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Sensory, motor and sympathetic neurons forming the common peroneal and tibial nerves in the macaque monkey (Macaca fascicularis)

Janjua MZ, Leong SK

J Anat, 1987 Aug;153:63-76.
PMID: 3429328

The motoneurons, dorsal root ganglion (DRG) and sympathetic ganglion (SG) cells forming the common peroneal (CPN) and tibial (TN) nerves of young and semiadult monkeys (Macaca fascicularis) were localised by the horseradish peroxidase method of tracing neuronal connections. The motoneurons forming the CPN occur in the L4-L6 segments, appearing as 1-3 groups and occupying the retroposterolateral (rpl), posterolateral (pl) and central (c) groups of motor nuclei. The motoneurons forming the TN occur in the L4-L7 segments, appearing as 1-4 groups and occupying the rpl, pl, c and anterolateral (al) groups. The motoneurons and DRG cells forming the CPN show peak frequencies at the L5 level, and the SG cells forming the same nerve, at the L6 level in most cases. The motoneurons and DRG cells forming the TN show peak frequencies at the L6 level and the SG cells forming the same nerve, also at the L6 level in most cases. The bulk of motoneurons, DRG and SG cells forming the CPN and TN are concentrated in two segmental levels. For CPN the motoneurons measure between 14-76 micron in their average somal diameters and for TN, 16-70 micron. The majority of them (65.5% for CPN motoneurons and 72% for TN motoneurons) have average somal diameters greater than 38 micron. The size spectrum of the DRG cells forming the CPN is similar to that of DRG cells forming the TN, being 12-78 micron for CPN and 10-76 micron for TN. The sympathetic neurons forming the CPN (measuring 10-44 micron) have a larger size spectrum than those forming the TN (measuring 6-33 micron). The diameter spectrum (3-20 micron for TN and 2-19 micron for CPN) and peak frequency distributions (10 micron for both TN and CPN) of the myelinated fibres present in the CPN and TN are also similar, with the CPN fibres skewing towards a slightly larger size. Many of the fibres in the young and semi-adult monkeys are not yet myelinated.

Matched MeSH terms: Ganglia, Sympathetic/anatomy & histology
Thoracic sympathetic ganglion blocks: real-world outcomes in 207 chronic pain patients

Kim J, Yun M, Han AH, Pauzi MF, Jeong JH, Yoo Y, et al.

Reg Anesth Pain Med, 2024 Jul 08;49(7):528-535.
PMID: 37726196 DOI: 10.1136/rapm-2023-104624

BACKGROUND: Thoracic sympathetic ganglion block (TSGB) is a procedure to manage sympathetically maintained upper extremity pain (sympathetically maintained pain). To date, only a few studies have evaluated the clinical effectiveness of TSGB in pain medicine. This study investigated (1) the relationship between technical success of TSGB and pain reduction in patients with chronic upper extremity pain and (2) relevant clinical factors for a positive TSGB outcome.
METHODS: We retrospectively reviewed medical data in 232 patients who received TSGB from 2004 to 2020. Technical success and a positive outcome of TSGB were defined as a temperature increase of ≥1.5°C at 20 min and a pain reduction with ≥2 points on the 11-point Numerical Rating Scale at 2 weeks post-TSGB, respectively. Correlations were assessed using correlation coefficients (R), and multivariable regression model was used to identify factors relevant to TSGB outcomes.
RESULTS: 207 patients were ultimately analyzed; among them, 115 (55.5%) patients positively responded to TSGB, and 139 (67.1%) achieved technical success after TSGB. No significant relationship existed between the pain reduction and the temperature increase after TSGB (R=0.013, p=0.855). Comorbid diabetes (OR 4.200) and adjuvant intake (OR 3.451) were positively associated, and psychiatric comorbidity (OR 0.327) and pain duration (OR 0.973) were negatively associated with TSGB outcome.
CONCLUSIONS: We found no significant association between the temperature increase and pain reduction after TSGB. Further studies are warranted to identify significant factors associated with TSGB outcomes in patients with complex regional pain syndrome and neuropathic pain diseases.

Matched MeSH terms: Ganglia, Sympathetic*
Hydralazine administration activates sympathetic preganglionic neurons whose activity mobilizes glucose and increases cardiovascular function

Parker LM, Damanhuri HA, Fletcher SP, Goodchild AK

Brain Res, 2015 Apr 16;1604:25-34.
PMID: 25662772 DOI: 10.1016/j.brainres.2015.01.049

Hypotensive drugs have been used to identify central neurons that mediate compensatory baroreceptor reflex responses. Such drugs also increase blood glucose. Our aim was to identify the neurochemical phenotypes of sympathetic preganglionic neurons (SPN) and adrenal chromaffin cells activated following hydralazine (HDZ; 10mg/kg) administration in rats, and utilize this and SPN target organ destination to ascribe their function as cardiovascular or glucose regulating. Blood glucose was measured and adrenal chromaffin cell activation was assessed using c-Fos immunoreactivity (-ir) and phosphorylation of tyrosine hydroxylase, respectively. The activation and neurochemical phenotype of SPN innervating the adrenal glands and celiac ganglia were determined using the retrograde tracer cholera toxin B subunit, in combination with in situ hybridization and immunohistochemistry. Blood glucose was elevated at multiple time points following HDZ administration but little evidence of chromaffin cell activation was seen suggesting non-adrenal mechanisms contribute to the sustained hyperglycemia. 16±0.1% of T4-T11 SPN contained c-Fos and of these: 24.3±1.4% projected to adrenal glands and 29±5.5% projected to celiac ganglia with the rest innervating other targets. 62.8±1.4% of SPN innervating adrenal glands were activated and 29.9±3.3% expressed PPE mRNA whereas 53.2±8.6% of SPN innervating celiac ganglia were activated and 31.2±8.8% expressed PPE mRNA. CART-ir SPN innervating each target were also activated and did not co-express PPE mRNA. Neurochemical coding reveals that HDZ administration activates both PPE+SPN, whose activity increase glucose mobilization causing hyperglycemia, as well as CART+SPN whose activity drive vasomotor responses mediated by baroreceptor unloading to raise vascular tone and heart rate.

Matched MeSH terms: Ganglia, Sympathetic/cytology; Ganglia, Sympathetic/drug effects*; Ganglia, Sympathetic/metabolism
Fulltext Interactions of noncanonical motifs with hnRNP A2 promote activity-dependent RNA transport in neurons

Muslimov IA, Tuzhilin A, Tang TH, Wong RK, Bianchi R, Tiedge H

J. Cell Biol., 2014 May 26;205(4):493-510.
PMID: 24841565 DOI: 10.1083/jcb.201310045

A key determinant of neuronal functionality and plasticity is the targeted delivery of select ribonucleic acids (RNAs) to synaptodendritic sites of protein synthesis. In this paper, we ask how dendritic RNA transport can be regulated in a manner that is informed by the cell's activity status. We describe a molecular mechanism in which inducible interactions of noncanonical RNA motif structures with targeting factor heterogeneous nuclear ribonucleoprotein (hnRNP) A2 form the basis for activity-dependent dendritic RNA targeting. High-affinity interactions between hnRNP A2 and conditional GA-type RNA targeting motifs are critically dependent on elevated Ca(2+) levels in a narrow concentration range. Dendritic transport of messenger RNAs that carry such GA motifs is inducible by influx of Ca(2+) through voltage-dependent calcium channels upon β-adrenergic receptor activation. The combined data establish a functional correspondence between Ca(2+)-dependent RNA-protein interactions and activity-inducible RNA transport in dendrites. They also indicate a role of genomic retroposition in the phylogenetic development of RNA targeting competence.

Matched MeSH terms: Ganglia, Sympathetic/cytology