Alpha2-and beta2-adrenoceptor downregulation in marathon runners

Schultz, Klaus-Detlev; Fritschka, Emanuel; Kribben, Andreas; Rothschild, Markus A.; Thiede, Hans-Michael; Distler, A.; Philipp, Thomas

doi:10.1097/00004872-198900076-00021

Cited by 8 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the surplus of catecholamines produces a down-regulation of the adrenoceptors. 144 The consequence of down-regulation of adrenoceptors is linked to a specific behaviour: the decrease in noradrenergic activity, in addition to endorphine production, causes the pleasant sensa-tion deriving from physical effort and reduces pathologic reactions to stress.…”

Section: Sensitivity and Inverse Effects P Bellavite Et Almentioning

confidence: 99%

Cell sensitivity, non-linearity and inverse effects

et al. 2015

View full text Add to dashboard Cite

It has been claimed that the homeopathic principle of 'similarity' (or 'similia') and the use of individualized remedies in extremely low doses conflicts with scientific laws, but this opinion can be disputed on the basis of recent scientific advances. Several mechanisms to explain the responsiveness of cells to ultra-low doses and the similarity as inversion of drug effects, have again been suggested in the framework of hormesis and modern paradoxical pharmacology. Low doses or high dilutions of a drug interact only with the enhanced sensitivities of regulatory systems, functioning as minute harmful stimuli to trigger specific compensatory healing reactions. Here we review hypotheses about homeopathic drug action at cellular and molecular levels, and present a new conceptual model of the principle of similarity based on allosteric drug action. While many common drugs act through orthostatic chemical interactions aimed at blocking undesired activities of enzymes or receptors, allosteric interactions are associated with dynamic conformational changes and functional transitions in target proteins, which enhance or inhibit specific cellular actions in normal or disease states. The concept of allostery and the way it controls physiological activities can be broadened to include diluted/dynamized compounds, and may constitute a working hypothesis for the study of molecular mechanisms underlying the inversion of drug effects.

show abstract

Section: Sensitivity and Inverse Effects P Bellavite Et Almentioning

confidence: 99%

Cell sensitivity, non-linearity and inverse effects

et al. 2015

View full text Add to dashboard Cite

show abstract

“… 13 Alpha-2 and beta-2 adrenoreceptor down-regulation has been demonstrated on platelets and lymphocytes of marathon runners in the presence of increased catecholamine levels. 14 …”

Section: Discussionmentioning

confidence: 99%

Profound bradycardia associated with NIV removal

Echevarria

Bourke

Gibson

2012

Respiratory Medicine Case Reports

View full text Add to dashboard Cite

A patient with lower-limb onset ALS presented with a one-month history of vasovagal episodes and a one-week history of cough productive of green sputum and lethargy. She was drowsy and in acute on chronic type-two respiratory failure. She responded to non-invasive ventilation, however she suffered recurrent episodes of profound bradycardia on removal of the mask, which gradually resolved over ten days. We have reviewed the literature and offer a potential explanation for these events.

show abstract

“…However, platelet 3-adrenoceptors evaluated by specific [3H]-yohimbine binding have been reported to show a significantly lower level in the patient presented chronic and stable high levels of plasma noradrenaline without any major change in adrenaline [45]. Furthermore, Schultz et a1 [44] reported that platelet a,-adrenoceptor density decreased after physical exercise, whereas both plasma noradrenaline and adrenaline concentrations increased. These findings reflect that increases in endogenous catecholamine concentrations cause down-regulation of a,-adrenoceptor densities on platelets.…”

Section: Discussionmentioning

confidence: 99%

Platelet and brain α₂‐adrenoceptors and cardiovascular sensitivity to agonists in dogs suffering from endotoxic shock

Hikasa

Fukui

Sato

et al. 1998

Fundamemntal Clinical Pharma

View full text Add to dashboard Cite

We examined the changes in alpha 2-adrenoceptor binding on platelet and brain membranes of dogs treated with a non-lethal dose of endotoxin (0.1 mg/kg intravenously), and the alpha 2-adrenoceptor mediated cardiovascular effects during endotoxin shock. At 2 h, 24 h, and 7 days after endotoxin administration, the number of binding sites (Bmax) of [3H]yohimbine binding decreased and equilibrium dissociation constants (Kd) increased in platelets, whereas both Bmax and Kd decreased in either cerebral cortex or medulla oblongata. After 30 days of endotoxin administration, there were no significant differences in Bmax or Kd between the treated and untreated animals in both platelets and brain tissues. Significant positive correlations were observed for Bmax values between platelets and brain tissues, although negative correlations for Kd values between platelets and brain were not significant. Significant negative correlations were also observed between plasma catecholamine concentrations and platelet alpha 2-adrenoceptor number, and between plasma noradrenaline and medulla alpha 2-adrenoceptor number. Pretreatment with E coli endotoxin diminished cardiovascular effects such as bradycardia, hypotension, and increase in systemic vascular resistance induced by either i.v. clonidine or xylazine. This suggests that alpha 2-adrenoceptor activity is impaired in the central nervous system as well as in the peripheral vascular system during endotoxin shock. Therefore, platelets may in part represent a good model which reflects the alpha 2-adrenoceptor changes in the central nervous system and peripheral vascular system during and after endotoxin shock.

show abstract

Alpha2-and beta2-adrenoceptor downregulation in marathon runners

Cited by 8 publications

References 0 publications

Cell sensitivity, non-linearity and inverse effects

Cell sensitivity, non-linearity and inverse effects

Profound bradycardia associated with NIV removal

Platelet and brain α₂‐adrenoceptors and cardiovascular sensitivity to agonists in dogs suffering from endotoxic shock

Contact Info

Product

Resources

About

Alpha2-and beta2-adrenoceptor downregulation in marathon runners

Cited by 8 publications

References 0 publications

Cell sensitivity, non-linearity and inverse effects

Cell sensitivity, non-linearity and inverse effects

Profound bradycardia associated with NIV removal

Platelet and brain α2‐adrenoceptors and cardiovascular sensitivity to agonists in dogs suffering from endotoxic shock

Contact Info

Product

Resources

About

Platelet and brain α₂‐adrenoceptors and cardiovascular sensitivity to agonists in dogs suffering from endotoxic shock