Plasmodium berghei: correlation of in vitro erythrophagocytosis with the dynamics of early-onset anemia and reticulocytosis in mice.

Infection of BALB/c mice with Plasmodium berghei results in an anemia which is excessive to that which can be accounted for solely by direct destruction of infected erythrocytes by the mature schizonts at the time of merozoite release. Mice infected with 10⁴ infected erythrocytes exhibited a progressive anemia beginning on Day 7. Significant reticulocytosis was first observed on Day 9 and parasitemia tended to parallel reticulocytosis with a lag of about 1 day. In studies of erythrophagocytosis, washed erythrocytes from randomly selected mice infected with 10⁵ infected red blood cells were phagocytized by peritoneal macrophages in vitro to a significantly greater extent on Days 3–5 postinfection than were erythrocytes taken from normal controls. The degree of erythrophagocytosis reached a peak on Day 4 and returned to control levels on Days 6 and 7. Erythrocytes taken from infected animals on Day 7 and incubated in normal plasma were phagocytized to a significantly greater extent than were normal erythrocytes incubated in normal plasma or erythrocytes from infected mice incubated in plasma from infected animals. The enhanced in vitro erythrophagocytosis observed on Days 3–5, which preceded and coincided with the beginning of the early-onset anemia on Day 5, may correlate with in vivo phenomena which may contribute to the developing anemia. Furthermore, the restoration of enhanced erythrophagocytosis by normal plasma seems to indicate that some component(s) of normal plasma may be depleted during the early stages of P. berghei infection.     

Trichinella spiralis: role of non-H-2 genes in resistance to primary infection in mice

Two strains of mice which share identical H-2 genes but differ in their genetic backgrounds were compared for their ability to resist infection with Trichinella spiralis. The two strains of mice, C3HeB/FeJ and AKR/J, share the H-2k haplotype which is associated with susceptibility to primary infection with T. spiralis in H-2 congenic strains of mice. AKR/J mice, infected with 150 infective muscle larvae, harbored significantly fewer muscle larvae 30 days postinfection than did mice of the strain C3HeB/FeJ. Approximately equal numbers of worms establish in the small intestine of AKR and C3H mice, but the AKR mice expelled adult worms from the gut more rapidly than did mice of the C3H strain. By Day 9 postinfection, 50% of the worms had been expelled by the AKR mice whereas expulsion of worms from C3H mice was delayed beyond Day 9 and occurred primarily between Days 10 and 12. Over this same experimental period (Days 6-12), fecundity of female worms from AKR mice, measured as the mean newborn larvae/female/hour, was approximately one-half that of worms taken from C3H mice. These results support the conclusion that genes outside of the mouse H-2 complex regulate expulsion of adult worms from the gut. These background genes also markedly influence the fecundity of female worms.     

Nippostrongylus brasiliensis: histamine and 5-hydroxytryptamine inhibition and worm expulsion

The daily administration of inhibitors of histamine and 5-hydroxytryptamine to rats infected with Nippostrongylus brasiliensis prevented the onset of the rapid phase of worm expulsion. These findings lend strong support to the importance of amine release and Mast cell discharge in worm expulsion.     

Trypanosoma congolense: calf erythrocyte survival.

Hereford calves infected with Trypanosoma congolense developed an anemia which was most severe 10 weeks after infection when packed cell volumes (PCV) averaged 21.1 ± 2.5% (±2 SE) as compared to 33.1 ± 2.1% for controls. At the termination of the study, at 28 weeks postinfection PCVs of infected animals had risen to 27.5 ± 1.0% as compared to 34.0 ± 1.7% for controls. In parallel with PCVs the apparent half-lives of ⁵¹Cr-labeled erythrocytes were reduced as early as the first 2 weeks postinfection. The greatest difference in erythrocyte half-lives between infected and control animals was found during the fourth to sixth weeks of infection when volumes for infected animals averaged 128 ± 46 hr as compared to 321 ± 30 hr for controls. During this period the parasitemia was at its highest level. At 28 weeks postinfection the average apparent half-life of infected animals was 243 ± 43 hr compared with 304 ± 11 hr for controls. No differences were observed in gastrointestinal loss of ⁵¹Cr between infected and control animals; however, urinary excretion of isotope was greatly increased in infected animals when compared to controls. No significant changes in total blood volumes were observed between infected and control animals but total plasma volumes increased and total erythrocyte volumes decreased significantly in infected animals.     

Trypanosoma musculi: Passive hemagglutination technique to measure antibody in mice

A passive hemagglutination assay was developed to measure Trypanosoma musculi-specific antibody in mice. Indicator-erythrocyte donor mice received 550 rad ⁶⁰Co 24 hr before intraperitoneal injection of 3 × 10⁴T. musculi. T. musculi antigen-coated erythrocytes were obtained from these mice on Day 9 postinfection. T. musculi antigen-coated erythrocytes obtained in this manner were used as indicator erythrocytes in a passive hemagglutination procedure. Serum from hyperimmunized mice (three consecutive infections at 21-day intervals) gave titers as high as 1:1024. Titers of 1:256 and 1:512 were obtained from singly infected mice on Days 18 and 28 postinfection, respectively. In marked contrast, nude mice infected with T. musculi did not produce a detectable agglutinating antibody response. Erythrocytes obtained from either irradiated (550 rad ⁶⁰Co) uninfected mice, nonirradiated infected mice, or normal mice did not agglutinate when combined with any of the sera tested. These data suggest the usefulness of this passive hemagglutination assay for the measurement of antibody to T. musculi in the serum of infected mice.     

Toxoplasma gondii: blood and tissue kinetics during acute and chronic infections in mice

Acute lethal infections were obtained in mice by intraperitoneal (IP) injection of 10(2) or 10(4) tachyzoites of the virulent RH and C56 strains. Chronic infections were obtained by IP injection or peroral (PO) gavage of 20 cysts of the avirulent C strain. Mice were sacrificed at varying intervals after infection and parasite burdens were quantitated in blood, brain, and lungs using a tissue culture method. Acutely infected mice died within 6 to 10 days postinfection as a function of the strain and inoculum size. With either strain, tachyzoites were first detected in lungs on either Days 2 or 4 postinfection, according to the inoculum size, then in brain and blood at Days 4 or 6; parasitic loads remained constantly at a higher level in lungs than in brain until the date of death. Bradyzoites could only be detected in lungs, from Days 4 or 6 until death. In chronic infections, similar results were obtained for IP and PO infected mice. Both tachyzoites and bradyzoites were first detected in lungs and brain from Day 7 after infection; tachyzoites remained at a higher level in lungs than in brain until Day 10, then subsequently decreased in lungs. At Day 50, tachyzoites were not detectable in lungs, whereas bradyzoites remained at a constant level; in brain, both parasitic stages were detectable at a similar level throughout the follow-up period. These results indicate that infection with a virulent Toxoplasma strain is characterized by an early involvement of lungs, with pneumonia as the principal cause of death.(ABSTRACT TRUNCATED AT 250 WORDS)     

Experimental acute Babesia caballi infections: I. Red blood cell dynamics

Hematological determinations were made on blood samples from six ponies acutely infected with two dosage levels of Babesia caballi (Group 1: divided into two subgroups of three ponies each). Similar determinations were made on blood samples from three premunized ponies given challenge inoculations (Group 2), and three equidae given uninfected red blood cells (Group 3).A trend towards decreases in RBC counts, hemoglobin concentrations, and hematocrits within one to four days after inoculation (AI) was observed in all groups. However, it was marked only in Group 1. In addition, only in Group 1 was there observed a concerted anemia occurring between Days 7 and 16.Those surviving ponies in Group 1 which developed a higher parasitemia between Days 5 and 6 AI (first parasitemia peak) developed a more severe anemia between Days 7 and 16. Ponies which developed parasitemias higher than 40 × 10³ parasitized cells/mm³ at the first parasitemia peak subsequently died.Free bilirubin in Group 1 animals increased immediately after inoculation, and repeatedly exceeded normal ranges until after Day 20 AI when the RBC counts were rising. Similar changes in free bilirubin did not occur in either Groups 2 or 3. Conjugated bilirubin levels did not exceed normal ranges in any of the experimental animals.Active erythrophagocytosis was evident in histological preparations of lymph node, spleen, liver, and lung from ponies which died. Cytosiderin pigment was present in liver parenchyma, and hematin was scattered throughout lymph nodes and spleen.     

Effects of anti-allergic drugs on intestinal mastocytosis and worm expulsion of rats infected with Neodiplostomum seoulense

The effects of anti-allergic drugs on intestinal mastocytosis and the expulsion of Neodiplostomum seoulense were observed in Sprague-Dawley rats, after oral infection with 500 metacercariae. The drugs used were hydroxyzine (a histamine receptor H1 blocker), cimetidine (a H2 blocker), cyclosporin-A (a helper T-cell suppressant), and prednisolone (a T- and B-cell suppressant). Infected, but untreated controls, and uninfected controls, were prepared. Worm recovery rate and intestinal mastocytosis were measured on weeks 1, 2, 3, 5, and 7 post-infection. Compared with the infected controls, worm expulsion was significantly (P < 0.05) delayed in hydroxyzine- and cimetidine-treated rats, despite mastocytosis being equally marked in the duodenum of all three groups. In the cyclosporin-A- and prednisolone-treated groups, mastocytosis was suppressed, but worm expulsion was only slightly delayed, without statistical significance. Our results suggest that binding of histamine to its receptors on intestinal smooth muscles is more important in terms of the expulsion of N. seoulense from rats than the levels of histamine alone, or mastocytosis.     

Nippostrongylus brasiliensis: Effect of cyclophosphamide treatment on worm expulsion in rats

The precise immunological mechanisms associated with expulsion of the gastrointestinal nematode Nippostrongylus brasiliensis remain controversial. In order to investigate the effects of drug-induced immunosuppression on parasite burdens and expulsion, various regimens of cyclophosphamide were administered to parasitized Wistar rats. It was observed that both the number of worms established from an infective dose of 3000 larvae and the time of expulsion were markedly increased with higher doses of cyclophosphamide. Thus, at the highest sublethal level of treatment (100 mg/kg), 82% of the infective dose was recovered at Day 9 postinfection compared with 51% in nontreated controls. Furthermore, in such treated rats expulsion was delayed in 6 days beyond that of nontreated animals. As cyclophosphamide, at the levels used in the present study, is known to primarily effect B-cell function, the results support the view that antibody-mediated responses play an essential role in worm expulsion.     

Trypanosoma lewisi and T. cruzi: Effect of infection on gestation in the rat

Termination of pregnancy occurred in the rat after infection with Trypanosoma lewisi early in gestation. Rats were inoculated on Day 2 of pregnancy and the uteri were excised and examined on Days 10 and 14 of gestation. There were no detectable differences in size in the fetuses of infected and control females at Day 10, but by Day 14 young of infected females were being reabsorbed, and their weight was markedly less than that of control young.A bioassay of estrogens and progestogens based on the decidual cell response indicated that there was a sufficient hormone level to maintain pregnancy beyond Day 10, so the mechanism of action by which fetal death was produced did not appear to be hormone depletion. The crucial changes in fetal weight occurred between Days 12 and 14 of gestation in rats infected with T. lewisi on Day 2 of gestation.Trypanosoma cruzi caused little or no pathologic change in the pregnant laboratory rat throghout the period of gestation and infected females gave birth to apparently normal young.     

Trypanosoma congolense: Thrombocyte survival in infected steers

Charolais steers infected with Trypanosoma congolense developed a thrombocytopenia that was first demonstrated shortly before the onset of parasitemia. The thrombocyte count progressively decreased from a level of 6 × 10⁵/mm³ on the 3rd day postinfection to l × 10⁵/mm³, its most depressed level, on the 11th day postinfection. The mean of the thrombocyte level of five infected bovines at the time of thrombocyte survival analysis was 195.6 ± 83.5 × 10³(± 2 SE) as compared to 998 ± 245.9 × 10³ in the control group. In parallel with depressed thrombocyte levels, the mean of the apparent half-lives of ⁵¹Cr-labeled thrombocytes was 1.3 ± 0.5 days as compared to 3.7 ± 0.5 days in control animals. A similar survival was noted in the apparent half-lives of ⁵¹Cr-labeled autologous and heterologous thrombocytes transfused to normal recipients.     

Experimental acute Babesia caballi infections: II. Response of platelets and fibrinogen

Ponies were acutely infected with Babesia caballi by inoculation with infected red blood cells (RBCs) containing 1 × 10⁸ and 1 × 10⁹ piroplasms. A series of blood samples taken before and after inoculation were analyzed for platelets and fibrinogen, and the results compared with similar analyses made on challenged, premunized ponies and on equids inoculated with uninfected RBCs. In acutely infected animals there were immediate decreases in platelet counts that persisted at least through Day 18 after inoculation (AI). Concomitantly, plasma fibrinogen levels rose, reaching peak values between Days 6–17. Clot retractions in vitro were impaired in these ponies during Days 9–16. No large diminutions in platelet counts or elevations of fibrinogen levels were observed in the challenged, premunized ponies or the group transfused with uninfected RBCs. In fact, the effect of challenge was to maintain or increase platelet counts. Our results plainly indicate that B. caballi can elicit alterations in clotting factor levels in its hosts during acute infections.     

Biomechanical properties of red blood cells infected by Plasmodium berghei ANKA

Malaria is a pathogenic disease in mammal species and typically causes destruction of red blood cells (RBCs). The malaria-infected RBCs undergoes alterations in morphology and its rheological properties, and the altered rheological properties of RBCs have a significant impact on disease pathophysiology. In this study, we investigated detailed topological and biomechanical properties of RBCs infected with malaria Plasmodium berghei ANKA using atomic force microscopy. Mouse (BALB/c) RBCs were obtained on Days 4, 10, and 14 after infection. We found that malaria-infected RBCs changed significantly in shape. The RBCs maintained a biconcave disk shape until Day 4 after infection and then became lopsided on Day 7 after infection. The central region of RBCs began to swell beginning on Day 10 after infection. More schizont stages were present on Days 10 and 14 compared with on Day 4. The malaria-infected RBCs also showed changes in mechanical properties and the cytoskeleton. The stiffness of infected RBCs increased 4.4–4.6-fold and their cytoskeletal F-actin level increased 18.99–67.85% compared with the control cells. The increase in F-actin depending on infection time was in good agreement with the increased stiffness of infected RBCs. Because more schizont stages were found at a late period of infection at Days 10 and 14, the significant changes in biomechanical properties might contribute to the destruction of RBCs, possibly resulting in the release of merozoites into the blood circulation.     

The protective capacities of fractionated immune thoracic duct lymphocytes against Nippostrongylus brasiliensis

Thoracic duct lymphocytes (TDL) obtained from rats either on the tenth day of a primary infection (Day 10 TDL) or 1 or 5 weeks after a tertiary infection (hyperimmune TDL) with Nippostrongylus brasiliensis were fractionated into cells lacking (sIg^?) or bearing (sIg⁺) surface immunoglobulin by a rosetting procedure. The abilities of unfractionated TDL, of the two subpopulations, and of the reconstituted cells to confer protection against the parasite were examined. The effector cells which cause worm expulsion were found only in (sIg^?) cells from Day 10 TDL and also predominantly in (sIg^?) cells from hyperimmune TDL. However, a small but significant degree of protection was conferred by (sIg⁺) cells from hyperimmune TDL. These results suggest that the mechanisms involved in worm expulsion are regulated by (sIg^?) cells but that (sIg⁺) cells from hyperimmune rats can also contribute to the mechanisms of worm expulsion.     

Hormonal changes during luteal regression in farmed fallow deer, Dama dama

Concentrations of progesterone, oxytocin and PGFM (pulmonary metabolite of PGF-2 alpha) were measured in plasma from peripheral blood samples collected from 5 fallow does every hour or 2 h for 12-h periods on Days 15-20 inclusive of the oestrous cycle (i.e. luteolysis). For 3 does that exhibited oestrus on Day 21, plasma progesterone concentrations fluctuated between 3 and 10 ng/ml on Days 15-18 inclusive. Thereafter, values declined progressively to attain minimum concentrations of less than 0.05 ng/ml on Day 20. Basal concentrations of plasma oxytocin and PGFM fluctuated between 5 and 20 pg/ml and 10 and 100 pg/ml respectively. Episodic pulses of plasma oxytocin (greater than 300 pg/ml) occurred on Days 15 and 16, whereas pulses of plasma PGFM (greater than 400 pg/ml) occurred on Days 19 and 20. There was little apparent correlation between episodic pulses of the two hormones. For 2 does that exhibited oestrus on Day 22, plasma progesterone concentrations declined to minimum values of 1.0-1.5 ng/ml by Day 20. One of these does showed very high levels of oxytocin secretion throughout the sampling period while the other showed an apparent paucity of oxytocin secretory periods. Two does hysterectomized on Day 13 of their second oestrous cycle failed to exhibit further oestrous cycles. Continual elevation of plasma progesterone concentrations (2-6 ng/ml) for an 8-month period indicated persistence of the corpus luteum after hysterectomy. It is concluded that luteolysis in fallow deer involves episodic secretion of both oxytocin and PGF-2 alpha.     

The role of endogenous estrogens in the maturation process of the bovine placenta

The plasma estrogen and progesterone concentrations of 19 pregnant cows (average duration of pregnancy 266.0 +/- 2.3 d at the start of the study) were determined daily from Day 6 pre partum to Day 1 post partum. Parturition was induced in all cows by administration of 10 mg i.m. flumethasone. Values were centered around the delivery date (Day 0) following either induced normal calving (n = 3) or surgical delivery (n = 16). In animals showing spontaneous expulsion of the fetal membranes (Group 1, n = 6) the average total estrogen concentration increased significantly from Day 6 until Day 1 before parturition (1329.2 +/- 317.9 to 3719.8 +/- 951.2 pg/ml in total estrogens). A marked decrease was observed on Day 1 post partum (459.4 +/- 344.2 pg/ml). In comparison with Group 1, animals showing either a delayed or partial expulsion of the fetal membranes, or in which the placenta could be withdrawn 16 h after calving (Group 2, n = 5), had consistently lower total estrogen concentrations between Day 6 (595.4 +/- 174.8 pg/ml) and Day 1 (1884.3 +/- 565.1 pg/ml) before parturition. The estrogen values of the cows with retained placenta (Group 3, n = 8) from Days 6 to 0 pre partum were significantly lower than those of Group 2. Total estrogen concentrations of the three groups 1 d post partum did not differ significantly. It is generally recognized that estrogens play an important role in the maturation process of the placentomes. Our investigation demonstrates that not only is the magnitude of the prepartum rise in estrogens of great influence of the maturation process but the duration of this rise is likewise important. These two factors are vital for a normal expulsion of the fetal membranes.     

Pathophysiologic alterations in Biomphalaria glabrata infected with Angiostrongylus costaricensis

Hemolymph glucose, alkaline phosphatase, lactic dehydrogenase, and creatine phosphokinase in Biomphalaria glabrata infected with Angiostrongylus costaricensis were significantly higher on day 27 postinfection (PI) than in uninfected snails. Hemolymph total calcium from infected snails was less on days 6, 12, and 27 PI than that from controls. Total hemolymph protein was similar for controls and infected animals during the entire study. Throughout the study the mean number of amoebocytes/mm³ hemolymph from infected snails was significantly less than that for controls. Mean total wet weights of digestive gland and foot muscle from infected and uninfected snails was similar throughout the study. Mean μg glycogen/mg wet weight of digestive gland from infected snails was significantly greater on days 24, 27, and 28 PI than that from controls. Mean μg glycogen/mg wet weight of foot muscle from infected snails was significantly reduced between days 12 and 28 PI from that of uninfected snails. It is suggested that hemolymph glucose and digestive gland glycogen in infected snails are augmented by glycogen breakdown in the foot muscle of parasitized animals. Elevations in hemolymph enzymes are due to tissue destruction by larvae emerging from the foot muscle of infected snails. Parasite-induced derangements in shell metabolism underlie observed changes in hemolymph calcium in infected snails.     

Luteal blood flow increases during the first three weeks of pregnancy in lactating dairy cows

The objectives of this experiment were to characterize luteal blood flow in pregnant and non-pregnant cows and to determine its value for early pregnancy diagnosis. Lactating dairy cows (n = 54), 5.2 ± 0.2 y old (mean ± SEM), average parity 2.4 ± 0.2, and ≥ 6 wk postpartum at the start of the study, were used. The corpus luteum (CL) was examined with transrectal color Doppler ultrasonography (10.0-MHz linear-array transducer) on Days 3, 6, 9, 11, 13, 15, 18, and 21 of the estrus cycle (estrus = Day 0). Artificially inseminated cows (n = 40) were retrospectively classified as pregnant (embryonic heartbeat on Day 25; n = 18), nonpregnant (interestrus interval 15 to 21 d, n = 18), or having an apparent early embryonic loss (interestrus interval >25 d, n = 4). There was a group by time interaction (P < 0.001) for luteal blood flow from Days 3 to 18; it was approximately 1.10 ± 0.08 cm² (mean ± SEM) on Day 3, and increased to approximately 2.00 ± 0.08 cm² on Day 13 (similar among groups). Thereafter, luteal blood flow was numerically (albeit not significantly) greater in pregnant cows, remained constant in those with apparent embryonic loss, and declined (not significantly) between Days 15 and 18 in nonpregnant cows. Luteal blood flow was greater in pregnant than in nonpregnant (P < 0.05) and nonbred cows (P < 0.05, n = 14) on Day 15 (2.50 ± 0.16, 2.01 ± 0.16, and 2.00 ± 0.18 cm², respectively) and on Day 18 (2.40 ± 0.19, 1.45 ± 0.19, and 0.95 ± 0.21 cm²). In cows with apparent early embryonic loss, luteal blood flow was 2.00 ± 0.34 and 2.05 ± 0.39 cm² on Days 15 and 18, which was less (not significantly) than in pregnant cows, but greater (P < 0.05) than in nonbred cows on Day 18. Although mean luteal blood flow was significantly greater in pregnant than nonpregnant (and nonbred) cows on Days 15 and 18, due to substantial variation among cows, it was not an appropriate diagnostic tool for pregnancy status.     

In situ characterization of mast cells in the frog Rana esculenta

The number, distribution, and ultrastructural characteristics of mast cells were assessed in the tongue, heart, and kidney of the frog Rana esculenta. The density of tongue mast cells (253±45 mast cells/mm²) was significantly higher than that of the heart (5.3±0.4/mm²) and kidney (15.3±1.4 /mm²). A striking feature of this study was the remarkable association of frog mast cells to nerves. The ultrastructural study of the mast cell/nerve association demonstrated that mast cells were closely apposed to or even embedded in nerves. Mast cells were also physically associated with melanocytes even in the heart. Mast cells were Alcian blue⁺/safranin⁺ in the tongue and in the peritoneum, whereas in the heart and in the kidney they were Alcian blue^–/safranin⁺. The mast cells in the lamina propria of the gastrointestinal tract were Alcian blue⁺/safranin^–. The cytoplasm of frog mast cells was packed with numerous heterogeneous, membrane-bound granules. The ultrastructure of these cytoplasmic granules was unique, being totally unlike any other previously described granules in other animal species as well as in man. The histamine content/frog mast cell (≈0.1 pg/cell) was approximately 30 times lower than that of human mast cells isolated from different tissues (≈3 pg/cell). A monoclonal anti-histamine antibody was used to confirm the ultrastructural localization of histamine in secretory granules in frog mast cells.     

兔前交叉韧带损伤后膝关节本体感觉、残端血运及膝关节腔尿激酶型纤溶酶原激活物变化的实验研究

摘要 目的：研究兔前交叉韧带（ACL）损伤后膝关节本体感觉、残端血运及膝关节腔尿激酶型纤溶酶原激活物（u-PA）的变化情况。方法：选取80只新西兰兔进行研究,将其以随机数字表法分作模型组及空白对照组各40只。模型组建立单侧ACL损伤模型,空白对照组仅切开关节。比较两组术前及术后2周、4周、8周时膝关节本体感觉、残端血运及膝关节腔u-PA水平的差异。结果：模型组新西兰兔术后2周、4周、8周时的体感诱发电位（SEP）、肌电图（EMG）潜伏期均高于空白对照组,而SEP、EMG波幅均低于空白对照组（P＜0.05）。模型组新西兰兔术后2周、4周、8周时的残端组织微血管密度分别为（2.04±0.24）n/mm²、（2.75±0.61）n/mm²、（1.60±0.33）n/mm²,均高于空白对照组的（1.34±0.24）n/mm²、（1.34±0.25）n/mm²、（1.35±0.26）n/mm²,差异均有统计学意义（P＜0.05）。模型组新西兰兔术后2周、4周、8周时的膝关节液u-PA水平分别为（173.97±14.29）pg/mL、（188.37±15.82）pg/mL、（171.38±14.76）pg/mL,均高于空白对照组的（158.02±10.18）pg/mL、（157.68±10.20）pg/mL、（157.37±10.07）pg/mL,差异均有统计学意义（P＜0.05）。结论：ACL损伤后会在不同程度上影响膝关节本体感觉、残端血运及膝关节腔u-PA含量,值得临床进一步研究。