Formaldehyde up-regulates TRPV1 through MAPK and PI3K signaling pathways in a rat model of bone cancer pain

Abstract

Formaldehyde at a very low concentration up-regulates TRPV1 expression through mitogen-activated protein kinase and PI3K, but not PKC, signaling pathways. These results further support our previous finding that TRPV1 in peripheral afferents plays a role in bone cancer pain.

Modulation of Nav1.8 by Lysophosphatidic Acid in the Induction of Bone Cancer Pain

“…As in our previous studies [19,20,37], the hindpaw withdrawal threshold (PWT) was determined by a calibrated series of von Frey hairs (1,2,4,6,8,10,15, and 26 g; Stoelting, Wood Dale, IL), applied in ascending order for 3 s to the center of the plantar surface of the left hindpaw. A positive response was considered only when the hindpaw was completely lifted off the platform.…”

“…Various cancer cells release algogenic substances such as tumor necrosis factor, bradykinin, nerve growth factor (NGF), and formaldehyde that may sensitize primary afferent neurons or destroy peripheral nerve fibers [4][5][6][7][8].…”

Formaldehyde increases intracellular calcium concentration in primary cultured hippocampal neurons partly through NMDA receptors and T-type calcium channels

“…Neurosci Bull December 1, 2012, 28(6): 715-722 716 We found that formaldehyde concentration is elevated in the spinal cord of rats with chronic pain [6] . Formaldehyde derived from local metastasized tumor tissues excites peripheral nociceptive neurons and thus can induce cancer pain [7] .…”

Recent progress in understanding the mechanisms of pain and itch

“…Ten laboratories from China and the USA have contributed 11 papers to this special issue: 5 reviews and 6 full research articles [5][6][7][8][9][10][11][12][13][14][15] . This special issue aims to cover several areas of research in pain and itch, from peripheral to central mechanisms, and also from neuronal to glial mechanisms.…”

“…First, Dong et [9] . Second, Han and colleagues show that TRPV1 expression in DRG neurons is up-regulated after exposure to formaldehyde and in the context of bone cancer pain [10] . Third, Ding et al reveal that a TRPC channel antagonist can alleviate inflammatory pain [11] .…”