RENAL PROSTAGLANDIN E₂ SYNTHESIS (PG SYN) AND DEGRADATION (PG DEG) IN THE DEVELOPING RAT

Abstract

Postnatal development of GFR and RBF is associated with a fall in renal vascular resistance that may be mediated by vasoactive substances. We examined differences in the regulation of one such substance, PGE₂. The present studies examined renal cortical (C) and medullary (M) PG syn and PG deg in neonatal rats (N) aged 17 days (30.7g), young rats (Y) 33 days (101g), and adult rats (A) 120 days (413g). PGE₂ syn from ¹⁴C-arachidonic acid was determined in C and M microsomes by thin layer chromatography (TLC). PGE₂ degradation was determined by following the disappearance of ³H-PGE₂ substrate in cytosolic fractions of C and M by TLC. Mean values (±1SE) for PG syn (% arachidonate conversion)and PG deg (% PGE₂ disappearance) are shown below: ^* = p<0.05, N vs Y; † = p<0.05, Y vs A; ψ = p<0.05, A vs N; (n) = number of animals.

PG syn in C microsomes is highest in N rats and decreases with age; in contrast M PG syn is lowest in N rats and increases with age. Both C and M PG deg are highest in N rats and decrease with age. These studies demonstrate for the first time that significant age dependent differences in regional PG syn and deg exist in the developing rat kidney. The elevated synthesis of vasodilating PG's in the cortex may play a causal role in the increases in renal perfusion and glomerular filtration typical of the developing kidney.

Log in or create a free account to read this content

Gain free access to this article, as well as selected content from this journal and more on nature.com

Access through your institution

or

Sign in or create an account

Continue with Google

Continue with ORCiD