Expression Pattern of 5-HT (Serotonin) Receptors during Normal Development of the Human Spinal Cord and Ganglia and in Fetus with Cervical Spina Bifida

Abstract

The expression of 5-HT (serotonin) receptors (sr) was analyzed in the spinal cord and ganglia of 15 human conceptuses (5–10-weeks), and in the 9-week fetus with spina bifida. We used immunohistochemical method to detect sr-positive, apoptotic (caspase-3) and proliferating (Ki-67) cells, double immunofluorescence for co-localization with protein gene peptide (pgp) 9.5 and GFAP, as well as semiquantification and statistical measurements. Following the neurulation process, moderate (sr1 and sr2) and mild (sr3) expression characterized neuroblasts in the spinal cord and ganglia. During further development, sr1 expression gradually increased in the motoneurons, autonomic and sensory neurons, while sr2 and sr3 increased strongly in floor and roof plates. In the ganglia, sr3 expression increased during limited developmental period, while sr1 and sr2 increased throughout the investigated period. Co-expression of sr/pgp 9.5 characterized developing neurons, while sr/GFAP co-localized in the roof plate. In the spinal cord and ganglia of malformed fetus, weaker sr1 and sr2 and stronger sr3 expression accompanied morphological abnormalities. Anomalous roof plate morphology showed an excess of apoptotic and proliferating cells and increased sr3 expression. Our results indicate a human-species specific sr expression pattern, and the importance of sr1 in neuronal differentiation, and sr2 and sr3 in the control of the roof plate morphogenesis in normal and disturbed development.

Differences in Immunohistochemical and Ultrastructural Features between Podocytes and Parietal Epithelial Cells (PECs) Are Observed in Developing, Healthy Postnatal, and Pathologically Changed Human Kidneys

“…The area under the curve (AUC) of the fluorescence intensity histograms was used to quantify protein expression. The AUC analysis routine in GraphPad Prism 9.3.1 software (Graph Pad, La Jolla, CA, USA) was used to calculate AUCs [ 69 ]. Afterwards, AUC values were divided by the number of rectangular areas used for each particular figure in order to allow the comparison between different groups of samples.…”

The Distribution of Innervation and Immune Cell Infiltration Is Different in Genital and Extragenital Variants of Lichen Sclerosus

“…Information about all patients’ age was gathered, as well as the time from disease onset and the level of itch measured with a visual analog scale (VAS) for patients with LS. Tissues were processed as we have previously described [ 24 ]. Briefly, the tissues were fixed in 4% paraformaldehyde in phosphate-buffered saline (PBS), dehydrated in graded ethanol solutions up to 100%, paraffin-embedded, serially cut as 5 µm thick sections, and mounted on glass slides.…”

Serotonergic Modulation of Neurovascular Transmission: A Focus on Prejunctional 5-HT Receptors/Mechanisms

“…5-HT 1/2/3 receptors are highly active during motor, sensory, and autonomic neuron development [46]. Thus, these receptors may maintain homeostatic functions in the motor, sensory, and autonomic neurons of the developed organism.…”

“…From a global perspective, 5-HT is an amphibaric agent, and its actions on haemodynamic parameters are complex, depending on the experimental conditions [3,7]. This may be explained in terms of the numerous sites of action to 5-HT, which include: (i) the CNS; (ii) autonomic ganglia; (iii) perivascular autonomic and sensory nerve terminals; (iv) endothelial cells; (v) smooth muscle cells; and (vi) the heart [3,37,38,46,126,127]. Consequently, rather than assigning a single cardiovascular function to 5-HT, it is clear that 5-HT exerts multiple cardiovascular actions, which may be further complicated by pathophysiological states including, but not limited to, hypertension [3,7], depression [128], and pain [128].…”