0000000000268546
AUTHOR
Holger Klapproth
showing 6 related works from this author
Acetylcholine and nicotine stimulate the release of granulocyte-macrophage colony stimulating factor from cultured human bronchial epithelial cells.
1998
Primary cultures of human bronchial epithelial cells (HBE-cells) were established to measure granulocyte-macrophage colony stimulating factor (GM-CSF) release. HBE-cells showed a basal GM-CSF release (82+/-20 ng/well/24 h; 30 donors), which was increased by interleukin-1 beta(IL-1beta, 1 ng/ml) by 270%. This effect was blocked by 1 microM dactinomycin or 10 microM cycloheximide, i.e. the stimulatory effect of IL-1beta depended on de-novo synthesis. Histamine (100 microM) and acetylcholine ( 100 nM) stimulated GM-CSF release more than two-fold above the baseline. Nicotine (1 microM) increased GM-CSF release to a similar extent, and this effect was prevented by 30 microM (+)-tubocurarine. The…
Release of [3H]Acetylcholine in Human Isolated Bronchi: Effect of Indomethacin on Muscarinic Autoinhibition
1995
Receptor-mediated regulation of acetylcholine release in the airways, particularly in humans, remains unclear. In the present study, the tissue content of acetylcholine and release of [3H]acetylcholine were measured in freshly dissected human bronchi obtained at thoracotomy. Large (main and lobar bronchi) and small (segmental and subsegmental bronchi) airways contained considerable amounts of endogenous acetylcholine (300 +/- 50 pmol/100 mg wet weight), whereas significantly less was found in lung parenchyma (60 +/- 30 pmol/100 mg). Isolated small bronchi incubated in an organ bath with the precursor [3H]choline synthesized significant amounts of [3H]acetylcholine (26,000 +/- 4,000 dpm/100 …
Variability of isozyme pattern, chromosome number, and latex colour and components in the closely related Papaver duhium L. and P. lecoqii Lamotte in…
1995
Summary The variability of nine different isozyme systems, chromosome number, colour of fresh and dried latex and presence or absence of meconic acid was investigated in altogether 45 populations of Papaver dubium and P. lecoqii mainly from C Europe. It was found that P. dubium is hexaploid with 2n = 42 chromosomes, has brown dried latex, and contains meconic acid. P. lecoqii is tetraploid with 2n = 28 chromosomes, has red dried latex, and lacks meconic acid. The two taxa can also be distinguished by differences in three of the nine isozymes analysed, and are almost completely monomorphic for their respective isozyme pattern. It is concluded that the two taxa, which cannot be reliably disti…
Mammalian glial cells in culture synthesize acetylcholine.
1997
In the present study we demonstrate that acetylcholine is synthesized by cultured mammalian glial cells identified by cell-type specific markers. Primary cultures of rat brain astrocytes or microglia contained 2.0 and 1.6 pmol acetylcholine/10(6) cells on average respectively. Astrocyte cultures established from neonatal mouse brain contained even more acetylcholine (about 80 pmol acetylcholine/10(6) cells). Primary cultures of rat brain astrocytes showed choline acetyltransferase (ChAT) enzyme activity of 3 nmol/mg protein/h; ChAT activity was blocked by 10 microM bromoacetylcholine. In conclusion, these data demonstrate the synthesis of the "neurotransmitter" acetylcholine in cultured gli…
Acetylcholine in isolated airways of rat, guinea pig, and human: species differences in role of airway mucosa
1996
Stored endogenous acetylcholine (ACh) and in vitro synthesis of [3H]ACh were measured in isolated, mucosa-intact and mucosa-denuded airways of rat, guinea pig, and humans. In addition, choline acetyltransferase (ChAT) activity and ACh content were measured in freshly isolated airway mucosa as well as in cultured epithelial cells of rat tracheas. Rat tracheas stored 25 nmol/g ACh, whereas guinea pig tracheas and human bronchi contained only 2-3 nmol/g ACh. When incubated with [3H]choline, the isolated airways of rat, guinea pig, and human synthesized significant amounts of [3H]ACh. In guinea pig and human airways, removal of the mucosa affected neither stored ACh nor in vitro synthesis of […
Non-neuronal acetylcholine, a signalling molecule synthezised by surface cells of rat and man.
1997
Acetylcholine acts as a prominent transmitter in the central and peripheral nervous system. The aim of the present study was to investigate whether mammalian non-neuronal cells can synthesize and store acetylcholine. A cotton tipped applicator (Q-tip) was used to collect surface cells from airways and alimentary tract. Histological inspection indicated that rubbing of the luminal surface of human bronchi did not penetrate the basal membrane. Acetylcholine was measured by an HPLC-method using substrate-specific enzyme reactor-columns. Non-neuronal acetylcholine was found in cells covering inner and outer surfaces of rat and man. For example, acetylcholine was detected in the surface epitheli…