Gender- and Age-Related Differences in Muscular and Nerve-Mediated Responses in Human Colon
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : M. A. Maselli P. Trisolini I. Demma F. Pezzolla F. De Ponti
- چاپ و سال / کشور: 2010
Description
Background Gender- and age-related differences in muscular and nerve-mediated responses in human colon are poorly characterized. We studied carbachol-induced motor responses and electrically evoked contractions in sigmoid circular muscle from adult and elderly patients of different gender. Methods Sigmoid colon segments were obtained from 24 men and 16 women undergoing left hemicolectomy for colon cancer. Isometric tension was measured on muscle strips exposed to increasing carbachol concentrations. The effects of atropine, guanethidine, L-nitro arginine methyl ester (L-NAME), and tetrodotoxin on electrically evoked contractions were also studied. Results Female patients showed higher maximal response to carbachol than male patients, elderly females being the most sensitive to carbachol among all patient groups. Electrically evoked contractions were linearly related to stimulation frequency and abolished by tetrodotoxin. Electrically evoked contractions were significantly more pronounced in elderly male patients; they were reduced by atropine and guanethidine and increased by L-nitro arginine methyl ester in the presence of atropine and guanethidine (P\0.05). The effect of L-NAME was most marked in elderly male patients and least pronounced in elderly females. Conclusions The response to carbachol and the role of nitrergic pathways differ according to age and gender; this may depend on muscarinic receptor upregulation or humoral factors affecting nitric oxide release, respectively.
Dig Dis Sci (2011) 56:352–358 DOI 10.1007/s10620-010-1324-0 Received: 20 January 2010 / Accepted: 17 June 2010 / Published online: 24 July 2010
