Extrathoracic negative pressure ameliorates lung injury during mechanical ventilation in experimental pigs.

Mechanical ventilation (MV) is a supportive and life-saving therapy, however, it can cause ventilator-induced lung injury as a common complication. Thus, recruitment manoeuvres (RM) are applied to open the collapsed alveoli to ensure sufficient alveolar surface area for gas exchange. In the light of the fact that positive pressure ventilation is currently the standard treat- ment for improving pulmonary function, extrathoracic negative pressure is considered as an alter- native form of respiratory support. The aim of this study was to estimate the proinflammatory and oxidative response during MV and lung injury as well as the response after RM. All studied parameters were assessed at the following time points: T1-spontaneous breathing, T2- MV, T3- lung injury, T4 -RM. During MV (T2) elastase, MPO, ALP release, nitrite and superoxide generation significantly increased, whereas in later measurements a decrease in these values was noted. The MDA plasma concentration significantly (p⟨0.05) increased at T2, reaching a level of 13.30±0.87 nmol/ml; at other time points the values obtained were similar to the baseline value of 9.94±0.94 nmol/ml, whereas a gradual decrease in SOD activity at time T2-T4 points in comparison with the baseline value was found. During the study both neutrophil activity and oxi- dative stress indicate exacerbated response after MV and lung injury by bronchoalveolar lavage; however, extrathoracic negative pressure system as the MR ameliorates damaging changes which could further lead to serious lung injury.

Transport induced inflammatory responses in horses.

Deleterious response to road transport is an important problem in equine practice. It determines different physiological, immunological and metabolic changes which lead to increased susceptibility to several disorders such as pneumonia, diarrhea, colics, laminitis, injuries and rhabdomyolisis. The aim of our study was to look for possible relationships between transportation of female young and older horses over a long and short distance and an inflammatory state reflected by an increase of acute phase protein concentration, oxidative stress and muscle injury. The study was conducted on 24 cold-blooded female horses divided into four groups. Six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 550 km, six fillies aged 6-18 months and six mares aged 10-12 years were transported over the distance of about 50 km. Plasma and serum were obtained from blood samples taken before transportation (T0), immediately after transportation (T1) and at an abattoir during slaughter (T2). In these samples fibrinogen, MDA, AST and CK were assessed. Fibrinogen increased in all studied groups especially in fillies after long distance transportation, where it reached 205±7.07 mg/dl before transportation, 625±35.35 mg/dl after transportation, and 790±14.14 mg/dl during slaughter. MDA concentrations rose after transportation and reached the maximal level during slaughter. CK activity was more elevated after short transportation in younger horses, whereas initial activity of AST was higher in older horses. We estimated that intensified responses from acute phase, oxidative stress and muscle injury parameters indicated an inflammatory state.

Fibrogenic response of hepatic stellate cells in ovariectomised rats exposed to ketogenic diet.

The discrepancy about the role of estrogens in hepatic fibrogenesis and lack of studies addressed of ketogenic diet (KD) on hepatic stellate cells (HSC), prompted us to investigate the activity of HSC in control, KD- and thioacetamide (TAA)-administrated rats with different plasma concentration of estradiol (E2). HSC were isolated by the collagenase perfusion methods and separated by the Percoll gradient centrifugation. After the 4(th) and 8(th) day of incubation, lysates of HSC and the media were collected for further analysis. The HSC derived from KD-rats released remarkably more transforming growth factor (TGF)-ß1 than cells obtained from animals fed with a standard diet. The ovariectomy of KD-rats markedly intensified the secretion of this fibrogenic cytokine on the 8(th) day of incubation (201.33 ±1 7.15 pg/ml). In HSC of rats exposed to E2, the TGF-ß1 concentration did not exceed 157 ± 34.39 pg/ml. In respect to the collagen type I, the HSC obtained from ovariectomised KD-rats released an augmented amount of this ECM protein after the 8(th) day of culture (1.83 ± 0.14 U/ml). In the same time, higher quantities of ASMA appeared in the KD rats (1.41 ± 0.3 pg/mg protein). Exposition of rats to E2 did not markedly decrease the amount of ASMA. In summary, KD was able to induce morphological and functional changes in HSC, especially derived from rats deprived of ovarian estrogens. However, the preservation of E2 in ovariectomised rats didn't substantially alter the activation of HSC.

Proliferation, differentiation and apoptosis of choline deficient ethionine supplemented diet-rat oval cells under the influence of 2-methoxyestradiol.

Since numerous studies indicate that 2-methoxyestradiol (2-ME) as a metabolite of 17beta estradiol (17ß-E(2)) may exert antitumor activity by unclear mechanism, we undertake the study to elucidate the effect of 2-ME on oval cells (OC) activated by a carcinogenic choline deficient ethionine supplemented diet (CDE diet). Isolated OC were treated with different concentrations of 2-ME for 24, 48 and 72 hours. In these periods of time phenotypic studies, apoptosis detection and proliferative activity of cells were performed. A marked inhibition of OC proliferation was observed at the presence of 1.0 µM of 2-ME, with the lowest value obtained after 48 h. However, at the end of the cells' incubation, maximally reduced proliferative response of OC was attributed to 2.0 µM of 2-ME. Simultaneously with the time of incubation the amount of Thy-1-positive cells decreased slightly from 50.5±1.4% to 31.5±3.6%. Contrary to 1.0 and 2.0 µM of 2-ME, its lowest value (0.5 µM) reduced Thy-1 positive cells after 48 hours. The same 2-ME concentration resulted in the elevation of the cell number expressing CK-19. In turn, the marked increase of albumine-positive cells was observed under 1.0 µM of 2-ME and reaching 21.5±6.2 % and 23.9±5.7% after 48 and 72 hours, respectively. Although the presence of 1.0 µM of 2-ME dramatically intensified apoptosis within 24 h of cell culture, the percentage of apoptotic cells remained unchanged under 2.0 µM of 2-ME. When subjected to the carcinogenic effect of CDE, 2-ME exerts anti-proliferative, proapoptotic, and differentiation effects in OC.

Effect of carotenoids on in vitro proliferation and differentiation of oval cells during neoplastic and non-neoplastic liver injuries in rats.

The goal of this study was to investigate the effects of beta-carotene and astaxanthin (ASX) - carotenoid without provitamin A activity on the proliferation and differentiation of rat oval cells (OC) in vitro. Oval cells were isolated from two groups of animals: I - partial hepatectomised (PH) and II- diethylnitrosamine (DEN) treated rats. At various time points cell lysates were separated by PAGE. For immunodetection primary antibodies against CD-34, Ck19 and albumin were used. Medium concentration of fibrinogen and haptoglobin was measured. Mitochondrial competence of cells was expressed as the proliferation index. In comparison to HP- and DEN-obtained oval cells cultured without carotenoids, the addition of beta-carotene and ASX increased albumin expression during the experimental period. The same condition didn't reveal CK19 expression. CD34 expressed by oval cells was detected up to the 5(th) week of beta-carotene and ASX absence in the medium. beta-carotene addition resulted in a decrease of the proliferative activity of OC, with significant changes in 48 h, the 5(th) and 15(th) week of incubation. ASX (p < or = 0.05) inhibited the proliferation, especially in 24h and 5(th) week of cell culture. In respect to haptoglobin concentration, its maximum value after the 10(th) week was observed. The fibrinogen level obtained from DEN-oval cells incubated with beta-carotene elevated from 480+/-6.87 microg/ml after 24h to 5520+/-34,56 microg/ml after the 15(th) week. In a condition without carotenoids fibrinogen concentration did not exceed 2280+/-31.5 microg/ml after the 15(th) week of cell culture.

Leptin influences histidine dipeptides and nitric oxide release from anterior pituitary cells of sheep in vitro.

Our previous results show that leptin, as well as nitric oxide (NO) and some antioxidants (histidine dipeptides - HDP) change the secretion of gonadotrophins from ovine adenohypophysis cells in vitro. NO and HDP are produced by pituitary and can modulate gonadotropin secretion by autocrine action. It is possible that these compounds mediate leptin influence on gonadotropin secretion. Therefore, the objective of the present study was to analyse leptin effect on NO and HDP (3-metyl-L-histidine, carnosine and anserine) release from ovine pituitary in vitro. Adenohypophysis cells were cultured in McCoy 5A medium with GnRH (4 x 10(-9) M) and 10(-10)-10(-5) M/l of leptin, respectively. Next, the media for analysis of NO (Griess method) and HDP (HPLC) were collected. Leptin in concentration of 10(-8)-10(-6) M/l caused a significant augmentation in NO in the culture medium, whereas in the dose of 10(-5) M/l reduced (P< or =0.05) NO release. The level of 3-metyl-L-histidine and anserine, but not carnosine, was significantly lower in the culture with 10(-8)-10(-7) M/l of leptin. Taking into account that 10(-8)-10(-7) M/l leptin stimulates LH and FSH secretion, as show in our previous study, it is possible that this effect in ewes is mediated by augmented release of NO and reduction of HDP level.

Concentrations of carnosine, anserine, L-histidine and 3-methyl histidine in boar spermatozoa and sheep milk by a modified HPLC method.

The present study deals with the application of high-performance-liquid-chromatography (HPLC) method for a quantitative detection of carnosine, anserine, L-histidine and 3-methyl-L-histidine in biological material with o-phthaldialdehyde (OPA) post column derivatisation at the constant temperature of 50 degrees C. For this purpose, some mobile-phases were prepared with scalar acetonitrile concentrations. A complete separation of all molecules, particularly for carnosine and 3-methyl-L-histidine, was obtained with a solution of acetonitrile and 6mM hydrochloric acid with 0.48 M sodium chloride (5%:95% v/v). Post column derivatisation reaction at temperature of 50'C permitted to obtain an increase in sensibility of all molecules. This method has been utilised for detection of histidine dipeptides in boar spermatozoa and in sheep milk. Concentrations (mean +/- S.E. nmol/10(9) spermatozoa) of carnosine (0.96 +/- 0.14) and anserine (0.83 +/- 0.18) in boar spermatozoa were significantly lower than those of L-histidine (52.85 +/- 4.86) and 3-methyl-L-histidine (83.07 +/- 7.1). Positive correlation was found between carnosine and anserine contents (r = 0.740; p < 0.01) and between L-histidine and 3-methyl-L-histidine (r = 0.657; p < 0.01). All histidine dipeptides studied were also present in 40 samples of sheep milk. In a case of samples without unit-forming colonies (UFC) of Staphylococcus coagulase-positive, carnosine concentrations (9.17 +/- 0.89 nmol/ml) were higher than anserine (0.51 +/- 0.02 nmol/ml) and both were significantly lower in respect to L-histidine (49.51 +/- 6.48 nmol/ml) and 3-metyl-L-histidine (81.21 +/- 6.82 nmol/ml). A negative correlation was observed between carnosine milk levels (r = -0.773; p < 0.01) and UFC/ml of Staphylococcus coagulase-positive. In conclusion this very simple and fast method can be used to detect histidine dipeptides in biological compartments where their concentrations are very low.

Fasting-induced changes in ovulation rate, plasma leptin, gonadotropins, GH, IGF-I and insulin concentrations during oestrus in ewes.

The aim of this experiment was to study the changes in the hormonal status and ovulation rate (OR) evoked by starvation during the follicular phase of the oestrous cycle in ewes. To achieve this goal, 12 female crossbreed sheep were synchronized and then half of them were fasted from the 12th to the 16th day of the oestrous cycle. On the 16th day, analysis of hormones and insulin-like growth factor-I (IGF-I) were performed in 10-min intervals. Then, on the 6th day of the following oestrous cycle, the OR in all ewes was determined by laparoscopy. Fasting reduced significantly (P < 0.05) the OR in ewes (1.25 +/- 0.50) in comparison with control (1.75 +/- 0.50). The drop in the OR was coincident with a significant (P < 0.001) decrease in the plasma concentration and pulse amplitude of leptin (0.29 +/- 0.08 ng/ml versus control 0.53 +/- 0.14 ng/ml), the plasma level of luteinizing hormone (LH) (0.19 +/- 0.06 IU/l versus 0.25 +/- 0.09 IU/l in control; P < 0.05) and the mean frequency of LH pulses (2.0/h versus 2.5/h in control). Fasting resulted also in a significant (P < 0.05) decrease in the plasma concentration and pulse amplitude of follicle stimulating hormone (FSH) in comparison with the control. Simultaneously, a significant (P < 0.001) drop in the IGF-I concentration in the fasted ewes (4.78 +/- 0.91 ng/ml) was found in comparison with control (7.63 +/- 1.85 ng/ml). Also the level of insulin were significantly (P < 0.001) lower in the fasted (178.99 +/- 39.08 pM/l respectively) than in the control sheep (302.66 +/- 49.01 pM/l respectively). Meanwhile, a double increase in the growth hormone (GH) pulses frequency and an augmentation in its plasma concentrations as a result of starvation was found. The obtained results shows that the acute fasting exerts an inhibitory effect on the ovulation rate in ewes coincident with suppression in leptin, FSH and LH secretion and changes in signalization mediated by GH.

The effect of interferon-tau and ovarian steroids on the proliferation of bovine endometrial cells in vitro.

The goal of this study was to evaluate the effect of various concentrations of interferon-tau (IFN-tau) with or without steroid hormones, 171 estradiol or progesterone, on the proliferation of bovine endometrial cells in vitro. Endometrial epithelial and stromal cells were isolated from the uterus of cows during the early estrus cycle (2-3 days) and incubated with different doses of IFN-tau with or without steroid hormones. The proliferation was determined by the MTT test in 48, 96, and 144 h of incubation. An antiproliferative activity of IFN-tau was observed both in epithelial and stromal cells cultured in RPMI 1640 medium supplemented with 10% FBS or. serum replacement. However, epithelial cells were more sensitive to antiproliferative action of interferon-tau. It;s activity was dose-and time-dependent. The inhibition of epithelial cell proliferation by 50% (ED50) was achieved at concentrations of 500 U/ml, 340 U/ml, and 8.8 U/ml of IFN-tau after 48, 96, and 144 h of incubation, respectively. None of the doses of IFN-tau (10-10.000 U/ml) used inhibited stromal cell proliferation in 50%. The most effective dose of IFN-tau inhibiting stromal cell proliferation was 10.000 U/ml, which decreased cell growth by 17.08%, 22.87%, and 2.6% after 48, 96, and 144 h of incubation, respectively. Steroid hormones, 17beta estradiol and progesterone, added to the culture of stromal cells with or without IFN-tau did not significantly modulate stromal cell growth. In contrast, a high concentration of progesterone (10(-5) M) alone significantly enhanced stromal cell growth. Progesterone at low, physiological concentrations (10(-7)- 10(-9) M) ameliorated the antiproliferative activity of IFN-tau, especially at the 10(-9 )M concentration. At this concentration, the stimulatory effect on stromal cell growth was observed. The mechanisms of such response are not entirely clear but may arise from the influence of IFN-tau on progesterone down regulation of its own receptor. Depicted activity of IFN-tau may find usefulness in therapy of neoplastic disorders.

Leptin effect on nitric oxide and GnRH-induced FSH secretion from ovine pituitary cells in vitro.

The secretion of gonadotrophins from anterior pituitary cells can be modulated by leptin and signals originating from the immune system, among others, by nitric oxide (NO). There are some studies that have demonstrated a role for leptin and NO in the regulation of FSH in rodents, however, no similar data are available in regards to ewes. Therefore, the objective of the present study was to analyse the leptin effect on GnRH-induced FSH secretion from the ovine anterior pituitary cells in vitro. Additionally, the influence of leptin on NO release and its role in the GnRH and leptin-modulated secretion of FSH from pituitary gland of ewes was investigated. The obtained results show that the influence of leptin on FSH secretion is biphasic. Leptin in concentration 10(-8) and 10(-7) M/l significantly enhances, whereas 10(-6) and 10(-5) M/l of leptin suppresses FSH secretion from the pituitary cells in comparison to the control. The secretion of FSH and NO release under the influence of leptin are in very high positive correlation (r=0.77). The inhibition of NO synthesis with L-NAME., instead, disables leptin from the stimulation of FSH secretion.

Effect of leukotoxin of Mannheimia haemolytica and LPS of E. coli on secretory response of bovine neutrophils in vitro.

To evaluate the role of leukotoxin (LKT) of Mannheimia haemolytica and lipopolysaccharide (LPS) of E. coli 055:B5 in pathogenesis of bovine respiratory disease (BRD) we investigated their in vitro effects on cultured bovine neutrophils. Functional parameters of neutrophils including degranulation, generation of superoxide, and nitric oxide were distorted in response to both toxins. The most essential reaction of neutrophils was found in respect to release of elastase after addition of LKT as well as LPS at concentration of 300 microg/ml. Moreover, we observed an increased release of myeloperoxidase (MPO) and alkaline phosphatase (ALK-P) from polymorphonuclear cells (PMN) after addition of LKT and LPS. We also found enhanced superoxide generation by bovine neutrophils after exposure to different concentrations of LKT and LPS. In cultures of PMN treated with LKT, concentration of nitrite increased with growing concentrations of LKT. Lower values of nitrite were obtained in cultures exposed to LPS. Partial lysis of PMN, determined by LDH (lactate dehydrogenase) leakage, started at concentration of 300 microg/ml for both toxins, meanwhile LKT concentration above 300 microg/ml was lethal. Our study has revealed that neutrophils in response to both toxins exaggerate release of analysed substances, which participate in worsening the course of the disease and play a role in lung injury during BRD. Toxins introduced to the cultural medium stimulate release of studied constituents from neutrophils by combined activation and lysis of neutrophils.

Assessment of neutrophil components as markers of lung injury in the course of bovine respiratory tract infections.

To define the role of activated neutrophils in lung injury during bovine respiratory tract infections (BRTI) their in vitro function was investigated. As a means to achieve this goal the comparison of secretory action between neutrophils from the BRTI group and control was made on the basis of elastase, myeloperoxidase (MPO), alkaline phosphatase (ALK-P) release, and nitric oxide production. We noted that there is an interdependence between secretory response of neutrophils and clinical severity of BRTI. The release of elastase was greater in the BRTI group than in the control group (49.17+/-4.41 versus 46.43+/-4.95% of the total content). Neutrophils from infected heifers exhibited a significantly (p<0.05) higher value of MPO release than from healthy heifers and reached 39.23+/-10.18 versus 25.54+/-8.41% of the total content. ALK-P containing granules released significantly (p<0.001) more enzyme in the group with BRTI than in the control group (22.42+/-6.27 versus 13.74+/-2.01% of the total enzyme content). The level of nitrite accumulation rose in the culture of cells isolated from heifers with BRTI from 4+/-0.53 microM after 0.5h to 6.9+/-0.52 microM after 72 h. Our data suggest that during BRTI the increase of neutrophil secretory action results in augmentation of enzyme release including elastase, MPO and ALK-P, and the nitrite production. During an excessive secretory response of neutrophils all these factors contribute to lung injury and worsen the course of a disease and might be recognised as markers of lung injury. Moreover, such a destructive action of neutrophils must be taken into account during the introduction of new methods of BRTI treatment.

Changes in the level of endogenous leptin, FSH, 17beta-oestradiol and metabolites during lupin-induced increase in ovulation rate in ewes.

The aim of the study was to determine the changes in the plasma concentration of leptin during lupin feeding-induced increase in the ovulation rate (OR) in ewes. Additionally, alterations in the plasma level of glycogenic amino acids and glucose (as the factors influencing leptin secretion) and the levels of follicle-stimulating hormone (FSH) and 17beta-oestradiol (E-2) (as the hormones regulated by leptin and engaged in recruitment, selection and development of ovulatory follicles) were analysed. Ninety-six female Polish Lowland Sheep were used. All ewes were cyclic and synchronized with PGF2alpha. The ewes were divided into two groups: control (n = 48), fed only with hay, and experimental (n = 48), received additionally lupin (Lupinus angustifolius) grain as a high-protein and a high-energy supplement. They were given lupin from the second to 13th day of the oestrous cycle at increasing doses (150-750 g/day per ewe). On the 11th day of cycle blood samples for analysis of hormones, amino acids and total glucose concentration, were collected from the jugular vein. OR was determined by laparoscopy of ovaries on the sixth day of the following oestrous cycle. Mean OR of ewes supplemented with lupin grain (1.687 +/- 0.463) was 30.67% higher than that of control (1.291 +/- 0.454). In spite of the unchanged body mass, a significant increase (P < or = 0.05) in mean concentration of plasma leptin in the experimental ewes [2.17 +/- 0.15 ng/ml human equivalent (HE)] was found in comparison with control (1.42 +/- 0.12 ng/ml HE). A significantly (P < or = 0.05) higher plasma FSH level in the ewes fed lupin (105.21 +/- 5.87 ng/ml) compared with those fed hay (67.88 +/- 6.03 ng/ml) was also found. However, plasma level of E-2 decreased after lupin feeding. Moreover, in the ewes fed lupin the plasma concentrations of glucose and nine glycogenic amino acids (Gly, Ala, Val, Met, Leu, Ile, Tyr, Phe and Arg) were increased. It can be concluded that lupin feeding exerts the stimulatory effect on the OR in Polish Lowland Sheep. The increase in OR is connected with significantly higher plasma leptin level and coincident with rise in FSH, glycogenic amino acids and glucose concentration. In contrast, the level of plasma E-2 was significantly decreased in lupin-fed ewes.

The response of bile secretion and ubiquinone Q10 to hyperglycaemia in sheep.

The aim of these investigations was to establish the secretion of ubiquinone Q10 (UQ10) in bile of sheep under glucose-induced cholestasis. Experiments were performed on 9 cannulated sheep divided into three groups: I-infused with sodium taurocholate, II-with Na-taurocholate plus glucose, III-with Na-taurocholate and glucose plus propranolol, phentolamine and atropine. Infusion of glucose increased plasma glucose concentration from 3.89 +/- 0.593 mM/l to 12.69 +/- 0.852 mM/l in 90 min and produced elevation of plasma insulin from 124.68 +/- 1.984 to 839.54 +/- 29.212 pM/l. Employment of blocking agents reduced insulin release to maximum 685.71 +/- 50.087 pM/l in 90 min. Under infusion of Na-taurocholate, bile flow averaged 14.016 +/- 0.706 microl/min/kg b wt. In the second group, bile flow decreased to 7.08 +/- 0.59 microl/min/kg b wt. in 90 min, and reached 11.25 +/- 0.25 microl/min/kg b wt in 240 min. Addition of the blocking agents in the third group, resulted in a significant (p < 0.05) decrease in bile flow to 3.733 +/- 0.680 microl/min/kg b wt in 105 min. This reduction of bile flow occurred with significant (p < 0.05) reduction of bile acids secretion that averaged 0.032 +/- 0.087 mM/min/kg in the first hour after glucose infusion and was maintained to the end of the experiment. Marked (p < 0.05) increase in UQ10 secretion was observed in both experimental groups. Maximum values of UQ10 secretion were obtained during the second hour of the experiment and averaged 0.449 +/- 0.196ng/min/kg b wt in the second, and 0.338 +/- 0.184ng/min/kg b wt in the third group of animals. Because at the end of the experiment UQ10 secretion gradually decreased we have concluded that free radicals generated during cholestasis lead to reduction of endogenous antioxidant capacity.

Relationships amongst liver bile salt clearance, bile secretion and infusion of lipids in calves.

In order to study the influence of portal lipid loading on the extraction rate of bile salts by the liver, four cholecystectomized calves (mean body weight 103 kg) were fitted with permanent cannulae to the common bile duct, duodenum and portal vein. A venflon catheter was also set up in the jugular vein to collect blood for analysis of fatty acids (FA) and bile salts (PBS) in plasma. The experiments were divided into two parts. In the first part sodium taurocholate (TCHNa) was infused for at least 2 h at a rate of 25 mumol/min into the duodenum to stabilize the bile flow and bile salt output in bile and the concentration in plasma. In the second part, as well as TCHNa, Intralipid (Itlp) (infusible 10% of lipid compounds) was also infused into the portal vein. Itlp was infused for 40 min, starting at a rate of 3 ml/min at the beginning of the 3rd hour of TCHNa infusion followed by a rate of 6 ml/min at the beginning of the 4th hour of TCHNa infusion. During TCHNa infusion the plasma bile salt concentrations were in the range 15.69-20.21 mumol/l, similar to that of the pre-infusion period. Introduction of Itlp to the infusion of TCHNa resulted in a significant (P < 0.05) increase of PBS, about 2 times higher at an Itlp infusion rate of 3 ml/min, and 3 times higher (62.82 +/- 16.42 mumol/l) at 6 ml/min. Under Itlp infusion, all common plasma FA increased, but the largest increases were in levels of linolenic, palmitic and oleic acids. During TCHNa infusion, the bile flow and the content of bile salts in bile did not change. The infusion of TCHNa with Itlp at the rate of 6 ml/min caused a 2-fold decrease both of the bile flow and of the output of bile salts from 18.58 +/- 3.04 microliters/min/kg and from 0.58 +/- 0.07 mumol/min/kg observed at the beginning of both infusions to 9.51 +/- 2.95 microliters/min/kg and 0.28 +/- 0.05 mumol/min/kg, respectively, at the end of the collecting period. When only TCHNa was infused, almost all of it was secreted to the bile, while with the additional infusion of Itlp only about half of the infused TCHNa was secreted to the bile. These results indicate that the extraction rate of PBS by the liver is decreased by loading of the portal blood by lipids, allowing more bile salts to escape into the systemic circulation, and thus reducing bile production.

Prochymosin polymorphism in calves of black-and-white cattle and their crosses with Simental bulls.

Polymorphism of prochymosin was observed in individual calf abomasa, using agarose gel electrophoresis followed by detection of proteolytic activity. Abomasum samples were randomly collected during slaughtering from 239 and 146 calves (3-5 weeks old) of Black-and-White cattle and their crosses with Simental bulls, respectively. Four distinct prochymosins were found and, according to their decreasing electrophoretic mobility in alkaline agarose gel, termed as prochymosin A, D, B and C which occurred singly and in pairs (then with equal proteolytic activities of both components). Prochymosin A, B and C (designation according to FOLTMANN, 1966) activated at pH 4.7 was transformed into electrophoretically distinct chymosin. When prochymosin D was activated at this pH, chymosin D showed similar mobility as chymosin B both at alkaline and acidic pHs. Prochymosin variants occurred at genetical equilibrium in nine and ten phenotypes in the first and second genetic group. The distribution of phenotypes in the two groups differed significantly (P < 0.05). The gene frequencies of prochymosin A, D, B and C were 0.35, 0.11, 0.52 and 0.02 in Black-and-White calves, and 0.39, 0.08, 0.47 and 0.06 in crosses, respectively. These prochymosins were controlled by four pairs of codominant alleles. A possible correlation of the results obtained by FOLTMANN (1966) with ours and those of ASATO and RAND (1972, 1977) was discussed.

Effects of sodium taurocholate and sodium dehydrocholate on bile flow, lipid and bilirubin secretion in sheep.

The investigation was performed on 8 sheep with implanted catheters in the common bile duct and in the cystic duct. Sodium taurocholate and sodium dehydrocholate were infused into the jugular vein at the rate of 50 mumol/min for 20 min. Directly after the termination of the sodium taurocholate infusion, the volume of the secreted bile increased from 8.4-9 microliters.kg-1.min-1 to the highest mean value of 17.8 microliters.kg-1, min-1, with a simultaneous increase in the concentration of cholates from 1.71 mmol/l to 4.82 mmol/l and bilirubin from 271.1 mumol/l to 461.7 mumol/l. The concentration of cholesterol and phospholipids in the bile also increased, but did not reach statistically significant values. The infusion of sodium dehydrocholate caused an increase in the bile secretion to the highest mean value of 20.59 microliters.kg-1.min-1 with a simultaneous decrease in the concentration of bilirubin to 148.75 mumol/l, cholesterol to 233.0 micrograms/ml, phospholipids to 56.11 micrograms/ml and cholate to 1.0 mmol/l. The results show that biliary secretion of phospholipids, cholesterol and bilirubin is dependent on the secretion of sodium taurocholate rather than on dehydrocholic acid.

Thermoregulatory effects and electrical conductivity in vagina of cow during oestrous cycle.

Measurement of vaginal temperature and electrical conductivity of cervicovaginal mucus were conducted in 20 dairy cows and were related to the phase of the oestrus cycle. Temperature and electrical conductivity in the anterior part of the vagina changed in synchronicity with phases of the oestrous cycle. About 12 hours before ovulation, the vaginal temperature increased from 37.94 +/- 0.33 degrees C to 39.00 +/- 0.64 degrees C, as compared to the pre-oestrus value. The occurrence of oestrus was accompanied by an increase in electrical conductivity of mucus in the anterior part of the vagina from 7.60 +/- 0.33 mS to 12.00 +/- 0.54 mS. Vaginal temperature dropped to 38.50 +/- 0.29 degrees C, and electrical conductivity dropped to 10.00 +/- 0.55 mS at ovulation time. Rises in vaginal temperature and electrical conductivity in the anterior part of the vagina were additional symptoms of oestrus and were followed by decrease in these values, indicating ovulation in cows.

[Effects of bile and bile acids on spontaneous motor activity of the small and large rabbit intestines in vitro]. / Efekty dzialania zólci i kwasów zólciowych na spontaniczna czynnosc motoryczna jelit cienkich i grubych królika in vitro.

The aim of our study was to describe the effects of bile and bile acids action on the spontaneous motor activity of the rabbit small and large intestines. The following fragments of intestines were used: duodenum, jejunum, ileum, caecum and colon of 25 rabbits of both sexes, weighing 2-3 kg. The motor activity of the isolated fragments of the intestines was recorded by the suspension method in a 300 ml container with oxygenated Krebs' solution, temp. 37 degrees C (constant), pH 7.8. The intestine was connected with the miograph constructed according to the Gillespie method. Vesicular bile was given in the amounts 0.3-10 ml per 1 l of the Krebs' solution. Chemically pure bile acids were also given as follows: cholic acid (Light) and chenodeoxycholic acid (Light) in the amount 500-1500 mumol/l of the Krebs' solution and lithocholic acid (Serva)--300-500 mumol/l. 0.33 ml/l of the Krebs' solution of the bile caused the threshold reaction, and only in the jejunum caused distinct inhibition of the motor activity. In duodenum, ileum and colon the inhibition time was very short, intestines quickly regained initial activity, and, what is more, frequency and amplitude of spasms were even greater. Big doses of the bile usually inhibited the motor activity of the studied intestine fragments, eliminating completely--with the exception of caecum--the spasms' amplitude, without releasing any relaxation reaction. As for the bile acids, the strongest inhibiting effect had lithocholic acid but, unlike bile, it caused the relaxation reaction.

[Effect of intra-duodenal administration of HCl and NaHCO3 on the secretion and content of sodium, potassium and calcium in the pancreatic juice and bile of sheep]. / Wplyw dodwunastniczego podawania HCl i NaHCO3 na wydzielanie i zawartosc sodu, potasu i wapnia w soku trzustkowym i zólci u owiec.

The experiments were carried out on 3 sheep with a Harrison type cannula inserted into the funds of the gall-bladder enabling to obtain bile and with a Herrera type cannula fixed in the duodenum enabling to sample pancreatic juice. Administration of 3 mEq HCl in 50 ml of solution to the duodenum increased the volume of secreted bile from 6,04 ml to 8,11 ml/15 min with no essential changes in the volume of pancreatic juice. Administration of 15 mEq NaHCO3 in 50 ml of solution decreased the volume of secreted bile from 6.73 ml to 4,15 ml/15 min and decreased pancreatic juice from 5,46 ml to 4.72 ml/15 min. Intravenous administration of secret increased the volume of both pancreatic juice and bile. Administration of HCl and NaHCO3 solution to the duodenum did not cause changes in the concentration and secretion of sodium, potassium and calcium in pancreatic juice and bile. The results point to the predominance of the secretory function of bile over pancreatic juice in sheep after stimulation of the duodenum with the investigated substances.