Subpopulations of Calbindin-, Calretinin-, and Parvalbumin-Immunoreactive Interneurons in the Dorsal Horn of the Spinal
- PDF / 4,324,589 Bytes
- 5 Pages / 594 x 792 pts Page_size
- 30 Downloads / 186 Views
Subpopulations of Calbindin-, Calretinin-, and ParvalbuminImmunoreactive Interneurons in the Dorsal Horn of the Spinal Cord in Female C57BL/6 Mice V. V. Porseva,1 A. I. Emanuilov,2 and P. M. Maslyukov3
UDC 611.822.2
Translated from Morfologiya, Vol. 157, No. 1, pp, 18–23, January–February, 2020. Original article submitted January 13, 2018. Revised version received November 18, 2019. Objective. To conduct a comparative analysis of subpopulations of interneurons containing calbindin (CAB), calretinin (CAR), and parvalbumin (PAV) in the dorsal horn of segments T3–T5 of the spinal cord (SC). Materials and methods. Immunoreactive (IR) interneurons were studied in female C57BL/6 mice aged 16 weeks using immunohistochemical methods. Results. All IR-interneuron subpopulations were topographically detected in all laminae of the dorsal horn of the SC, though PAV-IR interneurons were not detected in lamina I. The content of CAB interneurons dominated in laminae I (27%) and II (29%), CAR interneurons in lamina II (21.5%), and PAV interneurons in laminae IV (5.7%) and V (6.2%). In addition, the PAV interneuron subpopulation consisted of a smaller group of cells than those of the other calcium-binding proteins in laminae II and III and the medial border (MB) of the dorsal horn, while CAR interneurons were a smaller group in laminae III, IV, and V and the MB. Quantitatively, calbindin-containing interneuron subpopulations dominated in all laminae of the dorsal horn of the SC. Cell sizes in these subpopulations of IR interneurons were statistically significantly different – CAB- and CAR-containing interneurons being larger and PAV-containing cells being smaller. Conclusions. Different subpopulations of interneurons immunoreactive to calbindin, calretinin, and parvalbumin were found in the dorsal horn of the SC and were specific to each lamina. Keywords: interneuron, dorsal horn, spinal cord, immunohistochemistry.
Introduction. Calcium ions are universal intracellular messengers and play a leading role in controlling a variety of neuronal processes [4, 10, 11]. The intracellular calcium-binding proteins most widespread in the central and peripheral nervous system in different animal species selectively expressed in specific interneuron populations are calbindin (CAB), molecular weight 28 kDa, calretinin (CAR), and parvalbumin (PAV) [2, 3, 6, 7, 9].
Cells containing CAB, CAR, and PAV are present in all laminae of the dorsal horn of the spinal cord (SC) [2–4, 7], but there are differences in the levels of expression of calcium-binding proteins, particularly in terms of the larger number of CAB-containing interneurons in the lumbar segments of adult male mice [2], rats [3], and cats [7] as compared with the cervical segments (C6–C7) [3], the superior (T2) [2], and mid (T6–T8) [3] thoracic and the sacral (S1–S3) segments of the SC [7]. The heterogeneity of the gray matter of the SC is apparent not only in the rostrocaudal direction, but also the ventrodorsal. Groups of interneurons receiving spikes of different modalities [2, 4, 5,
Data Loading...
