IMED3001 Midterm: IMED3001_ Tubuloglomerular feedback

85 views2 pages

Document Summary

A collection of densely packed epithelial cells at the tal/dct junction. Juxtaposed to its own glomerulus, between the afferent and efferent arterioles. Position enables it to rapidly alter glomerular resistance in response to changes in the flow rate through the distal nephron. Md monitors tubular fluid composition (an indicator of gfr). Dct[nacl] time spent in tubules elevated gfr. Md nacl sensor: na-k-2cl cotransporter (nkcc2). Decreased nacl stimulates the release of adenosine & no from the macula densa aff. art. dilation gfr. Dct [nacl]aff. art dilation gfr. Dct [nacl] aff. art. constriction gfr. Moderate - aff. /eff. art. rbf/gfr urine bvol/bp. Normally minimal activity; overrides if strong eg. after haemorrhage renal shut-down . (limits rbf but maintains" gfr due to greater efferent constriction) (*but massively increases bp at the same time perfusion pressure* = it depends, sorry) Intraglomerular mesangial cells (smooth muscle-ish) regulate intraglomerular capillary blood flow.