An immunocytochemical study of calbindin-D28K in laminae I and II of the dorsal horn and spinal ganglia in the chicken with special reference to the relation to substance P-containing primary afferent neurons

Abstract

The localization of calbindin-D28K (CB) was studied immunocytochemically in laminae I and II of the dorsal horn and in spinal ganglia in the chicken, and compared with the distribution of substance P (SP) using double immunolabeling. At the light microscopic level, CB immunoreactivity was observed most intensely in the lamina II using the avidin-biotinylated peroxidase complex (ABC) and immunofluorescence methods. At the electron microscopic level using the ABC method, CB immunoreactivity was observed in the following three neuronal elements: 1) the scalloped central terminal with many dense-cored vesicles (DCVs) in the synaptic glomerulus; 2) some vesicle-containing dendrites (VCDs) inside or outside the synaptic glomerulus; and 3) some axon terminals outside the synaptic glomerulus. The CB-immunoreactive (IR) VCDs in the synaptic glomerulus often formed reciprocal synapses with the central terminal. Strong immunoreactivity was observed at the postsynaptic membrane of CB-IR elements. Double immunofluorescence and immunolabeling methods at the electron microscopic level showed that CB and SP colocalized in the scalloped central terminal with DCVs of the synaptic glomerulus. Almost all SP-IR neurons in the spinal ganglion revealed the coexistence of CB in serial sections in the chicken. In light of previous biochemical and physiological reports, our findings suggest that CB - coexisting with SP - plays an important role in the control of pain transmission through its strong Ca(2+)-buffering action in the chicken.

Immunohistochemical Localization of Calbindin-D28k and Calretinin in the Spinal Cord of Lungfishes

“…The first point to consider is that lungfishes have no brachial or pelvic enlargements that delineate variations in the external morphology of the spinal cord and that although we found slight differences in the numbers of cells for each immunoreactive population along the spinal cord, these differences do not represent a noticeable rearrangement in their distribution, as seen in tetrapods where marked differences in lumbar and cervical segments have been reported [Lunam, 1989;Yamamoto et al, 1989;Antal et al, 1990;Yoshida et al, 1990;Résibois and Rogers, 1992;Antal and Polgár, 1993;Ren et al, 1993;Ren and Ruda, 1994;Li et al, 2005;Morona et al, 2006aMorona et al, , b, 2007.…”

Tetrodotoxin induced changes in the chemical coding of dorsal root ganglion neurons supplying the porcine urinary bladder

“…It has also been found in a subpopulation of medium-or small-sized muscle and visceral nociceptors (Honda 1995). Numerous CB-containing small-or medium-sized DRG neurons also contained SP (Li et al 2005), what strongly suggests, that CB may be involved in some aspects of pain transmission, at least in small spinal ganglion neurons.…”

The influence of resiniferatoxin on the chemical coding of neurons in dorsal root ganglia supplying the urinary bladder in the female pig

“…CB was previously found in medium-or small-sized DRG neurons, mostly in a subpopulation of muscle and visceral nociceptors (Honda 1995). Numerous CB-containing small-or medium-sized DRG neurons also contained SP and co-expressed vanilloid receptor type 1 (Li et al 2005). This strongly suggests that CB is involved in some aspects of pain transmission.…”