SCANNING ELECTRON MICROSCOPY (SEM) OF THE MAMMLIAN URINARY DF)r":li..ICIP'GERTAI,?HAQAC'PXAI 4Tl?j CF T'jC!,ATET) RARhZT 17NA1, CtSlx:X TRACT. Joseph A. Burke, Univ. of Kentucky Col. Wd., Dept. of i;?.*~:~X;hi.:S.~~~;s~l.!h;.Sheslle:r a?d Yert,r?-. :ackt.or-. (~ntr.. hy Ped., Lexington, Kentucky. (Intr. by Nancy H. Holland). K=i+h N. Dri~mreond)?cell surface of the urinary tract at the ultrastructural Zumen membranes isol?t,sd fros r~nalcortex of fetal .3-f; level. We have examined the entire urinary tract of the nor- day,34 week and atiirlt r3hhit.s upre cornparer! for t.reha1as.e mal monkey, and the fusion of podocyte terminal processes in s~ciFir: activity:;~),D-gl itcose ~lptakeand by electron micrn- aminonucleoside-nephrotic rats using SEM. econy(~i*j.i{ri>shborder mrmhranns were im~ati,rejn fetal arld The podocyte has a central perikaryal region that branches 3-5 flay rahhits hut mature in 3J4 week ones by EE.Trehalase,a into radiating processes, which give rise to smaller terminal rli-ncchnrirlase, i % 2 n~n~ke*nnvynle for t.uhula hruyh hor,lem. processes that interdigitate with terminal processes of adja- Tts SA expressed as )unoles/nin/me protein X 10-?,an81 nembrane cent podocytes. In the proximal convoluted tubule the epi- D-glucose untake at 5 m:.! expres.;ed as nmnles/min/me. yrot.ein, thelial cells are covered with elongated closely packed micro- %,or-=. villi. In contrast, stub-like microvilli are seen on the Fetal 3-5 day 34 week Adult cells of the large collecting tubules. Microplications and Trehalasc, SA 1. hr?*.04 6.1727 .R? 65.33i7.46 73.395.6 microvilli are interwoven on the surface of the transitional GI rcose uptake l.??*.Ch ?.58+.17 epithelium of the renal pelvis, the ureters, and the urinary n=h n=6 n* n=6 bladder. These cells are polyhedral in shape, variable in D-~li~coseuptake by membra~eswas exarnined over the range size, and demarcated by distinct cell boundaries. The strati- 0.5 mM-5G rn:.:.Althou~h t.he Kn of clucos? uptake by ~nembranes fied columnar epithelium of the membranous portion of the male from 3-5 day and adults was similar(24 m'l Rr 71 mR),the Vmax urethra is covered with short, stubby microvilli. Partially was lounr.,A nmo!es VS. 31 nmoles.Memhrane glucose uptake was interwoven microplications characterize the surface of the i nhihit,pd by phloridzi n and N-ethyl malemide.Urj ne glucose stratified squamous lining of the female urethra and the dis- fell from .6? mirl in 3 day t.o .n9 mt.1 in 4 week rahbits.These tal male urethra. The podocyte alteration in nephrotic rats studies iqdicate t.hat,:l)trehalasr- SA increases 5nX as brush is seen as a loss of the terminal process interdigitations. horders develop with age,7)elucose transport increases as This study demonstrates that SEM provides data on surface br11::h borders mature.3)Vmax increases as urine glucose dec- topography and ultrastructural morphology that is difficult to reases,4)trehalase is a marker of these changes in the devel- obtain using light and transmission electron microscopy. opment n? cortex luminal m~nli~ranes.

URINARY LDH ISOENZYMES IN THE DIFFERENTIAL DIAGNO- RENAL RESPONSE OF THE FETAL LAMB TO ASPHYXIA - S.S.Daniel, SIS OF KIDNEY AND BLADDER INFECTIONS. Hugo F. M.Yeh,E.T.Bowe,L.S. James,Divisians of Perinatology,College of Carvajal, Richard B. Passey, Michael Berger, Luther Physicians & Surgeons, Columbia University, Babies Hospital, NY, NY. B. Travis, and William B. Lorentz, Univ. of Texas Fetal lambs chronically catheterized & intact in utero, were asphyxi- Med. Br. and Shriner Burns Inst., Depts. of Ped. ated by partial occlusion of the umbilical cord. standard asphyxial and Clin. Path., Galveston, Texas. A Urinary LDH isoenzyme assays were performed in insult was given in 4 experiments by inflating the occluder sufficiently patients with proven kidney (N-15) and bladder (N-15) to lower fetal heart rate 35+5 BPM, raise blood pressure 18+2mmHg, & infections as well as normal controls(N-24). Docu- lower pH by 0.15 units; these chonges were maintained for ihour.This mentation of bladder and kidney infection was accom asphyxial stress caused a marked fall in urine output from a control rate plished by means of the Bladder Washout Test, cul- of 0.17 to 0.03 ml/'kg/min; release of the cord was followed by a diur- ture of ureteric urine(urinary diversion), maximal esis. The fall in urine output was accompanied by a rise in solute con- urine concentration test, clinical symptomatology centration which continued for 1 to 2 hours following the release of the and radiologic appearance of the urinary tract. U-LDH in normal children(10.8~1.0uU/ml) was signi- cord: osmolality rose from 133 to a maximum of 462 mOsm/kg, sadium ficantly lower than in patients with bladder(23.12 from 21.5 to 66.8mEq/L, potassium from 6.8 to 35.8 mEq/l, chloride 4.4uU/ml) , or kidney (231.2t72.2uU/ml) infections from 17.0 to 52.5 mEq/L,urea nitrogen from 35.5 to 125.0 mg%, am- (pc0.05). In the normal population most of the monia from 1.2 to 4.2 mEq/L & titratable acid from 3.4 to 17.4mEdL. enzyme activity was comprised among isoenzymes I Because of the low urine output, there was a fall in salute, electrolyte and I1 (fast zone pattern). In patients with blad- & acid excretion during the occlusion; however, the increase in excre- der infection both fast and slow zone patterns were tion of these components with diuresis during recovery exceeded the observed, but the actual level of isoenzyme V(4k 3.8) was significantly lower than in patients with amount retained during occlusion. These experiments show that while kidney infections(ll6~165)where a slow zone pat- the kidney is capable of contributing to acid elimination, this is accom tern was invariably seen(pc0.05). Since overlap panied by a net loss of water & electrolytes in the urine during recolery occured in only one patient, a correct differential from asphyxia. These observations provide an explanation for the hypo- diagnosis of kidney and bladder infections would natremia seen in infants recovering from severe intrapartum asphyxia. have been possible in 96.6% of the cases.

USE OF 1 ALPHA-HYDROXYVITAMIN D3 ON CHILDREN WITH CHRONIC RENAL RECURRENT HEMOLMIC UREMIC SYNDROME WITH HYPOCOMPLE- FAILURE. James C M Chan, usa an-B Oldham, Michael F Holick & MENTEMIA. Alfred Drukker, Michael Winterborn, Boyce Bennett, Jacob George Washington Univ Children's Hosp Hector F DeLuca. Churg and Ira Greifer (Intr. by Henry L. Barnett), Dept. of Ped. and Nat Med Ctr, Dept of Nephrology; Univ of Southern Calif, Dept of Medicine and Children's Hosp of Los Angeles; Univ Path., Albert Einstein Col. of Med., Bronx, N.Y, of Wisconsin, Dept of Biochemistry, Madison, Wisconsin. The hemolytic uremic syndrome (HUS) usually occurs as a single,acute (Intr by Wellington Hung). episode. Recurrences with intervening periods of complete recavery have It is now well accepted that the kidney activates 25-hydro- rarely been reported. Serum complement levels are stated ta be normal. xyvitamin D to the highly potent metabolite, 1,25-dihydroxy- A girl who developed HUS at the age of 2 years had four recurrences vitamin D3. Impaired activation in uremia may contribute to during the next 23 years. Each time she had micrmngiopathic anemia, renal osteodystrophy. thrombocytopenia and oliguric renal hilure, During recavery from the Recently, we tested the short-term effects of a highly third episode, renal biopsy showed focal and segmental thickening of the potent analog, 1 alpha-hydroxyvitamin D3 (lo(-OH-D3) which is relatively inexpensive to synthesize. Thirty-two mineral glomerular capillary walls due to endothelial edema, mesangial prolifer- balance studies, each comprising a 3 day period, were per- ation and thickening of the lamina interno rara. Between the acute epi- formed before, during and after oral administration of sodes there were no detectable renal or hematological abnormalities. A 1%-OH-D3 (1-4 microgramslday) to four children, aged 11 to transient fall in serum B1C (C3) complement was observed during each of 16 years, with renal osteodystrophy and stable chronic uremia the last three episodes; Clq was depressed during the third, while during (BUN>60mg% and creatinine>5mg%). Serial determinations of the last one, Clq and C4 cs well as components of the alternate pathway iPTH were measured. The results showed that physiological amounts of lo(-OH-D3 stimulated increased absorption of cal- (C3PA and praperdin) were normal. Enquiries to three other clinics re- cium in the gastrointestinal tract and promoted positive vealed that the serum level of C3 was low in 8 of the 17 patients with calcium balances. In addition, serum calcium levels returned HUS in whom it was measured. No correlation with course or outcome to normal and iPTH secretion was suppressed. No complications could be established. We postulate that hypocomplementemia results were encountered. from non-specific consumption of complement during the acute process of These data would infer that lo(-OH-D3 has major therapeutic intmvascular caagulation. However, the possibility that the complement value in the treatment of renal osteodystrophy. system is involved in the pathogenesis of certain forms of HUS cannot be excluded.