PubMed · 6897975
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
J A Romankiewicz. 1980. Vasoactive agents.. https://pubmed.ncbi.nlm.nih.gov/6897975/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Using fused-silica optical fibres for fluorescence light collection and bandpass filters for selection of emission wavelengths, a capillary electrophoresis detection cell of a conventional, tunable UV-Vis absorbance detector was adapted for simultaneous fluorescence (at selected emission wavelength) and absorbance (at selected excitation wavelength) detection. Detector performance is demonstrated with the monitoring of underivatized fluorescent compounds in body fluids by micellar electrokinetic capillary chromatography with direct sample injection. Compared with UV absorption detection, fluorescence detection is shown to provide increased selectivity and for selected compounds also up to tenfold higher sensitivity. Examples studied include screening for urinary indole derivatives (tryptophan, 5-hydroxytryptophan, tyrosine, 3-indoxyl sulfate and 5-hydroxyindole-3-acetic acid) and catecholamine metabolites (homovanillic acid and vanillylmandelic acid) and the monitoring of naproxen in serum, quinidine in serum and urine and of salicylate and its metabolites in serum and urine.
Estrogens and thyroid hormones contribute importantly to cell proliferation and tumor transformation in the pituitary gland. The purpose of the present article is provide review about neurotransmitters, chemicals, and receptors that are involved in estrogen-induced anterior pituitary growth. Central dopaminergic and noradrenergic systems are thought to be the most important systems in regulation of pituitary growth and function. For this purpose authors discuss some of their past and present data suggesting that estrogen-induced anterior pituitary pituitary growth is associated with decreased synthesis and metabolism of central catecholamines and increased adenohypophyseal dopamine 2 receptors. Treatment with thyroid hormones prevents both estrogen-induced catecholaminergic inhibition and dopamine D2 receptor increment in the anterior pituitary gland. Further studies focusing on central catecholaminergic systems, pituitary receptor equipment and mechanisms of intracellular signal transduction will be of value to better understand pituitary tumor formation and possibly to find new approaches toward treating patients with these tumors.
Platelet function is dynamically regulated in vivo, and stress or exercise may have prothrombotic effects due to platelet activation. Platelets are intimately involved in primary hemostasis and it is possible that platelet activation may be a link between stress and myocardial infarction via several mechanisms--neuro-hormonal activation, increased shear stress, and an increased risk for plaque rupture with ensuing platelet activation. Catecholamines and stress may overcome the platelet inhibition afforded by aspirin, which may limit its efficacy in preventing myocardial infarction. Lipid lowering therapy would be expected to attenuate platelet activation, but results to the contrary are presented. New and more efficient platelet inhibitors may antagonize also stress induced platelet activation and be more efficient in the prevention of thrombotic complications, but their greater efficacy also entail a greater risk for bleeding complications.