Effect of Recombinant Human Prolactin Addition to Biolasol Solution on Biochemical Indicators in Perfundates of Porcine Kidneys

BACKGROUND

The influence of recombinant human prolactin (rh-PRL) added to Biolasol solution (concentration 1 μg/L) on selected markers (pH, osmolarity, Na(I) and K(I) concentration) and enzymatic activity (alanine aminotransferase [ALT], aspartate aminotransferase [AST], and lactate dehydrogenase [LDH]) in perfundates was investigated during flushing and preservation of the isolated porcine kidneys.

METHODS

The pH, osmolarity, concentration of K(I) and Na(I), and enzymatic activity were determined in perfundates collected after the 5th and 30th minutes of perfusion, after 24 hours of organ preservation, and in the 5th and 30th minutes of reperfusion. Kidneys had been flushed and stored in Biolasol (control group) and in Biolasol with rh-PRL (experimental group). Obtained results were compared with Biolasol solution.

RESULTS

In the experimental group, the decrease in pH value in the 5th minute of reperfusion was noted. There was an increase in K(I) concentration, and Na(I) concentration decreased in the 5th and 30th minutes of reperfusion. ALT activity during perfusion and preservation increased, whereas at the 5th and 30th minutes of reperfusion it decreased. AST activity increased during perfusion and preservation and decreased in the 5th and 30th minutes of reperfusion. LDH activity was increased but decreased in the 5th minute of reperfusion.

CONCLUSIONS

Addition of 1 μg/L rh-PRL to Biolasol solution decreases pH and osmolarity values; influences Na(I) and K(I) concentration; increases ALT, AST activity during perfusion and preservation of organs; and decreases ALT, AST activity during reperfusion.

Biolasol: novel perfusion and preservation solution for kidneys

INTRODUCTION

Biolasol solution (Pharmaceutical Research and Production Plant "Biochefa," Sosnowiec, Poland) is a novel extracellular perfusion and ex vivo hypothermic kidney preservation solution. It ensures maintenance of homeostasis, reduces tissue edema, has low viscosity, and allows the graft to preserve structural and functional integrity. It minimizes ischemia-reperfusion damage.

METHODS

Perfundates from control and transplanted kidneys flushed with Biolasol or ViaSpan solutions (Arkas, Warszawa, Poland) were analyzed. Parameters of serum and urine collected from 12 pigs after auto-transplantation were also analyzed. Renal medulla was investigated for structural alterations by analyzing hematoxylin and eosin-stained slides. The mean survival time of pigs after the auto-transplantation procedure was the measure for the novel Biolasol solution effectiveness.

RESULTS

We observed a statistically significant decrease in marker enzyme levels alanine transaminase, aspartate transaminase, lactic dehydrogenase, and ions (Na and K) in pigs with grafts flushed with Biolasol. Histopathologic examination revealed that the renal cortex structure was not damaged after the use of Biolasol solution.

CONCLUSION

Biolasol solution protects kidneys against ischemia damage and does not differ significantly from the "golden standard" ViaSpan solution.

Toll-like receptors 2 and 4 in pigs' kidneys early after autotransplantation procedure

OBJECTIVES

The aim of this paper was to evaluate mRNA expression of Toll-like receptors 2 (TLR2) and 4 (TLR4) and the adaptor protein myeloid differentiation primary-response protein 88 (MyD88) in pigs' kidneys 14 and 30 days after autotransplantation.

METHODS

The research was conducted on 12 animals that underwent left renal transplantation procedure with further standardized rinsing with Biolasol solution and 24 hours' storage in 4°C; subsequently the kidneys were implanted in the right retroperitoneal space after right-side nephrectomy. Six randomly chosen animals (group I) were under observation for 14 days, the other 6 (group II) for 30 days. After these observation periods, the animals were killed and 4-g samples were collected from the renal cortex and medulla.

RESULTS

Expression of mRNA in homogenates of collected samples were determined with the use of reverse-transcription polymerase chain reaction analysis. Obtained results in both groups, presented in relation to GAPDH, were compared with the use of Mann-Whitney U test. Stable graft function was observed in all animals from the 2nd day after the procedure. TLR2 in group I reached the mean value of 3.64 and was statistically significantly higher than in group II (2.19). Inverse proportion was observed in case of mRNA for TLR4: group II presented 2 times higher value than group I (0.25 vs 0.11). Similarly, significant difference was observed in MyD88 (group I, 0.067; group II, 0.45).

CONCLUSIONS

At 14 days after autotransplantation of a pig kidney, mRNA expression for TLR2 is dominant; later, expression increases for TLR4 and MyD88.

Comparison of endothelial nitric oxide synthase and endothelin-1 levels in kidneys removed from living pigs after cardiac arrest and brain death

OBJECTIVES

The aim of this paper was to describe differences between levels of endothelial nitric oxide synthase (NOS-3) and endothelin-1 (ET-1) in swine kidneys removed from living donors (group I) and after inducing brain death by brain herniation (group II) and cardiac arrest (group III).

METHODS

Each group consisted of 3 animals who underwent dual renal removal procedure; kidneys were further rinsed according to standardized procedure with Biolasol perfusion liquid, stored for 24 hours (4°C), and rinsed again. Renal specimens of 4 g mass, including renal cortex and medulla, were collected before and after perfusion (times 0 and 1), after 12 hours (time 2), and after reperfusion (time 3). Enzyme-linked immunosorbent assay was used to describe levels of NOS-3 and ET-1 in collected tissues homogenates. Mann-Whitney U test was used to compare results in groups in relation to total protein content (ng/mg), and the correlation between the 2 substances was measured with the use of Spearman rho.

RESULTS

Group I presented low and stable levels of NOS-3 in all time intervals (averages, 0.73, 0.99, 0.52, and 0.89, respectively). Level sof ET-1 were similar (0.87, 0.63, 0.69, and 0.86, respectively), and significant correlation between levels of the 2 substances was observed. Increased levels of NOS-3 (1.89 and 1.86) and ET-1 (1.38 and 1.49) were observed directly after removal in groups II and III and further maintained during organ storage. No correlation in group I was observed, and after perfusion significantly lower level of NOS-3 was observed in kidneys removed after brain death in relation to group III (1.77 vs 2.60).

CONCLUSIONS

The lowest and stable levels of NOS-3 and ET1 during storage were observed in kidneys removed from living donors. Levels of analyzed substances in this group showed correlation in subsequent time intervals.

The effect of HTK solution modification by addition of thyrotropin and corticotropin on biochemical indices reflecting ischemic damage to porcine kidney

INTRODUCTION

The aim of our study was to evaluate the impact of perfusion with HTK (histidine-tryptophan-ketoglutarate, Custodiol®, Dr. Franz Kohler Chemie, Germany) solution, modified by the addition of porcine thyroid-stimulating hormone (TSH) and corticotropin (ACTH), on selected biochemical parameters of porcine renal damage within 24 and 48 hours after the onset of cold ischemia time.

METHODS

Each study group consisted of 10 adult pigs. During harvesting the kidneys were rinsed with Ringer solution (group 1), HTK (group 2), HTK-TSH (1 μg/dL) or HTK-ACTH (1 μg/dL) in groups 3 and 4. The solutions were cooled to 4°C-6°C. Within 30 minutes of the first perfusion, the discharged fluid was clear and the kidneys cooled to 4°C. The levels of lactate dehydrogenase, asparagine and alanine aminotransferases, lactates, total protein, potassium, calcium, and pH were determined in the perfusate. After 24 and 48 hours the rinsing procedure and the above-mentioned tests were repeated. Differences between the means of 2 independent samples were tested with a nonparametric Mann-Whitney U test.

RESULTS

As the result of hormone addition, in both time intervals it was possible to observe considerably lower protein concentrations (g/L) in perfusates compared with HTK solution, without an addition. At 24 hours, we measured following values: 36 ± 4, 8 ± 3 and 6 ± 1 versus 48 hours, 34 ± 1, 2 ± 1, and 4 ± 1 in groups 2, 3, and 4. A similar pattern was observed with LDH (U/L) at 48 hours: 662 ± 89, 374 ± 151, and 386 ± 111, respectively. Lactate concentrations (mmol/L) were then significantly higher: 1.4 ± 0.3 in the TSH group and 1.2 ± 0.5 in the ACTH group as opposed to 0.2 ± 0.1 in unmodified HTK group.

CONCLUSION

We observed the possibility of cytoprotective actions of TSH and ACTH addition to the perfusion fluid during cold ischemia, positive effects that were especially visible upon prolonged 48-hour storage.

Adrenaline and dopamine in porcine livers after cold preservation with University of Wisconsin histidine-tryptophan-ketoglutarate, prolactin-modified histidine-tryptophan-ketoglutarate solutions

INTRODUCTION

Hepatic ischemia-reperfusion injury remains a significant factor influencing early liver graft function. The aim of this study was to assess the impact on hepatic ischemia as reflected by catecholamine concentrations of different methods of organ preservation.

MATERIALS AND METHODS

Catecholamine levels were measured in 24 (n=6/group) pig livers, which underwent 30-minute warm ischemia followed by 30-minute perfusion and subsequent cold storage for 12 hours. For perfusion and preservation, we used University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK), HTK-modified with prolactin (PRL) or Ringer's solutions. Dopamine (DO) and adrenaline (ADR) concentrations in liver venous effluents were assayed using a radioimmunological method after 30 minutes of perfusion and following 12 hours of preservation.

RESULTS

DO and ADR levels were higher after 12 hours preservation compared to 30 minutes of perfusion. HTK produced an increase of over 100%. Addition of PRL (20 IU/L) did not affect DO and ADR levels after 30 minutes of perfusion, but significantly decreased their concentrations at 12 hours of preservation. After UW perfusion and preservation, we observed a 10% increase in catecholamine levels as compared with postperfusion values. Preservation with Ringer's solution demonstrated significantly higher DO and ADR levels compared with other solutions.

CONCLUSION

Catecholamines are present in the liver after 30 minute of perfusion and 12 hours of cold storage. The increased levels after 12 hours of preservation may be due to their release from intracellular spaces (as a controlled process or as a result of necrosis). It may play a crucial role in reperfusion injury, which, in turn, may explain the mechanism of no-reflow phenomenon.

The effect of HTK solution modification by addition of prolactin on biochemical indices reflecting ischaemic damage to porcine kidney

INTRODUCTION

The aim of our study was to evaluate the impact of perfusion with HTK solution, modified by the addition of prolactin (PRI), on selected biochemical parameters of porcine renal damage within 24 and 48 hours after the onset of cold ischemia time.

METHODS

Each study group consisted of 10 adult pigs. During harvesting the kidneys were rinsed with Ringer's solution (group 1), HTK (group 2), and HTK+PRL in a dose of 0.2 mg/dL, 0.02 mg/dL, and 0.01 mg/dL in groups 3, 4 and 5, respectively. The levels of lactate dehydrogenase, asparagine (AST) and alanine aminotransferases, lactates, total protein, potassium and calcium were determined in the perfusate. After 24 and 48 hours the rinsing procedure and the abovementioned tests were repeated.

RESULTS

After 24 hours of storage, in 4 groups, significantly lower levels of LDH (U/L) were recorded compared with HTK solution alone, namely 235 ± 93 versus 271 ± 125 (perfusion minute, 0), and 55 ± 21 versus 125 ± 94 (30th minute). Similar behavior pattern was presented by AST (U/L) and potassium (mmol/L), and the results were 31 ± 8 versus 35 ± 12 and 16 ± 10 versus 29 ± 14, and 12 ± 3 versus 16 ± 3 and 10 ± 1 versus 13 ± 1, respectively. The changes described above were not observed in the 48th hour of reperfusion.

CONCLUSION

Our study results indicate the possibility of cytoprotective action of PRL after adding it to the fluid perfusing kidneys during cold ischemia. This effect, observed after 24 hours of storage, was to a considerable extent dose dependent. In our experiment the effect was pronounced only at 0.02 mg/dL supply of PRL.

Effect of prolactin on release of selected enzymes from the isolated rabbit liver

This report analyzes the effect of prolactin (PRL) on ALT and AST release from the rabbit liver into the preservation solution. Dissected and perfused livers were stored for 24 hours in Ringer's solution without (control group) or with PRL (experimental group). During the organ preservation, sample of the solution were obtained at 1, 8, 12, 16, 18, and 24 hours. It was found that PRL added to Ringer's solution significantly decreased the quantity and rate of released ALT (P < .081) and AST (P < .029) from the preserved liver. ALT was released 2.51 times more slowly (kappa = -0.03329 [h(-1)]) and AST 3.43 times more slowly (kappa = -0.08356 [h(-1)]) into Ringer's solution with PRL. The experimental group showed maintenance of the value of the de Ritis index at a stable level between 2.0-3.0. In conclusion, PRL added to a preservation solution significantly decreased the quantity and slowed the release rate of ALT and AST aminotransferases from the preserved rabbit liver, implying that this hormone has hepatoprotective properties.

The kinetic study of the selenium yeast stability

The kinetics of degradation of selenium yeast was investigated at different temperatures. The effect of temperature has been determined and from this data, applying of Arrhenius-law, the stability of selenium yeast at 25 degrees C has been predicted and the t10 was determined. The changes in selenium content of the selenium yeast were determined by the fluorimetric method. It was proved, that the decomposition observed the first-order kinetic equations. The shelf life of selenium yeast predicted from the Arrhenius plot exceeded 1126 days. In the other hand the stability of selenium preparation in normal storage conditions (T = 25 degrees C) was determined to compare with predicted values. These results were found in agreement with experimental ones obtained at room temperature. No discernible physical changes of selenium preparations were observed after the storage in normal conditions (25 degrees C).

Distribution of 125J-labeled leucopyrokinin (LPK) in rats

The distribution in parts of the brain and internal organs of 125J-labeled leucopyrokinin (LPK), an insect myotropic peptide injected into the lateral brain ventricle was determined in rats. A high accumulation of this peptide in adrenals and in the hypothalamus and hippocampus of the brain was found. A lesser but significant LPK accumulation in other internal organs and parts of the brain was also observed. The significance of this effect for the biological activity of LPK in rats is discussed.

Pulsatile and moderated release of dalareline from Zn(II) complexes in the form of suspension

The influence of molar relation of the Zn(II)-Dalareline upon the speed and character of peptide release from these complexes was defined. Sparingly soluble complexes were obtained in the form of suspension to be applied palanterally. The dynamics of peptide release was observed in vitro conditions. The results obtained show that dalareline is released from all the complexes in the pulsatile way. 5 to 7 significant peaks of the released peptide were observed. It was stated that the molar relation of Zn(II)-Dalareline in the range of 0.5:1 do 100:1 ensures pulsatile character of peptide release from all the complexes. Depending upon this relation dalareline release is differentiated, and the peaks occur in different times. The number of peaks in this case is not connected with the molar relation of Zn(II)-Dalareline. However, it is significantly connected with the amplitude and the size of peaks of the released peptide. The time of half-release of dalareline was 3.12 h to 26.45 h and it was stated that it is significantly dependent upon the molar relation of Zn(II)-Dalareline. The greater the molar relation of the Zn(II)-Dalareline, the longer the time of the peptide release from this complex (r = 0.518).

Distribution of prolactin in selected rat organs and tissues

A single dose of 25 microg prolactin (PRL)/kg of rat body weight was administered to rats subcutaneously. At 1, 2, 3, 4 and 5 h after the injection, selected organs and tissues were taken for analysis. It was found that 1 h after administration, the highest amount of PRL accumulated in the milk (lactiferous) gland, the blood, the ovaries, the pituitary and the liver. Over time, the prolactin content in the selected organs and tissues decreased. PRL is selectively captured by the milk gland, the pituitary, the ovaries, the liver and the heart. Based on the value of the organ or tissue capacity index for PRL, the following order was established for the organs and tissues to which the hormone binds: milk gland > blood > pituitary > ovaries > lungs > liver > cranial bone > spleen > heart > kidneys > muscular tissue > adrenals > adipose tissue > brain.

The influence of physicochemical properties of amino acid on their release from the Zn(II)-amino acid complexes in suspension

The release processes of selected amino acids, for the parenteral administration, from the Zn(II)-Amino acid complexes in suspension were investigated in vitro. The Zn(II)-Amino acid complex dissociated and Zn(II) ions and amino acid were released. Tyrosin, possessing the highest affinity vs. the Zn(II) was released from the complexes in a continuous (monotonous) manner. Histidine, cysteine and alanine were released in a pulsating manner. The molar ratio Zn(II)-Amino acid determined the release rate and the manner of pulsating or continuous release of amino acids studied. The lower the molar ratio Zn(II)-Amino acid was, the longer was the amino acid release time form the complex. Molecular weight of the amino acids and their affinity vs. Zn(II) considerably influenced the continuous release rate from the complex. The higher the molecular weight of an amino acid, the lower was its extent of the release from the complex. The amino acids possessing higher affinity vs. Zn(II) were more slowly released too. The slowest release was observed for tyrosine which possessed the aromatic chemical structure, and the quickest release was in the case of the aliphatic amino acid--alanine. The obtained complexes were characterised by the moderated release of the amino acids in vitro.

The properties of solid Zn(II)-amino acid complexes in the form of suspensions

An investigation was made into the experimental conditions for the formation of poorly soluble complexes of the divalent Zinc(II) combined with the following selected amino acids: tyrosine, tryptophan, cysteine, histidine, and alanine, in the form of suspensions for parenteral administration. The number of Zn(II)-binding sites in the amino acid (n) as well as the amino acid affinity to Zn(II) (Ka), were determined. Cysteine was found to have the highest number of Zn(II)-binding sites--3, whereas alanine the lowest--1. In the conditions described herein, Zn(II) amino acid complexes of diverse stability (durability) were obtained. The analysis of the kinetics of the binding revealed that the most stable complexes were those formed by Zn(II) in combination with tryptophan (Ka = 405.78 microM(-1) +/- 12.17), and with tyrosine (Ka = 343.88 microM +/- 22.35); whereas the least stable complexes were those formed by Zn(II) in combination with histidine (Ka = 29.90 microM +/- 4.78), and with alanine (Ka = 13.0 microM(-1) +/- 1.04). Cysteine formed complexes of intermediate stability (Ka = 168.53 microM(-1) +/- 12.36). The stability ofthe Zn(II) amino acid complexes obtained was conditioned by both the molecular weight (P = 0.033) of the amino acid and its isoelectric point (P < 0.001).

Uptake of prolactin and tyroliberin by the heart

The aim of this study was to observe the specificity of prolactin and tyroliberin uptake and thus to determine their affinity for the heart ventricles and atria. Comparison of the uptake of the examined substances revealed that more of these hormones reached the atria than the ventricles. The contents of prolactin and tyroliberin in the atria were statistically significant compared with 125J. The results observed provide evidence for nonuniform prolactin uptake by the heart.

Bioavailability of dalarelin--a superactive GnRH analogue--in rats

125I-marked dalarelin (a modified analogue of GnRH) or GnRH (gonadotropin-releasing hormone) were administered to the tested rats in single doses of 127 ng/kg by subcutaneous injections. Dalarelin and GnRH were absorbed from the injected doses in 0.64 and 0.49%, respectively. Only one remarkable maximal concentration of these hormones was noticed in rats' blood 30 min after the administration. Dalarelin maximal concentration was 261.5 pg/cm3 and was 93.43% higher than the maximal concentration of GnRH. Dalarelin bioavailability was 1651.89 pg/cm3, whereas GnRH bioavailability was 718 pg/cm3 h. The bioavailability level of dalarelin was 230% compared with that for GnRH, which was accepted as a pattern of bioavailability.

Pharmacokinetics of ferrous fumarate in rats

There have been evaluated changes of iron concentration in serum dynamics after single oral administration of ferrous fumarate to rats. Pharmacokinetics parameters were determined and the results were compared to those ferric gluconate.

Bioavailability of buserelin and gonadorelin in suspensions

There have been determined parameters defining biological availability of gonadorelin and buserelin marked 125 J. Hormonal preparations were hypodermically administered to the rats in suspensions containing zinc ions of the molar ratio of the hormone: zinc 1:5. It has been stated that buserelin in suspension is better available to an organism than gonadorelin .

Biological accessibility of calcitonin and osteocalcin marked 125J for rats

Biological accessibility of calcitonin and osteocalcin marked 125J for rast. In this study we estimated the biological accessibility and the degree of biological accessibility of calcitonin in relation to highly specific marker-osteocalcin after a single intraperitoneal administration. We showed mean values of biopharmaceutical parameters for the analysed hormones.

Preparation and properties of buserelin suspensions

Obtaining and some properties of suspensions with buserelin-there were obtained buserelin suspensions with zinc ions with pH 7.2-7.5 and hormone: zinc molar ratio from 1:2.5 to 1:500. The obtained buserelin suspensions show moderated hormone release in vitro and prolonged action in vivo. The pulsating buserelin release from suspensions has been found in vitro and in vivo.

Pharmacokinetics and distribution of selenium in blood and organs of rats

The dynamics of selenium concentration changes in blood, organs and tissues of rats after a single intragastric administration of selenium yeast and sodium selenite was determined. The course of selenium concentration changes in blood was described, the pharmacokinetic parameters were estimated according to the trivalent equation of dicompartment model and the selenium content in liver, kidneys, small intestine, spleen, heart, brain, stomach, testicles and prostate was determined 48 h after the administration of selenium preparations.

[Isolation of prolactin from lyophilized porcine pituitary glands]

The optimal conditions for lyophilization of porcine pituitary glands and isolation of pure prolactin from lyophilized preparation have been investigated. The isolation method consisted in the extraction of crude pituitary preparation with acidified acetone followed by precipitation of crude prolactin preparation (acid acetone powder) by increasing the concentration of acetone in the extract to 92%. Further purification of prolactin was achieved by fractional precipitation at varying pH values and gel filtration on Sephadex G-75 column in a pH 7.5 phosphate buffer. This final procedure resulted in obtaining the monomeric form of prolactin. The identity of the isolated hormone was confirmed by spectrophotometric and radioimmunological methods as well as by polyacrylamide gel electrophoresis.