Heterogeneous expression of nonmuscle myosin heavy chain-B in mesangial cells of patients with Gitelman's syndrome.
OBJECTIVE
It has been suggested that angiotensin II (Ang II) promotes hypertrophy and hyperplasia of mesangial cells. Nonmuscle myosin heavy chain-B (NMHC-B) and alpha-smooth muscle (SM) actin are considered to be molecular markers for phenotypic change ofproliferative mesangial cells. One of the clinical characteristics in Gitelman's syndrome (GS) is the elevation of plasma Ang II. However, little is known about the relation between Ang II and phenotypic change of mesangial cells in patients with GS. In this report, we examined the expression of NMHC-B and alpha-SM actin in mesangial cells of two GS patients.


METHODS
Plasma renin activity, and the concentrations of Ang II, 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha), urinary kallikrein, and 6-keto-PGF1alpha were measured. Immunohistochemical staining of NMHC-B and alpha-SM actin in mesangial cells of GS patients was also performed.


RESULTS
Both cases of GS showed normal glomerular function, few histological abnormalities, and higher than normal plasma concentrations of renin and Ang II. Furthermore, one case showed a high urinary concentration of kallikrein and the expression of both NMHC-B and alpha-SM actin in mesangial cells. The other case showed a high urinary concentration of 6-keto-PGF1alpha but not kallikrein and without the expression of NMHC-B and alpha-SM actin.


CONCLUSIONS
Not only plasma kinin-kallikrein and prostaglandins, but the renal expression of NMHC-B and alpha-SM actin may be variable in different patients with GS.
Sakumura
T
T
The 2nd Department of Internal Medicine, Yamaguchi University School of Medicine, Ube, Japan.
Umemoto
S
S
Fujii
Z
Z
Fujii
K
K
Kawata
Y
Y
Minami
M
M
Matsuzaki
M
M
D000199:Actins / Q000032:analysis; D000328:Adult; D000450:Aldosterone / Q000097:blood; D000471:Alkalosis / Q000378:metabolism*; D002118:Calcium / Q000652:urine*; D002352:Carrier Proteins / Q000235:genetics; D005260:Female; D005920:Glomerular Mesangium / Q000737:chemistry*; D006801:Humans; D007008:Hypokalemia / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D016234:Kallikrein-Kinin System; D008274:Magnesium / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D018995:Myosin Heavy Chains / Q000032:analysis*; D024501:Nonmuscle Myosin Type IIB; D012083:Renin / Q000097:blood; D049992:Sodium Chloride Symporters; D027981:Symporters; D013577:Syndrome
D000199:Actins; D002352:Carrier Proteins; D049992:Sodium Chloride Symporters; D027981:Symporters; D000450:Aldosterone; D012083:Renin; D024501:Nonmuscle Myosin Type IIB; C103815:nonmuscle myosin type IIB heavy chain; D018995:Myosin Heavy Chains; D008274:Magnesium; D002118:Calcium