We have investigated adrenoceptor-mediated responses of muscularis mucosae from the proximal, mid and distal regions of the rat colon. Noradrenaline-induced relaxations of the muscularis mucosae in each region were unaffected by atenolol, butoxamine or propranolol, but they were attenuated by the selective beta3-adrenoceptor antagonist cyanopindolol. The beta3-adrenoceptor agonist CL216343 elicited concentration-dependent relaxation of the muscularis mucosae in all regions of the colon.
View Article and Find Full Text PDFIt is known that the muscularis mucosae and mucosa are not pharmacologically homogeneous throughout the rat colon. The aim of this study was to simultaneously characterize all three neurokinin (NK) receptors in the muscularis mucosae and mucosa along the length of the rat colon. Strips of proximal, mid, and distal colonic muscularis mucosae were prepared for isometric recording or sheets of muscle-free mucosa were mounted in Ussing chambers for measurement of short-circuit current.
View Article and Find Full Text PDFFocusing his analysis on (mostly Athenian) vase paintings of the sixth- and early fifth-century and on a handful of texts from the late fifth- and early fourth-century (again Athenian), Dover depicted the pederastic relationship of erastes (age 20 to 30) and eromenos (age 12-18) as defined by sexual roles, active and passive, respectively. This dichotomy he connected to other sexual and social phenomena, in which the active/ penetrating role was considered proper for a male adult Athenian citizen, while the passive/penetrated role was denigrated, ridiculed, and even punished. Constructing various social and psychological theories, Foucault and Halperin, along with a host of others, have extended his analysis, but at the core has remained the Dover dogma of sexual-role dichotomization.
View Article and Find Full Text PDFWe have used a brief analysis of transport via cystic fibrosis (CF) transmembrane conductance regulators (CFTRs) in various organ systems to highlight the importance of basic membrane transport processes across epithelial cells for first-year medical students in physiology. Because CFTRs are involved in transport both physiologically and pathologically in various systems, we have used this clinical correlation to analyze how a defective gene leading to defective transport proteins can be directly involved in the symptoms of cholera and CF. This article is a "Staying Current" approach to transport via CFTRs including numerous helpful references with further information for a teaching faculty member.
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