Sympathectomy alters homeostasis: chronic interference with β-adrenergic receptors (via either sympathectomy or β-blockade) on cardiac mast cell morphology/activation and on interstitial collagen deposition

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chronic interference with β-adrenergic receptors (via either sympathectomy or β-blockade) on cardiac mast cell morphology/activation and on interstitial collagen deposition

In the present study we investigated the effects of chronic interference with β-adrenergic receptors (via either sympathectomy or β-blockade) on cardiac mast cell morphology/activation and on interstitial collagen deposition. In rats subjected to chemical sympathectomizy with the neuro- toxin 6-hydroxydopamine (6-OHDA) we observed a significant increase of mast cell density, and in particular of degranulat- ing mast cells, suggesting a close relationship between the cardiac catecholaminergic system and mast cell activation. In parallel, chronic 6-OHDA treatment was associated with increased collagen deposition. The influence of the β-adren- ergic receptor component was investigated in rats subjected to chronic propranolol administration, that caused a further significant increase in mast cell activation associated with a lower extent of collagen deposition when compared to chem- ical sympathectomy. These data are the first demonstration of a close relationship between rat cardiac mast cell activation and the catecholaminergic system, with a complex interplay with cardiac collagen deposition. Specifically, abrogation of the cardiac sympathetic efferent drive by chemical sympathectomy causes mast cell activation and interstitial fibrosis, possibly due to the local effects of the neurotoxin 6-hydroxy- dopamine. In contrast, β-adrenergic blockade is associated with enhanced mast cell degranulation and a lower extent of collagen deposition in the normal myocardium. In conclusion, cardiac mast cell activation is influenced by β-adrenergic influences.

http://www.ejh.it/index.php/ejh/article/viewFile/985/1108

Correspondence: Rosanna Nano,

Department of Animal Biology, University of Pavia,

European Journal of Histochemistry

2006; vol. 50 issue 2 (Apr-Jun):133-140

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we conclude that the sympathetic nervous system influences the metabolic activity of the aorta

The effect of chemical sympathectomy with 6-hydroxydopamine (6-OH-DA) on collagen formation in the aortic wall was investigated in rabbits and rats. Eight weeks after 6-OH-DA treatment of rabbits, there was a significant increase an collagen content in aortas and histologic changes in the elastic elements within the media. The possibility of a direct effect of 6-OH-DA on connective tissue formation was investigated in a subsequent experiment in rats. The rates of collagen synthesis and prolyl hydroxylase activity (PHA) were determined in aortas and in the fibrotic granuloma around subcutaneously implanted polyvinylalcohol sponges. Rates of collagen synthesis and PHA were significantly increased in the aortas of 6-OH-DA treated rats, but not in fibrotic granuloma, confirming the changes seen in the aorta of rabbits and suggesting that 6-OH-DA does not directly affect collagen synthesis. We conclude that the sympathetic nervous system influences the metabolic activity of the aorta. Our data indicate that when the aortic wall is deprived of adrenergic nervous stimulation, changes occur which resemble those seen in natural aging of the aorta. It is plausible to assume that such a metabolic derangement in the vessel wall will make these vessels more vulnerable to additional stresses.

Experimental and Molecular Pathology
Volume 28, Issue 3, June 1978, Pages 279-289

sympathectomy affects the heart, sweating, and circulation

heart rate was significantly reduced at rest (14%), at sub-maximal exercise (12.3%), and at peak exercise (5.7%), together with a significant increase in oxygen pulse (11.8, 12.7, and 7.8%, respectively). The rate pressure product (RPP) was also significantly reduced following the surgical procedure at all three study stages, while all other physiological variables measured remained unchanged. It is suggested that thoracic-sympathetic denervation affects the heart, sweating, and circulation of the respective denervated region

Eur J Appl Physiol. 2008 Sep;104(1):79-86. Epub 2008 Jun 10.

sympathectomy interrupts neural messages to many different organs, glands and muscles

Surgical and chemical sympathectomy can alter cellular proliferation

Surgical denervation and chemical sympathectomy can alter cellular proliferation, B- and T-cell responsiveness and lymphocyte migration in lymphoid organs [17].

In vitro studies have shown that neuropeptides can have numerous effects, either inhibiting or stimulating the proliferation, differentiation and functions of immune cells [19]* Development of systemic lupus erythematosus in mice is associated with alteration of neuropeptide concentrations in inﬂamed kidneys and immunoregulatory organs

Neuroscience Letters 248 (1998) 97– 100

decreased conditioning-related activity in insula and amygdala after autonomic denervation

The degree to which perceptual awareness of threat stimuli and bodily states of arousal modulates neural activity associated with fear conditioning is unknown. We used functional magnetic neuroimaging (fMRI) to study healthy subjects and patients with peripheral autonomic denervation to examine how the expression of conditioning-related activity is modulated by stimulus awareness and autonomic arousal. In controls, enhanced amygdala activity was evident during conditioning to both "seen" (unmasked) and "unseen" (backward masked) stimuli, whereas insula activity was modulated by perceptual awareness of a threat stimulus. Absent peripheral autonomic arousal, in patients with autonomic denervation, was associated with decreased conditioning-related activity in insula and amygdala. The findings indicate that the expression of conditioning-related neural activity is modulated by both awareness and representations of bodily states of autonomic arousal.

http://www.ncbi.nlm.nih.gov/pubmed/11856537

second thoracic sympathetic ganglion was most commonly located (50%) in the second intercostal space

anatomic variations of the T2 nerve root

6 (9.1%) sides showed a single large ganglion formed by the stellate and the second thoracic sympathetic ganglia. The second thoracic sympathetic ganglion was most commonly located (50%) in the second intercostal space. Conclusion: The anatomic variations of the intrathoracic nerve of Kuntz and the second thoracic sympathetic ganglion were characterized in human cadavers. Journal of thoracic and cardiovascular surgery Y. 2002, vol. 123, No. 3, pages 498-501 [bibl. : 14 ref. http://www.refdoc.fr/Detailnotice?idarticle=9466218