Plasma growth hormone and prolactin responses to graded levels of acute exercise and to a lactate infusion

The effect of acute exercise at three graded intensities on plasma growth hormone (GH) and prolactin (PRL) concentrations was examined in three groups of healthy male volunteers. According to their training status these subjects were divided into untrained, moderately trained and highly trained. A clear response of GH to exercise was registered already at an intensity of 50% of maximal oxygen uptake (VO2max) with a maximal response at 70% VO2max and no further effect at 90% VO2max. In contrast, no PRL response was observed at 50% VO2max, a small PRL rise was seen at 70% VO2max and the highest response occurred at 90% VO2max. Basal and exercise-stimulated plasma GH and PRL concentrations were similar in the three groups tested at similar relative workloads, suggesting that physical training induces adaptive changes whereby higher absolute workloads induce similar hormonal and metabolic changes. To examine a potential causative role of lactate in inducing the GH and PRL responses, sodium L-lactate was infused intravenously to normal sedentary volunteers at doses producing plasma lactate concentrations within the range of those seen between 70 and 90% VO2max. This resulted in a significant elevation of plasma GH and PRL concentrations, which, however, were smaller than those obtained at an exercise-induced matched plasma lactate concentration. We conclude that physical training causes adaptive changes in highly trained runners so that identical GH and PRL responses to exercise are recorded at higher absolute workloads. Lactate may be involved in the exercise-induced GH and PRL response; however, it does not appear to play an exclusive role.

Cytokine release and dynamics of leukocyte populations after CD3/TCR monoclonal antibody treatment

Cytokine release and clinical side effects resulting from the use of OKT3 and BMA 031 monoclonal antibodies in the treatment of kidney graft recipients were evaluated and compared. The rise observed in serum levels of interferon gamma. TNF alpha, and IL-8 was similar after administration of either monoclonal antibody. Furthermore, both OKT3 and BMA 031 resulted in rapid disappearance not only of virtually all T cells, but also of substantial percentages of all major leukocyte populations from the circulation; this effect is probably due to cytokine release activating endothelial cells and thereby causing extravasation even of leukocytes not specifically recognized by the administered antibodies. Evidence has thus been obtained that BMA 031 is as potent as OKT3 in inducing unequivocal signs of T cell activation in vivo. However, while OKT3 therapy was accompanied by adverse side effects in our study as in previous ones, we saw no such reactions in any of the patients receiving BMA 031. This contrast might be due to different mechanisms of leukocyte activation possibly inducing other mediators in the case of OKT3, which then, in combination with the cytokines, could generate treatment-associated morbidity.

Increased levels of plasma amylin in advanced renal failure

Amylin, a 37 amino acid polypeptide, has been suggested to play a prominent role in the pathogenesis of insulin resistance in type II diabetes mellitus. Various studies have demonstrated most recently that amylin is cosecreted with insulin. No data are available on the elimination of amylin from the circulation. We therefore tested plasma levels of amylin, insulin and C-peptide in 49 non-obese, non-diabetic patients (27 male/22 female) with various degree of renal impairment (Group A: CCr less than 20 ml/min, n = 20; Group B: CCr 20-89 ml/min, n = 18; and Group C: CCr greater than 80 ml/min, n = 9). We found a significant increase of plasma amylin when kidney function, expressed by creatinine clearance fell below 20 ml/min (17.9 +/- 1.7 vs. 12.2 +/- 0.8 vs. 8.8 +/- 1.2 pg/ml; p = 0.0005). Plasma amylin correlated closely with serum C-peptide (r = .764; p = 0.0001), and to a lesser extent with insulin (r = .595; p = 0.0001) underlining its postulated cosecretion with these peptides. The data indicate that amylin might be eliminated by renal mechanisms. Our data show that besides type II diabetes mellitus, advanced renal failure is another clinical situation with enhanced plasma amylin levels. Whether amylin plays any pathogenetic role in renal patients remains to be elucidated.

Treatment of hyperlipidemic kidney graft recipients with lovastatin: effect on LDL-cholesterol and lipoprotein (a)

An increased incidence of hyperlipidemia places kidney graft recipients at increased risk for cardiovascular disease and may contribute to a decline in graft function. A study was undertaken to evaluate the safety and efficacy of lovastatin in these patients. Twelve kidney graft recipients with stable graft function and a cholesterol (chol) level over 250 mg/dl (6.46 mmol/l) were included. The lipid-lowering treatment consisted of 20 mg lovastatin daily, and all patients received immunosuppression with ciclosporin (CS) and prednisolone. Total chol decreased by 27% (300 +/- 56 to 219 +/- 28 mg/dl; 7.76 +/- 1.45 to 5.66 +/- 0.72 mmol/l; p < 0.01), LDL-chol by 35% (220 +/- 38 to 143 +/- 17 mg/dl; 5.69 +/- 0.98 to 3.70 +/- 0.44 mmol/l; p < 0.01) and triglycerides by 33% (207 +/- 127 to 138 +/- 56 mg/dl; 2.36 +/- 1.44 to 1.57 +/- 0.64 mmol/l; p < 0.05). HDL-chol increased by 10% (57 +/- 11 to 63 +/- 13 mg/dl; 1.47 +/- 0.28 to 1.63 +/- 0.34 mmol/l; NS). The ratio of total chol/HDL-chol, a generally accepted risk predictor of atherosclerosis, fell from 5.4 +/- 1.3 to 3.3 +/- 1.2, p < 0.01. Lipoprotein (a) [lp(a)], an independent risk predictor for atherosclerosis, was also evaluated at baseline and after 6 months of lovastatin treatment and showed a decrease of 39% (32.9 +/- 27.6 to 19.9 +/- 22.9 mg/dl; 0.85 +/- 0.71 to 0.51 +/- 0.59 mmol/l; p < 0.05). No adverse side effects were seen at this dosage, and hepatic and renal parameters remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of recombinant human erythropoietin on anterior pituitary function in patients on chronic hemodialysis

In 7 patients with end stage renal failure, anterior pituitary function was tested by simultaneous application of maximally effective doses of the hypothalamic releasing peptides, corticotropin-releasing hormone, growth hormone-releasing hormone, thyrotropin-releasing hormone and gonadotropin-releasing hormone, and compared to 8 normal controls. In addition to the pituitary hormones, plasma cortisol, thyroxine and testosterone concentrations were measured. To test for possible effects of treatment with recombinant human erythropoietin (rhu-EPO), all patients with chronic renal failure were studied again after partial correction of anemia by treatment with erythropoietin. Before initiation of rhu-EPO treatment, plasma concentrations of follicle-stimulating hormone were significantly elevated and the thyroid-stimulating hormone and prolactin responses to thyrotropin-releasing hormone blunted when compared to normal controls. Treatment with rhu-EPO induced a significant increase in plasma ACTH and follicle-stimulating hormone concentrations. All other pituitary functions remained unchanged. Thus, the general improvement in well-being, working capacity and sexual activity cannot be attributed to hormonal changes.

Influence of HLA phenotypes on the inhibition of in vitro alloreactivity by cyclosporine

Interindividual variations in the immunosuppressive effect of Cyclosporine have been observed in clinical organ transplantation. Searching for an in vitro correlate we investigated a possible relation between inhibition of alloresponsiveness by CsA and the HLA phenotypes of the responder or stimulator in mixed lymphocyte reactions. Peripheral blood mononuclear cells from 28 healthy volunteers were used as responder or stimulator cells (gamma-irradiated) and the inhibitory effect of graded amounts of CsA was determined in 130 criss-cross combinations. Sensitivity of alloresponsiveness to the drug was expressed as the dose causing 50% inhibition (ED50) and was read from the inhibition curves generated after four-parameter logistic curve fitting. ED50 ranged from 0.35 ng/ml to 33.4 ng/ml and correlated only weakly with the magnitude of the response (r = 0.12). In MLC with HLA DR4-positive responder cells, ED50 was significantly lower (Pc = 0.0035, Kruskal Wallis) when compared with MLC with responder cells of other DR haplotypes. For HLA DR5-positive responder cells ED50 was significantly higher (Pc = 0.042) when compared with DR5-negative responder cells. No significant correlation between ED50 and any particular haplotype of the stimulator cells could be observed. Sensitivity to CSA did not differ in MLC with 1 or 2 mismatches in the HLA-DR locus. In summary, we found that sensitivity of in vitro alloreactivity was different for particular HLA DR phenotypes, which may have important implications for the immunosuppressive therapy of transplanted patients with cyclosporine.

[Radiologic therapy of symptomatic lymphoceles following kidney transplantation]

During a four and a half year period ending in November 1988, we performed 13 percutaneous needle aspirations and 35 percutaneous drainages on 32 patients suffering from symptomatic lymphoceles (LC) following renal transplantation. Of 13 needle aspirations, 4 were therapeutic (31%); in 9 cases recurrent lymphoceles were observed within 3 days. 35 percutaneous catheter drainages were carried out on 29 patients. 16 of these (55%) did not require any additional therapy. In 8 cases recurrent lymphoceles were treated surgically by marsupialization, another 5 underwent repeated percutaneous drainage. One patient needed 3 percutaneous interventions until his symptoms ceased. In 8 patients 5 ml. of fibrinous glue was administered before the catheter was removed; nevertheless, 3 of them developed recurrent LC. In the group of patients without any symptoms after percutaneous drainage, 5 LC were infected, in the group of repeatedly drained LC, 2 had superinfection which was treated with antibiotics. All of the infected LC could be managed successfully by percutaneous drainage. The overall rate of success was 72%.

Primary peripheral T cell lymphoma in a kidney transplant under immunosuppression with cyclosporine A

A 56-year-old patient received a cadaveric renal allograft because of primary cystic kidney disease. The donor was a 28-year-old man who died from head trauma. No other major illnesses were present at the time of transplantation. Immunosuppression was performed with cyclosporine A and steroids. After 3 months, the patient presented with fever and abdominal pain which was located in the region of the allograft. Ultrasonography demonstrated a tumor mass at the renal transplant hilus that was suspected to be an infected hematoma. Kidney biopsy from the cortex revealed only severe morphologic signs of cyclosporine A toxicity which was due to high cyclosporine A levels during the first 2 months after transplantation. The patient died from pulmonary embolism 6 months posttransplant. Histologic evaluation of the tumor specimens obtained at autopsy showed an extensive infiltration of the renal hilus and the medulla by a peripheral T cell lymphoma of the large-cell type. The T cell origin was confirmed by immunohistochemistry using the T cell-associated monoclonal antibodies UCHL-1 and MT1.

Metabolic effects of biosynthetic human proinsulin in type 2 diabetes mellitus

Due to a longer plasma half-life and half-time of action on glucose metabolism biosynthetic human proinsulin was thought to be an alternative to long-acting insulin preparations. To test this hypothesis we studied 23 type 2 diabetic patients who could no longer be treated sufficiently with oral hypoglycaemic agents. After an initial 1 week phase during which all patients received protamine bound insulin twice daily, the patients either continued on NPH insulin (Group A, n = 11) or were randomly switched to human proinsulin (Group B, n = 12). Glucose profiles and peripheral and hepatic insulin sensitivity (euglycaemic clamp: 120 mU m-2 min-1) were measured at the end of the initial period (Time 1) and 1 week later (Time 2). The insulin-mediated glucose disposal (RD) was not changed after either treatment (group A: 176 +/- 18 vs. 192 +/- 19 mg m-2 min-1; group B: 175 +/- 15 vs. 174 +/- 12 mg m-2 min-1 for times 1 and 2, respectively, NS). Suppression of hepatic glucose output (HGO) was complete in both groups at both times. Fasting blood glucose levels (FBG) and basal HGO were equally low at times 1 and 2 (group A: FBG 118 vs. 123 mg dl-1, BHGO 81 vs. 79 mg m-2 min-1; group B: FBG 118 vs. 106 mg dl-1, BHGO 87 vs. 84 mg m-2 min-1; NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Secondary hypersplenism due to Caroli syndrome complicating immunosuppression in a renal allograft recipient

The differential diagnosis of thrombocytopenia and leukocytopenia in renal allograft recipient can be troublesome. We report on a patient in whom the rare case of portal hypertension with secondary hypersplenism due to Caroli syndrome was detected to be the cause for the hematological disturbance. The management of the thereby complicated immunosuppressive regimen is discussed.

[Significance of arterial blood pressure for the development of microalbuminuria and retinopathy in type I diabetes mellitus]

The role of hypertension for the combined occurrence of incipient diabetic nephropathy and diabetic retinopathy (RP) was evaluated in 155 insulin-dependent diabetic patients (74 male/81 female); mean age 32.4 +/- 12.2 STD years; means diabetes duration 12.8 +/- 10 STD years). Albumin excretion rate (AER) was measured in 24 hours urine samples by RIA, retinal status was determined by both, fundoscopy and fluorescein angiography. Analysis of the data revealed a statistically significant correlation between the duration of disease and elevated AER (p less than 0.012), and the occurrence of retinopathy (p less than 0.0001). Although there was a close correlation between retinopathy and elevated AER (p less than 0.0001), it is remarkable that 31% of the patients with normal AER (less than 15 micrograms/min) showed signs of non proliferative RP. On the other hand 30% of patients without retinal changes showed an elevated AER (less than 15 micrograms/min). In the group of microalbuminuric patients (greater than 15 micrograms/min) systolic (p less than 0.004) and diastolic (p less than 0.04) blood pressures were significantly higher than in normoalbuminuric patients (less than 15 micrograms/min). Patients with proliferative retinopathy showed significantly higher systolic and diastolic (p less than 0.015) blood pressures compared to patients without retinal changes, though albumin excretion rates were not different in both groups of patients. In conclusion, our results show that diabetic nephropathy and diabetic retinopathy do not develop simultaneously in a representative number of insulin-dependent diabetic patients, but hypertension may be a major risk factor for the development of both microangiopathic complications.

[Retrospective analysis of results and complications following kidney transplantation in diabetic nephropathy--a challenge for the future]

A retrospective analysis was undertaken of the renal transplantation results in diabetic nephropathy over the past 10 years. Out of 428 kidney transplants in 348 patients, 22 transplants were performed in 20 diabetic patients during the observation period. Patient survival for diabetics after 1, 2, and 3 years in contrast to non-diabetic controls was significantly different (70%, 50.9%, 50.9%, respectively versus 93.9%, 89.5%, 83.3% in the non-diabetic control group) (p less than 0.001). Transplant survival was 55%, 42%, 34.4%, versus 74.7%, 67.4%, 57.6% after 1, 2, and 3 years, respectively (p less than 0.08). During the posttransplant period the incidence of cardiovascular and infectious complications, as well as the rate of amputation was much higher than in the pretransplant phase. Main causes of death were cardiovascular or infectious complications. Improvement of the still poor results in diabetic transplant recipients is certainly a challenge for the future.

[Ethylene oxide-induced antibodies and hypersensitivity reactions in hemodialysis]

The presence of antibodies against ethylene oxide, which is used for sterilization of dialyzers, was evaluated in 52 hemodialysis patients (30 male, 22 female). The aim of the prospective study was to evaluate a possible correlation of these antibodies with hypersensitivity reactions during hemodialysis. By means of a radio-allergo-sorbent-test (RAST) only 3.9% (2 patients) were detected to have ethylene oxide antibodies. There was no significant correlation between antibodies on the one hand, and symptoms, eosinophilia and IgE-elevation on the other hand. We could not find ETO-induced hypersensitivity reactions in our study population. Thorough rinsing and sufficient storage time of the dialyzers might be the reasons for these findings.

Cytomegalovirus infection after kidney transplantation using cyclosporin A and low-dose prednisolone immunosuppression

The incidence and clinical relevance of cytomegalovirus (CMV) infection has been investigated in 120 consecutive renal allograft recipients receiving cyclosporin A and low-dose steroid (CsA/LDS) immunosuppression. Forty patients (33.3%) showed serological evidence of recent CMV infection; 21 patients (17%) developed clinically symptomatic infection. A seronegative recipient status and an aggressive additional immunosuppressive therapy were significant risk factors for the development of serological infection. There was, however, no difference with regard to these or any other relevant parameters (HLA matching; pretransplant history) between the symptomatic and asymptomatic group. Furthermore there was no influence of CMV infection, whether symptomatic or not, on graft outcome. During the study CMV infection prophylaxis consisted of single-shot CMV hyperimmunoglobulin in 72 patients immediately before grafting, recombinant interferon alpha 2 in 28 patients, and placebo in 20 patients. There was no beneficial effect of either interferon or hyperimmunoglobulin on the incidence and severity of CMV infection. However, steroid-resistant vascular rejections were much more common in the interferon group. We conclude that the incidence of CMV infection after kidney transplantation using CsA/LDS immunosuppression is lower when compared to kidney grafting with conventional immunosuppression. Prophylactic treatment with single-shot hyperimmunoglobulin is not effective, and recombinant interferon alpha 2 prophylaxis may even exert deleterious effects on graft survival by inducing steroid-resistant vascular rejection.

Variations of susceptibility to alloxan induced diabetes in the rabbit

The variations of susceptibility to alloxan induced Diabetes in a total of seventeen rabbits was described. Our study was designed to explore dosage schedules which might improve rabbit responsiveness to and survival after alloxan treatment. A wide range of response to intravenously administered alloxan was observed. Permanent diabetes (blood glucose 350 mg/dl) was found in three rabbits after a single injection (60 mg/kg in one, 100 mg/kg in two). This effect has persisted for eight months. By contrast, two other rabbits injected with a single dose of alloxan (60 mg/kg) developed only transient hyperglycemia. Similarly, four other rabbits either did not respond or had an incomplete response after receiving a total dose of 120 mg/kg. These data suggest that there is extreme variability in individual rabbits susceptibility to the diabetogenic affects of alloxan.

[Mitral ring calcification in dialysis patients. Echocardiographic diagnosis and etiological factors]

Echocardiography for assessment of presence of mitral ring calcification was performed in 96 dialysis patients. The control group consisted of 1758 consecutive patients without renal disease. For the first time it was shown that dialysis patients with mitral ring calcification (group I) had aortic valve sclerosis, renal osteopathy and peripheral angiopathy more frequently than dialysis patients without mitral ring calcification (group II). There were no significant differences between both groups for calcium, phosphate, calcium-phosphate product, magnesium, parathormone and lipids. There were equal numbers of hypertensive patients in both groups. In comparison to patients without renal disease dialysis patients had calcifications of the mitral ring more frequently (P less than or equal to 0.001) an at an earlier age.