AJP - Renal Physiology, Vol 250, Issue 5 790-F797, Copyright © 1986 by American Physiological Society
Dynamic response of PG synthesis to peptide hormones and osmolality in renal tubular cells
R. P. Wuthrich, R. Loup, L. Favre and M. B. Vallotton
A superfusion technique was adapted to collagenase-dispersed renal
medullary and cortical tubular cells to study prostaglandin (PG) synthesis
in response to arginine vasopressin (AVP), angiotensin II (ANG II),
bradykinin (BK), Ca2+ ionophore A23187, and to changes in osmolality.
Medullary and cortical cells promptly responded to the stimuli by an
increase in PGE2 and PGF2 alpha production, whereas 6-keto-PGF1 alpha was
not detected. AVP and BK were active on medullary cells, and ANG II was
active mainly on cortical cells. A23187 stimulated PG synthesis in both
cells but predominantly in the medulla. PG synthesis was dependent on the
presence of extracellular Ca2+. The Ca2+ entry blocking agents verapamil
and lanthanum did not inhibit the PG response to AVP, BK, and ANG II. Thus
peptide hormone-stimulated PG synthesis in renal tubular cells did not
depend on Ca2+ influx through channels blocked by these agents.
Hyperosmolar NaCl or mannitol stimulated PG synthesis in cortical and, more
markedly, in medullary cells. Hyperosmolar urea inhibited PGE2 synthesis
stimulated by peptide hormones, NaCl, and A23187 in both cell preparations.
In conclusion, the superfusion of isolated tubular cells is a useful method
to study the dynamic aspects of renal PG release in response to various
sequentially applied stimuli.
