UNASSIGNED: Ageing has a profound effect upon gastrointestinal function through mechanisms that are poorly understood. Here we investigated the effect of age upon gastrointestinal sensory signalling pathways in order to address the mechanisms underlying these changes. In-vitro @entity19 @entity694 with attached splanchnic and mesenteric nerves were used to study mechanosensory and chemosensory afferent function in 3, 12 and 24  month old C57BL/6 animals. Quantitative RT-PCR was used to investigate mRNA expression in colonic tissue and dorsal root ganglion (DRG) cells isolated from 3 and 24  month animals, and immunohistochemistry was used to quantify the number of 5-HT expressing EC cells. Colonic and jejunal afferent mechanosensory function were attenuated with age and these effects appeared earlier in the colon compared to the jejunum. Colonic age-related loss of mechanosensory function was more pronounced in high threshold afferents compared to low threshold afferents. Chemosensory function was attenuated in the 24  month colon affecting @entity4412 and serotonergic signalling pathways. High threshold mechanosensory afferent fibres and small diameter DRG neurons possessed lower functional @entity4412 receptor responses, which occurred without a change in @entity4412 mRNA expression. Serotonergic signalling was attenuated at 24  months, but @entity15140 and @entity15141 mRNA expression was elevated in colonic tissue. In conclusion, we saw an age-associated decrease in afferent mechanosensitivity in the @entity19 colon affecting HT units. These units have the capacity to sensitise in response to injurious events, and their loss in ageing may predispose the elderly to lower awareness of @entity66 . This article is protected by copyright. All rights reserved.

Ageing and gastrointestinal sensory function: Altered colonic mechanosensory and chemosensory function in the aged XXXX .

@entity66 :: ('MESH:D004194', 'Disease') :: ['GI injury or disease'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity4412 :: ('193034(Tax:10090)', 'Gene') :: ['TRPV1'] @entity694 :: ('MESH:D003110', 'Disease') :: ['colonic and jejunal preparations'] @entity15141 :: ('216343(Tax:10090)', 'Gene') :: ['TPH2'] @entity15140 :: ('21990(Tax:10090)', 'Gene') :: ['TPH1']
@entity19 :: (10090,Species) :: ['mouse']
