PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-3 (3)
 

Clipboard (0)
None

Select a Filter Below

Journals
Authors
more »
Year of Publication
Document Types
1.  Evaluation of Thioperamide Effects Using Rat's Trachea Model 
Objectives
Thioperamide is used as an antagonist to the histamine H3 receptor. During administration of the drug, the trachea may be affected via nasal or oral inhalation. This study was to determine the effects of thioperamide on the trachea of rats in vitro.
Methods
We tested the effectiveness of thioperamide on isolated rat trachea submersed in Kreb's solution in a muscle bath. Changes in tracheal contractility in response to the application of parasympathetic mimetic agents were measured. The following assessments of thioperamide were performed: 1) effect on tracheal smooth muscle resting tension; 2) effect on contraction caused by 10-6 M methacholine as a parasympathetic mimetic; 3) effect of the drug on electrically-induced tracheal smooth muscle contractions.
Results
Thioperamide induced a significant relaxation response at a preparation concentration up to 10-4 M. The drug also inhibited the electrical field stimulation induced spike contraction. However, thioperamide alone had a minimal effect on the basal tension of the trachea at increasing concentrations.
Conclusion
The study indicated that high concentrations of thioperamide might actually antagonize cholinergic receptors and block parasympathetic function of the trachea.
doi:10.3342/ceo.2013.6.1.12
PMCID: PMC3604264  PMID: 23526076
Trachea; Asthma; In vitro; Thioperamide
2.  Effects of cromolyn sodium on isolated rat's trachea 
Allergy & Rhinology  2011;2(2):e46-e50.
Cromolyn sodium (cromolyn) effectively inhibits both antigen- and exercise-induced asthma when used as an aerosol. Intranasal cromolyn is also recommended for preventing and treating allergic rhinitis. By inhibiting the degranulation of sensitized mast cells, cromolyn reduces the release of mediators that trigger inflammation and the allergic response. The precise pharmacologic activity of cromolyn has not been fully elucidated. This study evaluated the effect of cromolyn on isolated rat's trachea. The following assessments of cromolyn were performed: (1) effect on tracheal resting tension, (2) effect on contraction caused by 10−6 M of methacholine as a parasympathetic mimetic, and (3) effect of the drug on electrically induced tracheal contractions. The results indicated cromolyn could inhibit electrical field stimulation-induced spike contraction when the preparation was increased to 10−4M. Adding cromolyn at doses of ≥10−8 M did not elicit a relaxation or contraction response to 10−6 M of methacholine-induced contraction. It alone had a minimal effect on the basal tension of the trachea as the concentration increased. This study indicates cromolyn had no cholinergic or anticholinergic effect and high concentrations of cromolyn might actually inhibit parasympathetic function of the trachea. Inhibiting parasympathetic function of the trachea through stabilizing the presynaptic nerve by cromolyn may be responsible for protecting patients against antigen- and exercise-induced asthma.
doi:10.2500/ar.2011.2.0015
PMCID: PMC3390115  PMID: 22852116
Cromolyn; in vitro study smooth muscle; trachea
3.  Implantation of olfactory ensheathing cells promotes neuroplasticity in murine models of stroke 
The Journal of Clinical Investigation  2008;118(7):2482-2495.
Murine olfactory ensheathing cells (OECs) promote central nervous system axonal regeneration in models of spinal cord injury. We investigated whether OECs could induce a neuroplastic effect to improve the neurological dysfunction caused by hypoxic/ischemic stress. In this study, human OECs/olfactory nerve fibroblasts (hOECs/ONFs) specifically secreted trophic factors including stromal cell–derived factor–1α (SDF-1α). Rats with intracerebral hOEC/ONF implantation showed more improvement on behavioral measures of neurological deficit following stroke than control rats. [18F]fluoro-2-deoxyglucose PET (FDG-PET) showed increased glucose metabolic activity in the hOEC/ONF-treated group compared with controls. In mice, transplanted hOECs/ONFs and endogenous homing stem cells including intrinsic neural progenitor cells and bone marrow stem cells colocalized with specific neural and vascular markers, indicating stem cell fusion. Both hOECs/ONFs and endogenous homing stem cells enhanced neuroplasticity in the rat and mouse ischemic brain. Upregulation of SDF-1α and CXCR4 in hOECs/ONFs promoted neurite outgrowth of cocultured primary cortical neurons under oxygen glucose deprivation conditions and in stroke animals through upregulation of cellular prion protein (PrPC) expression. Therefore, the upregulation of SDF-1α and the enhancement of CXCR4 and PrPC interaction induced by hOEC/ONF implantation mediated neuroplastic signals in response to hypoxia and ischemia.
doi:10.1172/JCI34363
PMCID: PMC2398740  PMID: 18596986

Results 1-3 (3)