Search results for "Site of action"
showing 5 items of 5 documents
Rational Species Extrapolation of Toxic Effects
1994
One of the main problems in toxicology and pharmacology is the extrapolation from one species to another, particularly from laboratory animals to man or in ecotoxicology from laboratory animals to free living species. Many toxicological data were raised only in one or a few species of laboratory animals. In the last decades more and more experimental data were obtained from in vitro-systems. Therefore extrapolations from in vitro to in vivo and from species to species are required. Species differences in uptake, distribution, metabolism, site of action, elimination and accumulation have to be taken into account. Most foreign compounds are metabolically transformed by diverse xenobiotica met…
Tricks and Tracks in the Identification and Quantification of Endocannabinoids
2013
Abstract The endocannabinoid system serves pivotal roles in a diverse range of physiological and pathophysiological states, including behavior, pain, schizophrenia, obesity, Alzheimer disease, multiple sclerosis and cardiovascular disease. A number of endocannabinoids (eCBs) and their receptors have been characterised and identified in a plethora of biological matrices. The eCBs include N-arachidonoyl ethanolamine (anandamide), 2-arachidonoyl glycerol, 2-arachidonoyl glyceryl ether (noladin ether), O-arachidonoyl ethanolamine (virodhamine) and N-arachidonoyl dopamine. Advanced targeted mass spectrometry methods, particularly the selected reaction monitoring, has facilitated sensitive quanti…
Controlling the semi-permeability of protein nanocapsules influences the cellular response to macromolecular payloads.
2021
Nanocapsules are an excellent platform for the delivery of macromolecular payloads such as proteins, nucleic acids or polyprodrugs, since they can both protect the sensitive cargo and target its delivery to the desired site of action. However, the release of macromolecules from nanocapsules remains a challenge due to their restricted diffusion through the nanoshell compared to small molecule cargo. Here, we designed degradable protein nanocapsules with varying crosslinking densities of the nanoshell to control the release of model macromolecules. While the crosslinking did not influence the degradability of the capsules by natural proteases, it significantly affected the release profiles. F…
Fetal Renal Effects of Intrauterine Diuretic Application in Wistar Rats
1987
The application of placenta-permeable diuretics in the pregnant woman has been the subject of controversial discussion (Friedberg 1980; Souster and Emery 1980). Not only is the fetus endangered by potential placental ischaemia, natrium and potassium loss and possible dehydration in the mother (Friedberg 1980; Gant and Madden 1975), but also induced effects on fetal organ formation should be considered (Frohneberg and Hutschenreiter 1982; Seufert 1986). Depending on the site of action and placental permeability, fetal urine production can be increased (Wladimiroff 1975), thus leading to consequences for the morphological and functional embryogenesis of isolated nephron sections (Frohneberg 1…
On the Retention of Diuretics in Micellar Liquid Chromatography and Their Site of Action Within the Nephron
1993
Abstract The therapeutical action of diuretics has been attributed to their hydrophobic character, among other properties. Therapeutical and physiological classifications of diuretics are correlated. The site of action of high efficacay diuretics is the loop of Henle, that of intermediate efficacy diuretics is the distal tubule and that of low efficacy diuretics is the proximal and distal tubules, and the collecting duct. Partition coefficients between water and micelles offer a scale for hydrophobicity, which leads to a further correlation between retention in Micellar Liquid Chromatography (MLC), with a sodium dodecyl sulphate mobile phase and an ODS-C18 column, and the sites of action wi…