Transepithelial D-glucose and D-fructose transport across the American lobster, Homarus americanus, intestine.
نویسندگان
چکیده
Transepithelial transport of dietary D-glucose and d-fructose was examined in the lobster Homarus americanus intestine using D-[(3)H]glucose and D-[(3)H]fructose. Lobster intestines were mounted in a perfusion chamber to determine transepithelial mucosal to serosal (MS) and serosal to mucosal (SM) transport mechanisms of glucose and fructose. Both MS glucose and fructose transport, as functions of luminal sugar concentration, increased in a hyperbolic manner, suggesting the presence of mucosal transport proteins. Phloridizin inhibited the MS flux of glucose, but not that of fructose, suggesting the presence of a sodium-dependent (SGLT1)-like glucose co-transporter. Immunohistochemical analysis, using a goat anti-rabbit GLUT5 polyclonal antibody, revealed the localization of a brush border GLUT5-like fructose transport protein. MS fructose transport was decreased in the presence of mucosal phloretin in warm spring/summer animals, but the same effect was not observed in cold autumn/winter animals, suggesting a seasonal regulation of sugar transporters. Mucosal phloretin had no effect on MS glucose transport. Both SM glucose and SM fructose transport were decreased in the presence of increasing concentrations of serosal phloretin, providing evidence for the presence of a shared serosal GLUT2 transport protein for the two sugars. The transport of d-glucose and d-fructose across lobster intestine is similar to sugar uptake in mammalian intestine, suggesting evolutionarily conserved absorption processes for these solutes.
منابع مشابه
Comparative cation dependency of sugar transport by crustacean hepatopancreas and intestine
Glucose is transported in crustacean hepatopancreas and intestine by Na(+)-dependent co-transport, while Na(+)-dependent D-fructose influx has only been described for the hepatopancreas. It is still unclear if the two sugars are independently transported by two distinct cation-dependent co-transporter carrier systems. In this study, lobster (Homarus americanus) hepatopancreas brush border membr...
متن کاملIdentification of a novel sodium-dependent fructose transport activity in the hepatopancreas of the Atlantic lobster Homarus americanus.
[(3)H]Fructose and [(3)H]glucose transport were determined in brush-border membrane vesicles (BBMV), basolateral membrane vesicles (BLMV) and isolated cells (E, R, F, B) of H. americanus (Atlantic lobster) hepatopancreas. Glucose transport in BBMV was equilibrative in the absence of sodium and concentrative in the presence of sodium. Sodium-dependent glucose transport by BBMV was not inhibited ...
متن کاملCharacterization of ion transport in the isolated epipodite of the lobster Homarus americanus.
Unfolded epipodite isolated from American lobsters (Homarus americanus) acclimated to dilute seawater was mounted in an Ussing-type chamber for ion transport studies. The split epipodite is an electrically polarized, one-cell-layer epithelium supported with cuticle. Under open-circuit conditions, the transepithelial potential was -4.2+/-1.0 mV (N=38). In the short-circuited epithelium, the curr...
متن کاملEpithelial glucose transport by lobster antennal gland
Transport of d-[3H]glucose into lobster (Homarus americanus) brush-border membrane vesicles (BBMVs) prepared by Mg2+ precipitation from antennal gland labyrinth-coelomosac tissue was examined. Influx of d-glucose occurred primarily by a phlorizin-sensitive, Na+-dependent carrier similar to that found in vertebrate renal epithelium. An inwardly directed Na+ gradient drove concentrative d-glucose...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of experimental biology
دوره 214 Pt 14 شماره
صفحات -
تاریخ انتشار 2011