This study aimed to investigate whether neurotransmitter receptors in the nervous system were also expressed in oral keratinocytes. Expressions of various neurotransmitter receptor genes in immortalized mouse oral keratinocyte (IMOK) cells were examined by reverse transcriptase polymerase chain reaction. IMOK cells expressed calcitonin gene-related peptide (CGRP) receptor subunit genes Ramp1 and Ramp3 and glutamate receptor subunit genes Grina , Gria3 , Grin1 , Grin2a , and Grin2d . Moreover, IMOK cells expressed Adrb2 and Chrna5 that encode beta 2 adrenergic receptor and cholinergic receptor nicotinic alpha 5 for sympathetic and parasympathetic neurotransmitters, respectively. The expression of Bdkrb1 and Ptger4 , which encode receptors for bradykinin and prostaglandin E2 involved in inflammatory responses, was also observed at low levels. Expressions of Ramp1 and Grina in the mouse gingival epithelium were also confirmed by immunohistochemistry. When the function of neurotransmitter receptors expressed on IMOK cells was tested by intracellular calcium response, CGRP, glutamate, and cholinergic receptors did not respond to their agonists, but the bradykinin receptor responded to bradykinin. Collectively, oral keratinocytes express several neurotransmitter receptors, suggesting the potential regulation of oral epithelial homeostasis by the nervous system.

Acetylcholinesterase(AChE) is an enzyme which hydrolyses acetylcholine into choline and acetate. Glucose and Adenosine-5'-Triphosphate(ATP) are the primary energy source for the brain and therefore defects in glucose metabolism and the mitochondrial system can affect cognitive function. The fact that the level of acetylcholine(ACh), neurotransmitter, glucose and ATP, are found to be decreased in the brain of Alzheimer patients has lead us to focus on the inhibition of AChE for the developmental research of the Alzheimer's disease(AD) treatment. In this paper we describe the effects of herbal medicine 9908(滌痰化瘀湯加減) in vitro and in vivo. As herb 9908 concentraion increased, the Vmax values of AChE from Electric eel were decreased, which showed that the activity of AChE in vitro was decreased. Also herb 9908 inhibit AChE activity in vivo. When herb 9908 was orally administrated to rats, amount of glucose and ATP which are energy source in metabolism, increase in brain and blood of rats. These result are also interesting in their effects for AD treatment compare with comercial drugs such as Cognex and Aricept. Furthermore, when considering the toxic problems of the Cognex and the Aricept, these oriental medicines could be very valuable medicine for treatment of AD. Abbreviation AD: Alzhemer's disease, AChE: acetylcholinesterase, ACh: acetylcholine, ATCh: acetylthiocholine, DTNB: 5,5‘-dithio-bis-2-nitrobenzoate, ATP: Adenosine-5'-triphosphate GAPD: Glyceraldehydephosphate dehydrogenase PGK : phosphoglycerate phosphokinase