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- Bergenfelz, A, et al.
(författare)
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Pancreastatin plasma levels in patients with primary hyperparathyroidism
- 2000
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Ingår i: World Journal of Surgery. - : Springer Science and Business Media LLC. - 0364-2313 .- 1432-2323. ; 24:12, s. 83-1579
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Tidskriftsartikel (refereegranskat)abstract
- Pancreastatin, a C-terminally amidated peptide derived from chromogranin A, is known to inhibit insulin secretion, pancreatic enzyme release, and gastric acid secretion. It also inhibits parathyroid hormone (PTH) secretion in animals. The physiologic and clinical relevance of pancreastatin in humans, however, is not known. Because pancreastatin has been found in parathyroid adenomas, we investigated the plasma levels in patients with primary hyperparathyroidism (pHPT). Thirteen patients operated on for solitary parathyroid adenoma were investigated. Plasma levels of pancreastatin and serum levels of ionized calcium and intact PTH were measured before and 6 weeks after operation. In 10 patients the levels were also monitored before and 60 minutes after adenoma excision. The adenomas were investigated for pancreastatin immunoreactivity by immunocytochemistry. The median weight of the excised parathyroid adenoma was 0.64 g (range 0.07-2.00 g). Cells displaying pancreastatin immunoreactivity were present in all adenomas examined and varied in number and immunostaining intensity among and within the adenomas. Intraoperatively, after adenoma excision the levels of PTH and pancreastatin declined (p < 0.01), whereas the levels of ionized calcium did not change (p = 0.96). At the 6-week follow-up the levels of ionized calcium and PTH had decreased compared to the preoperative levels (p < 0.01), and all patients were normocalcemic. In contrast, the pancreastatin levels were not changed (14.5 +/- 6.1 pmol/L preoperatively vs. 12.8 +/- 11.2 pmol/L 6 weeks postoperatively; p = 0.12). In patients with pHPT, pancreastatin is likely to be produced by the parathyroid adenoma. The changes in pancreastatin levels immediately after surgery warrant further investigation.
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| 2. |
- Schmidt, D, et al.
(författare)
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The effect of the vasoactive intestinal polypeptide agonist Ro 25-1553 on induced tone in isolated human airways and pulmonary artery
- 2001
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Ingår i: Naunyn-Schmiedeberg's Archives of Pharmacology. - : Springer Science and Business Media LLC. - 0028-1298 .- 1432-1912. ; 364:4, s. 314-320
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Tidskriftsartikel (refereegranskat)abstract
- Ro 25-1553 is a metabolically stable analogue of endogenous vasoactive intestinal polypeptide (VIP). This compound is a potent bronchodilator in vitro as well as in vivo. Moreover, Ro 25-1553 has been shown to be highly selective of the VPAC2 receptor. We assessed the effect of Ro 25-1553 on isolated human bronchi and pulmonary arteries in vitro. Macroscopically normal human airways and pulmonary arteries were obtained from patients undergoing surgery for lung cancer. The relaxing capability of Ro 25-1553 on bronchial and pulmonary artery tone was measured using standard techniques. Bronchial rings were pre-contracted with 0.1 mM histamine, and tone in pulmonary artery rings was induced with 10 microM PGF2alpha. Increasing concentrations of Ro 25-1553 within a range of 1 pM to 10 microM were added and isometric tension changes were recorded. Ro 25-1553 caused a concentration-dependent relaxation of airway and pulmonary artery preparations, with an EC50 of approximately 10 nM and a maximal relaxation of 70%-75% of the induced tone. The presence of VPAC2 receptors in the two tissues, though low in density, was confirmed by in situ hybridization, immunocytochemistry and ligand binding. These findings indicate that the VIP analogue Ro 25-1553 may be useful in the treatment of asthma and/or chronic obstructive pulmonary diseases.
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