HEPATOLOGY Vol. 22, No. 4, Pt. 2, 1995 AASLD A B S T R A C T S 505A

1593 IGG AND IGG3 LEVELS OF ANTI-M2 MITOCHONDRIAL AUTOANTIBODIES (AMA) DO NOT PREDICT DISEASE PROGRESSION IN PRIMARY BILIARY CIRRHOSIS (PBC) M. Van Nordstrand r M.E. Gershwin*, M. Malinchoc~ E.R. Dickson~ H.A. H o m ~ Mayo Clinic, Rochester, MN 55905 and *University of California-Davis School of Med, Davis, CA 95616.

Introduction: AMA measured by immunofluorescence (AMA-IF) are useful in the assessment of patients suspected of having PBC. These autoantibodies react primarily with the E2 subunits of pymvate dehydrogenase (PDH-E2) and branched chain ketoacid dehydrogenase (BCKD-E2). We have previously reported that AMA-IF titers do not correlate with disease progression in patients with PBC. In this study, we measured the levels of IgG and IgG3 anti-PDH-E2 and anti-BCKD-E2 autoantibodies using ELISA assays with the recombinant autoantigens PDH- E2 and BCKD-E2, and we tested the relationship between the levels of these autoantibodies and the Mayo Risk Scorn, an independent predictor of disease progression in PBC. Methods: 29 patients previously enrolled in the Mayo d-penicillamine trial (an ineffective therapy) had their sera taken at sequential visits over 2 to 10 years of follow-up. An average of 4.5 sera were available per patient. IgG and IgG3 anti-PDH-E2 and anti-BCKD-E2 autoantibodies were measured quantitatively by calibrated enzyme immunosorbent assays and the results correlated with each patient's Mayo Risk Score and histulogic stage. Results: For each individual patient, over time, the levels of autoantibodies were nearly constant in spite of observed changes in Mayo Risk Score. There was a statistically significant positive correlation (p<0.05) between the mean levels of IgG3 anti-PDH-E2 autoantibodies and disease progression as measured by the Mayo Risk Scores. No correlation was observed between the levels of IgG anti-PDH-E2, IgG anti-BCKD-E2, or IgG3 anti-BCKD-E2 and Mayo Risk Score. The mean titers of autoantibodies did not correlate with histologic stage. Conclusion: The levels of autoantibodies to recombinant mitochondrial antigens remain relatively constant over time in individual patients with PBC. Despite a statistically significant correlation between the levels of IgG3 anti- PDH-E2 autoantibodies and Mayo Risk Scores in this group of patients, we conclude that measurements of these autoantibodies are not useful to predict the rate of disease progression in individual patients with PBC. Further studies are needed to determine if autoantibodies to these mitochondrial antigens are involved in the pathogenesis of PBC.

1594 HAEMODYNAMIC MEASUREMENTS IN THE CIRRHOTIC RAT SHOULD BE PERFORMED IN THE FREELY MOVING RAT. (3. Van Roev. M. Van de Casteele. P. Lijuen. R. VerbesselL J. Fevery. HepatoL, Pharm. and Hypert. Unit, K.U.Leuven, UZ Gas~uisberg, B3000 Leuven, Belgium.

The effect of 5 narcotics on arterial (AP) and portal pressure (PP), heart rate (HR) respiratory rate (RR), plasma nurepinephrine (NE), renie activity (PRA), aldosterone (Aldo), renal plasma flow (RPF) and GFR/RPF was studied in groups of 6 CCI 4 cirrhotic rats. Narcotics used: ether (E), pentobarbital (B), ketamioe (K), diazepam-fluanisune (V) and the freely moving a ~tke rat ( ; hrs following ether (A)). Narcosis A E B ] K AP (nun Hg)*** 107+-19 104+-11 76+29 [ 124+-23 PP(mmHg) 13+-2 10~2 13-+-2 I 11+-4 HR (blmin) 390~30 412-~24 )74±56 I 378+57 RR (b/min) * 98.+-24 71+-8 75+-10 ] 75±13 NE (ng/ml) *** 0.6+1.2 1.5±0.5 ).3±0.0 [ 0.g±0.3 PRA (ng/ml/hr) 35±42 81+-13 52-+-24 52~19 Aldo (pg/ml) 446~239 121±30 65±28 106+2(3 RPF(ml/min/100g) 4.3+-1.3 3.1+-1.5 LI+-I.1 1.9±0.8 GFR/RPF 0.29±0.01 0.39±0.1| .50.z4).lg 0:43-~-0.1 • : p<0.05; ***:p<0.001 In awake rats, the decrease in PP ( 15+- 10%) 5 min. following a 2 ml bleed was more pronounced than the decrease in AP (5+-5%; p<0.0001). This might act as a dcfenee against further bleeding. All narcotics decrease RR and induce a more pronouneed drop in PPand AP following bleeding, compared to A (p=0.02). E does not result in a stable narcosis; B supresses NE and AP; K induces a non-predictable narcosis, leading to or high mortality, or insufficient pain-relief; Diazepam-fluanisune causes profound hypotension with reactive NE release and increase of HR.

Conclusions: The chronically catheterised awake rat provides the model of choice for performance ofhaemodynamic studies in cirrhotic rats.

V 63±12 11+-4

432±-46 77±24 1 A±0.3 81±13

26&+210 1.8±0.8

0.41±0.37

1595 OCTREOTIDE INDUCES A NEGATIVE WATER BALANCE 1N HEALTHY AND CIRRHOTIC RATS DURING A SALT LOAD WITHOUT CHANGING ARTERIAL OR PORTAL PRESSURE. _(3. Van Roev, M. Van de Casteele. F. Nevens. J. Fevery. Dep. of liver and pancreatic diseases, K.U.Leuvan, UZ Gasthuisberg, Leuven, Belgium.

The effect of the somatostatin analogue octrcotide on water and sodium balance and on portal pressure (laP) in cirrhosis remains controversial. We therefore performed a cross-over study in healthy (H) and in CCl4-treated cirrhotic rats without (C) or with ascites (A). Separated by 7 days, urine was collected during a 24 hour salt load (drinking water with NaCl 9g/l), once while administering placebo t.i.d, se. (PI, saline 501d/100g), once during octrcotide (oetreo, 1.5 ~tg/100 g in 50 ~1 saline/100 g) t.i.d, se. An aminopyrine breath-test (APB-tes 0 was performed, and arterial (AP) and PP measured in the freely moving rat

weight evol. (g) *** fluid intake (mYd)** diuresis (mUd) fluid balance (rld)** salt-balance (meq/d) AP (ram Hg) PP (ram Hg) APB-test

H-rat (n=8) PI I octreo

"" 0±3 [ -7+-4 41+-8 1 36.5 23±8 I 24±5 19-±7 [ ! 2±2

1.1±1.711.6±0.6 123±5 127+-11 " 5-+-2 5+0

8.1+2.6

)rior t o (PI) and following octreo. t;-rat In=16) A-rat (n=4)

"' i oetreo PI ] octreo 8+-7 I 2+10 12-~10 ] 1+-4

454-10135+14 41+-16 ] 35±5 22+7 I 17±6 14-~2 [ 16±7 23+-6 118±10 25±11 ] 18--e6

0.5±5.710.4±2.7 ""3.7±1.5 2.7±1.2 111+-101 ! 17±1(3 ""10~121102+11 12±4 I 11+-5 16±1 16±1

L5+3.01 "3.2--1:I.8 **, ***: p<0.Ol and <0.001 resp. for PI vs. octmo; ", "": p<0.05 and <0.01 resp. for difference between the 3 groups (H-, C- and A-rats).

Conclusions: Body weight increased during a salt load in cirrhotic rats with or without ascites, as a result of water and sodium-retention. During octreo water intake was impaired without a change in diuresis, leading to a negative water balance, without change of PP and Na-balanee. Octreotide may thus be useful to correct hyponatremia in cirrhosis.

1596 DIFFERENTIAL GENE EXPRESSION OF THE THREE NATRIU- RETIC PEPTIDES (NP) AND NATRIURETIC PEPTIDE RECEPTOR SUBTYPES (NPR) IN HUMAN LIVER. AM Vollmar, 1G Paumgartner, 1AL Gerbes. Institute of Pharmacology, Toxicology and Pharmacy, Ludwig- Maximilians-University of Munich, Munich, Germany and ~Department of Medicine II, Klinikum GroBhadem, Ludwig-Maximilians-University of Munich, Munich, Germany

Various effects of atrial natriuretic peptide (ANP) on the liver have been observed. However, there is very limited information about the types of receptors for NP being expressed by the human liver. Fur- thermore, the presence of transcripts for the corresponding NP would be of interest. Therefore, aim of the present study was to investigate gene expression of the three NP and NPR in human liver. Methods: Presence of mRNA coding for all three NPR as well as mRNA expression of ANP, brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) was investigated by reverse transcription polymerese chain reaction (RT-PCR). Human liver tissues as well as hepatocellular caminoma tissues were examined. Rat C6-glioma cells transfected with the corresponding human NP-receptor cDNAs served as positive and liver mRNA subjected to PCR without prior reverse transcription as negative controls. Results: Specific PCR-preducts for all three NPR, namely NPR-A, -B as well as -C, could be detected. No major difference in the expression of NP-receptors relative to tubulin mRNA of tumorous and non- tumorous tissue was observed. Moreover expression of ANP and CNP was shown by RT-PCR, whereas mRNA coding for BNP was not de- tectable. The concentration of ANP transcripts was clearly higher (= 2 fold) in hepatocellular carcinoma as compared to non-tumorous liver of the same subjects, even when mRNA levels were corrected for tubulin. Conclusion: Our data demonstrate hepatic NPR transcripts and ANP- and CNP mRNA, thus providing evidence for the existence of a local natriuretic peptide system in the human liver.