Gene expression of histamine H1 receptor in guinea pig primary sensory neurons: a relationship between H1 receptor mRNA-expressing neurons and peptidergic neurons.

摘要: Abstract Pharmacological studies have suggested that a subgroup of primary sensory neurons is responsive to histamine via the H1 receptor. We addressed this issue using in situ hybridization histochemistry with cRNA probe for guinea pig receptor gene. About 15% trigeminal and lumber dorsal root ganglion (DRG) neurons, but none nodose were intensely labeled probe. The mRNA-positive exclusively small size, demonstrated give rise unmyelinated fibers by ultrastructural analysis isolectin B4-labeling. However, mRNA-expressing DRG not immunoreactive substance P (SP) calcitonin gene-related peptide (CGRP). A marked increase number observed 1–5 days after crush injury sciatic nerve (3–4-fold control value). These turned also mainly small-sized. mRNA signals detected many peptidergic (SP/CGRP) contrast normal state. On other hand, which showed intense labeling condition, down-regulated. results suggest include two kinds receptor-expressing one expressing mRNAs state up-regulating following peripheral damage.