“…Recently, sensitive in situ hybridization and RNase protection analyses have unveiled widespread expression of trkA in many non-neuronal tissues, including kidney, thymus, testes, stomach and muscle (Lomen-Hoerth and Shooter, 1995;Wheeler et al, 1998). It has also been shown that NGF-triggered trkA signaling is involved in many autocrine and paracrine circuits playing important roles in the growth, survival and/or di erentiation of di erent cell types, including mast cells and B memory cells (Tam et al, 1997;Torcia et al, 1996; skin melanocytes (Yaar et al, 1994); and cells from the ovary (Mayerhofer et al, 1996); prostate (Dalal et al, 1997); and pancreas (Miralles et al, 1998). Loss of trkA function is responsible for a human disease, congenital insensitivity to pain with anhidrosis (CIPA), characterized by lack of reaction to noxious stimuli (Indo et al, 1996).…”