Evaluation of plasma norepinephrine as an index of sympathetic neuron function in the conscious, unrestrained rat

Micalizzi, Edwin R.; Pals, Donald T.

doi:10.1016/0024-3205(79)90080-8

Cited by 64 publications

(18 citation statements)

References 13 publications

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“…Such a tendency might suggest a variable amount of compensatorily increased adrenomedullary secretion in response to decreased sympathetic noradrenergic innervation. Consistent with this explanation, chemical sympathectomy produced by 6-hydroxydopamine is associated with elevated plasma EPI concentrations [19].…”

Section: Discussionmentioning

confidence: 85%

Plasma Catechols in Familial Dysautonomia: A Long-term Follow-up Study

2008

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This study tested whether familial dysautonomia (FD) involves progressive loss of noradrenergic nerves. Plasma levels of catechols, including dihydroxyphenylglycol (DHPG), norepinephrine (NE), dopamine (DA), and DOPA, were measured in 7 adult patients with FD and 50 healthy control subjects. FD patients were re-tested after a mean follow-up period of 13 years. Compared to controls, FD patients had low plasma levels of DHPG (P < 0.001), high DOPA and DA levels (P = 0.01, P = 0.0002), and high NE:DHPG (P < 0.0001), DA:NE (P = 0.0003), and DOPA:DHPG (P < 0.0001) ratios. At follow-up there were no changes in plasma levels of individual catechols; however, there were further increases in DOPA:DHPG ratios (mean 24 ± 7%, P = 0.01). In FD, plasma catechol profiles are sufficiently stable, at least over a decade, to be used as a biomarker of disease involvement. An increasing DOPA:DHPG ratio suggests slight but consistent, progressive loss of noradrenergic neurons.

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Section: Discussionmentioning

confidence: 85%

Plasma Catechols in Familial Dysautonomia: A Long-term Follow-up Study

2008

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“…ificantly differ-1978; Micalizzi & Pals, 1979 Rascher et al, 1982) and it is possible that a similar plasma noradmechanism operates in rats with ARF.…”

Section: Discussionmentioning

confidence: 99%

Cardiovascular responses in rats with glycerol‐induced acute renal failure

Bowmer¹,

Warren²,

Yates³

1983

British J Pharmacology

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“…The splanchnic adrenal innervation (which includes the sympathoadrenomedullary innervation) regulates adrenocortical sensitivity to ACTH stimulation, because sectioning the splanchnic nerve decreases the adrenal response to ACTH [51, 52] whereas stimulation augments it [53, 54]. Stressful stimuli are also known to activate the sympathetic nervous system resulting in rapid increases in circulating adrenaline, stemming mainly from chromaffin cells in the adrenal medulla, and noradrenalin, released largely from the neuro-sympathetic system [55,56,57,58]. Furthermore, and of relevance for the differential glucocorticoid responses to stress in the exercised rats, stressors that are physically demanding such as forced swimming evoke much larger increases in adrenaline than psychological challenges such as novel cage stress which are hardly physically demanding [59,60,61,62].…”

Section: Discussionmentioning

confidence: 99%

Voluntary Exercise Impacts on the Rat Hypothalamic-Pituitary-Adrenocortical Axis Mainly at the Adrenal Level

Droste

Chandramohan²,

Hill³

et al. 2007

Neuroendocrinology

134

143

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Introduction: Evidence is accumulating that the regular performance of exercise is beneficial for stress coping. However, the hypothalamic-pituitary-adrenocortical (HPA) axis of voluntarily exercising rats has never been comprehensively investigated. Methods: Therefore, male Sprague-Dawley rats were given access to a running wheel in their home cage for 4 weeks in which they ran 4–7 km per night. Results: After 4 weeks, the exercising animals showed significantly less body weight gain, less abdominal fat tissue, decreased thymus weight, and increased adrenal weight (relative to body weight). Furthermore, tyrosine hydroxylase (TH) mRNA levels were selectively increased in the right adrenal me- dulla indicating an increase in sympathoadrenomedullary capacity in exercising rats. No changes were observed in paraventricular corticotropin-releasing hormone (CRH), arginine-vasopressin (AVP) and oxytocin mRNA levels. Mineralocorticoid receptor (MR) mRNA levels in hippocampus and glucocorticoid receptor (GR) mRNA levels in frontal cortex, parvocellular paraventricular nucleus and anterior pituitary were unchanged, whereas GR mRNA levels were increased in distinct hippocampal cell layers. Early morning baseline levels of plasma ACTH and corticosterone were similar in both groups. Interestingly, the response to different stressful stimuli (e.g. forced swimming, novelty) revealed that the exercising rats showed stressor-specific changes in HPA hormone responses. Forced swimming evoked a markedly enhanced response in corticosterone levels in the exercising rats. In contrast, if rats were exposed to a novel environment, exercising rats showed a much lower response in corticosterone than the control animals. However, the response in ACTH to either stressor was comparable between groups. Thus, in exercising rats physically demanding stressors evoke enhanced glucocorticoid responses whereas mild psychologically stressful stimuli such as novelty result in an attenuated glucocorticoid response. Interestingly, this attenuated hormone response corresponded with the observation that the exercising rats showed less anxious behaviour in the novelty situation. Conclusions: The differential responses in plasma corticosterone levels to different types of stress in the face of comparable responses in ACTH levels underscore the existence of critical regulatory control mechanisms at the level of the adrenal gland. We have hypothesized that changes in the sympathoadrenomedullary input may play an important role in these distinct glucocorticoid responses to stress. Our previous studies have shown similar changes in voluntarily exercising mice. Therefore, we conclude that the effects of exercise on the organism are not species-specific. Thus, our observations may have translational implications for the human situation.

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Evaluation of plasma norepinephrine as an index of sympathetic neuron function in the conscious, unrestrained rat

Cited by 64 publications

References 13 publications

Plasma Catechols in Familial Dysautonomia: A Long-term Follow-up Study

Plasma Catechols in Familial Dysautonomia: A Long-term Follow-up Study

Cardiovascular responses in rats with glycerol‐induced acute renal failure

Voluntary Exercise Impacts on the Rat Hypothalamic-Pituitary-Adrenocortical Axis Mainly at the Adrenal Level

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