PMID- 9111524
OWN - NLM
STAT- MEDLINE
DCOM- 19970506
LR  - 20200930
IS  - 0037-9727 (Print)
IS  - 0037-9727 (Linking)
VI  - 214
IP  - 4
DP  - 1997 Apr
TI  - Influence of dietary sodium on the renal isoforms of 11 beta-hydroxysteroid 
      dehydrogenase.
PG  - 340-5
AB  - Endogenous glucocorticoids are converted to their biologically inert 
      11-dehydroderivatives by isoforms of the enzyme 11 beta-hydroxysteroid 
      dehydrogenase (11 beta-HSD). The low-K(m), NAD(+)-dependent renal isoform (Type 
      2) identified in the distal nephron protects mineralocorticoid receptors from 
      activation by endogenous glucocorticoids. The function of high-K(m), 
      NADP(+)-dependent renal isoform (Type 1) is less well understood. Since 
      glucocorticoids may modulate sodium transport in renal proximal tubules (PT), we 
      hypothesized that Type 1 activity in this segment may be regulated by dietary 
      Na(+)-11 beta-HSD activity was assessed in homogenates of canine PT by the 
      conversion of cortisol to cortisone in the presence of NADP+ 200 microM. A 
      high-Na+ diet for 4 days increased the Vmax 4-fold, with no change in the Type 1 
      K(m) (40 mEq/day Na+ diet: K(m) 0.959 microM, Vmax 3.40 pmoles/min/mg protein 
      versus 150 mEq/day Na+ diet: K(m) 0.962 microM, Vmax 14.8 pmoles/min/mg protein). 
      Type 1 mRNA also rose in the salt repleted animals. The high-Na+ diet produced no 
      detectable change in the Type 2 isoform enzyme kinetics and mRNA level. No 
      reverse oxo-reductase activity was noted with either renal isoform. Thus, renal 
      Type 1 11 beta-HSD can be regulated by dietary Na+ independent of changes in the 
      renal Type 2 isoform.
FAU - Brem, A S
AU  - Brem AS
AD  - Division of Pediatric Nephrology, Brown University, Providence, Rhode Island 
      0290, USA.
FAU - Bina, R B
AU  - Bina RB
FAU - King, T
AU  - King T
FAU - Chobanian, M C
AU  - Chobanian MC
FAU - Morris, D J
AU  - Morris DJ
LA  - eng
GR  - HL-52972/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Proc Soc Exp Biol Med
JT  - Proceedings of the Society for Experimental Biology and Medicine. Society for 
      Experimental Biology and Medicine (New York, N.Y.)
JID - 7505892
RN  - 0 (Isoenzymes)
RN  - 0 (RNA, Messenger)
RN  - 0 (Sodium Chloride, Dietary)
RN  - 0U46U6E8UK (NAD)
RN  - 53-59-8 (NADP)
RN  - EC 1.1.- (Hydroxysteroid Dehydrogenases)
RN  - EC 1.1.1.146 (11-beta-Hydroxysteroid Dehydrogenases)
SB  - IM
MH  - 11-beta-Hydroxysteroid Dehydrogenases
MH  - Animals
MH  - Dogs
MH  - Female
MH  - Gene Expression Regulation, Enzymologic/drug effects
MH  - Hydroxysteroid Dehydrogenases/genetics/*metabolism
MH  - Isoenzymes/genetics/metabolism
MH  - Kidney Cortex/chemistry/enzymology
MH  - Kidney Tubules, Proximal/drug effects/*enzymology
MH  - Kinetics
MH  - NAD
MH  - NADP/metabolism
MH  - RNA, Messenger/analysis
MH  - Sodium Chloride, Dietary/*pharmacology
EDAT- 1997/04/01 00:00
MHDA- 1997/04/01 00:01
CRDT- 1997/04/01 00:00
PHST- 1997/04/01 00:00 [pubmed]
PHST- 1997/04/01 00:01 [medline]
PHST- 1997/04/01 00:00 [entrez]
AID - 10.3181/00379727-214-44101 [doi]
PST - ppublish
SO  - Proc Soc Exp Biol Med. 1997 Apr;214(4):340-5. doi: 10.3181/00379727-214-44101.