrphostin 25 did not alter ATP-induced contraction in ring segments of rat aorta. 6. In conclusion, tyrphostin 25 inhibited ATP-induced DNA synthesis, cell proliferation and Fos-protein expression, but not ATP-induced 45Ca(2+)-influx, inositolphosphate-production or vasoconstriction. This indicates that the mitogenic effect of ATP on vascular smooth muscle cells is dependent on tyrosine kinases in contrast to the contractile effect of ATP in blood vessels.
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