Daily expression modulation of SGLT1 in rat jejunum during ontogeny

BASTÓN, JI; CHEDIACK, JG; CID, FD; CAVIEDES-VIDAL E; KARASOV, WH

Boston - USA

Congreso; Annual Meeting of the Society for Integrative and Comparative Biology; 2009

Society for Integrative and Comparative Biology

SGLT1, the small intestine apical membrane protein responsible for active glucose absorption, exhibits a daily pattern of activity and protein and mRNA expression in adult rats. The activity and expression of SGLT1 is higher during dark periods when the rats are active and feeding than during light periods when they rest. However, rats during postnatal growth feed throughout the day and they have increasing nutrient requirements. Thus, we characterized the daily expression modulation of SGLT1 protein in rat jejunum at different ages. Using western blots (WB) we semi-quantified SGLT1 relative to alpha-actin in jejunal homogenates collected at 3:00h, 9:00h, 15:00h and 21:00h from 14d, 21d, 28d and 90d old Sprague-Dawley rats (ad-libitum water and food; light on schedule: 6h-18h). Immuno-reactive bands (with MW compatible with different degrees of glycosylation of the SGLT1 monomer, and the tetramer) for each jejunum sample were summed and normalized to alpha-actin for analyses. SGLT1 expression pattern between ages was: 14d