Parvalbumin is highly colocalized with calbindin D28k and rarely with calcitonin gene-related peptide in dorsal root ganglia neurons of rat

Sections of lumbar dorsal root ganglia from rat were analyzed by immunohistochemical techniques to determine the size distribution and numbers of cells containing parvalbumin and calbindin D28k and to establish their coexistence relationships with each other and with cells containing calcitonin gene-related peptide (CGRP). The proportion of ganglia cells containing parvalbumin and calbindin D28k was 14% and 22%, respectively. The majority of cells immunoreactive for these proteins were of the large A type. Parvalbumin was colocalized almost completely (greater than 99%) with with calbindin D28k and minimally (less than 1%) with CGRP. Only 9% of the calbindin D28k-positive cells were immunoreactive for CGRP.