Table 1. Spectrum of biological effects mediated by Ach at airways level.

Target cells	Effects
	Stimulus	Inibition
Epithelial cells	Proliferation
	Mucous secretion
	IL-8 release
	Frequency of ciliary beat
	MAPKs activation
Mucous glands	Secretion
Neutrophils, Magrophages, T lymphocytes	Inflammation	Inflammation
	T cell differentiation	IL-8, TNFa, co-stimulatory molecules inibition
	LT-B4 release
	Chemotaxis
Fibroblasts	Proliferation	Myofibroblasts differentiation Fibronectin release
	IL-8, MMP2 release
	Collagen synthesis
Smooth muscolar cells	Contraction
	Collagen proteins expression
	Mitosis

MAPK, mitogen-activated protein kinase; LT- B4, leukotriene B4; MMP2, matrix metallopeptidase 2 (gelatin A)