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Summary. Plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI), against t-PA (t-PAI) or u-PA (u-PAI), in spermatozoa and seminal plasma as well as testosterone in the blood of Friesland, Chios, and Karagouniki rams all showed a seasonal variation with the highest values during the corresponding breeding season of the ewes (Autumn-Winter). The seasonal variation of PAA and PAI in spermatozoa or seminal plasma as well as blood testosterone was different among the three breeds studied. Increased spermatozoal PAA was observed in November and May in Friesland rams, in October and November in Chios rams, and in October in Karagouniki rams. Spermatozoal t-PAI was increased in December and June in Friesland rams, in November and December in Chios rams, and in November in Karagouniki rams. Spermatozoal u-PAI was increased in December in Friesland rams, in October and December in Chios rams, and in November and December in Karagouniki rams. Plasminogen activator activity and PAI in seminal plasma also showed similar seasonal variations. Plasminogen activator activity and PAI in spermatozoa and seminal plasma showed a positive correlation with blood testosterone. The results of the present study support our previous findings on the possible role of spermatozoal PAA and PAI in the fertilizing ability of spermatozoa.

After a single injection of serum gonadotrophin (PMSG) at the dose of 15 IU/kg, i.m. into rams testosterone in the plasma of blood showed a significant rise between 4th and 7th day post-injection. At the same time (4th-7th day) the plasminogen activator activity (PAA) in seminal plasma was found to be increased, but the plasminogen activator inhibition (PAI) expressed against t-PA (anti-t-PA) showed an increase between 32nd and 46th day. In spermatozoa a marked increase of PAA was revealed between 32nd and 46th day post-injection, while an increase of PAI (anti-t-PA) was exhibited on the 74th day. Plasmin inhibition (PI) in seminal plasma and spermatozoa showed no change compared to controls. A positive correlation has been found between increased concentrations of testosterone and PAA or PAI (anti-t-PA) in spermatozoa and seminal plasma. The induced increase of PAA in spermatozoa under the effect of testosterone might be of physiological importance, since PAA is localized to sperm membranes and might participate in the whole process of fertilization.

Organochlorine pesticides and polychlorinated biphenyls are widely used in agriculture and industry, respectively. The present study assessed the burden of environmental pollutants in the follicular fluid of farm animals (cattle, sheep, goats, and pigs). An analytical method combining a solid-phase extraction with (C(18)) for clean-up and GC-electron capture detection using a capillary column was implemented for isolation and determination of organochlorine pesticides and polychlorinated biphenyls (PCBs). Of the organochlorine pesticides, hexachlorobenzene (HCB), hexachlorocyclohexane (HCH, alpha-, beta-, and gamma-isomers), dieldrin, heptachlor epoxide, and the DDT-related chemicals (o,p'-DDE, p,p'-DDE, p,p'-DDD, p,p'-DDT) were detected and of the PCBs, the congeners PCB-52, -101, -138, -153, and -180 were detected. In all species of farm animals, the most frequently detected pollutant was gamma-HCH (90-100% of samples) followed by HCB (80-100%), and p,p'-DDE (75-90.91%). Species differences in the concentrations of HCB, beta-HCH, heptachlor epoxide, and DDT-related chemicals in follicular fluid were noted as well as differences in the concentrations of some pollutants within the same species.

The aim of the study was to investigate the effect of dexamethasone on plasminogen activator activity (PAA), t-PA antigen level, plasminogen activator inhibition (PAI) and plasmin inhibition (PI) in ram lymphocytes. The PAA of ram lymphocytes was due to t-PA (tissue-type plasminogen activator), but not to u-PA (urokinase-type plasminogen activator). Dexamethasone at the dose of 3 mg kg ˇ1 increased the PAA and t-PA antigen level of lymphocytes within 2 h after administration, while decreased the PAI 6‐14 h after administration; no change in PI was noted. When dexamethasone was administered at the dose of 0.75 mg kg ˇ1 every 4 h for 12 h, PAA and t-PA antigen level of lymphocytes showed an increase 2‐6 h after the end of the administration, while PAI and PI remained unchanged. These changes in PAA or PAI of lymphocytes, dependent on the dose or the pattern of dexamethasone administration, may be of importance regarding the role of lymphocytes and PAA or PAI in several pathophysiological conditions. # 1999 Elsevier Science B.V. All rights reserved.

Inhalt Vergleichende Untersuchungen ovarieller Steroide im Blut sowie spezifische proteolytische Enzyme im Zervikalmukus bei vier Schafrassen nach Ostrussynchronisation (Progesteron und PMSG). 2. Rassebedingte Unterschiede fur PAA, PAI und PI im Zervikalmukus wahrend des normalen und des synchronisierten Ostrus sowie des ersten Ostrus nach der Synchronisation Plasminogen-Aktivator-Aktivitat (PAA), Plasminogen-Aktivator-Inhibition (PAI) und Plasmin-Inhibition (PI) wurden im Zervikalmukus von vier verschiedenen Schafrassen (Friesland, Chios, Serres, Karagouniki) wahrend des normalen und synchronisierten Ostrus sowie des ersten Ostrus nach der Synchronisation untersucht. PAA-Konzentrationen stiegen in der Mitte des normalen Ostrus an. Dabei traten rassespezifische Unterschiede auf. Ebenfalls rasseabhangig war die Veranderung von PAA im Zervikalmukus bei synchronisierten Tieren. Diese Veranderung bestand auch im ersten Ostrus nach der Synchronisation bei allen Rassen auser bei Friesland-Schafen. Es traten beide Typen des des Plasminogen-Aktivator (t-PA und u-PA) auf. Rasseabhangig stieg PAI zur Mitte und am Ende des normalen Ostrus an. Ostrus-Synchronisation veranderte PAI. Diese Veranderung hielt auch wahrend des auf die Synchronisation folgenden Ostrus an. PI stieg zum Ende des naturlichen Ostrus an, wobei einige Rasseunterschiede beobachtet wurden. Im synchronisierten Ostrus veranderten sich die PI-Werte im Zervikalmukus. Auser bei Friesland-Schafen hielt diese Veranderung des PI wahrend des ersten Zyklus nach der Synchronisation an. Die Blutkonzentrationen von Ostradiol-17subten im begrenzten Mase bei einigen Rassen einen positiven Effekt auf PAA bzw. PAI und einen negativen Effekt auf PI im Zervikalmukus aus. Contents Plasminogen-activator activity (PAA), plasminogen-activator inhibition (PAI), and plasmin inhibition (PI) were studied in the cervical mucus of four sheep breeds (Friesland, Chios, Serres, Karagouniki) during natural oestrus, synchronized oestrus, and the first oestrus after synchronized oestrus. PAA had increased by the middle of natural oestrus, but with some differences among the breeds studied. Oestrous synchronization disturbed PAA in the cervical mucus, dep- ending again on the breed. This disturbance persisted during the first oestrus after the synchronized oestrus in all breeds studied except Friesland. PAA in the cervical mucus of the ewe was due to both types of plasminogen activator (t-PA and U-PA). PAI in the cervical mucus had increased by the middle and end of natural oestrus, depending on the breed. Oestrous synchronization disturbed PAI, which was still the case even during the first oestrus after synchronized oestrus. PI had increased by the end of natural oestrus with some differences among the breeds studied. In all breeds studied, PI in the cervical mucus was disturbed during the synchronized oestrus. This disturbance of PI persisted, more or less, during the first oestrus after synchronized oestrus in all breeds studied except Friesland. Blood oestradiol-17β, in a quite limited range of concen-trations dependent on the breed and the type of the oestrus, could positively affect PAA or PA1 and negatively affect PI in the cervical mucus.

In normal Friesland rams, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) in spermatozoa and seminal plasma, plasmin inhibition (PI) in seminal plasma and testosterone concentration in blood all showed seasonal variation. In a Friesland ram with chromosomal chimaerism XX/XY, however, although PAA, PAI and PI in seminal plasma and testosterone in the blood exhibited the same seasonal variation as in normal rams, in spermatozoa the PAA and PAI showed no seasonal variation. This is the first case in which a chromosomal anomaly has been linked with abnormal patterns in PAA and PAI.

After the manifestation of mass terrorism at the 9/11 attack against the United States of America and the following terrorist assaults in Morocco, Saudi Arabia, Turkey and Spain, the provision of security to the 2004 Olympic Games came to be discussed in a new light. In Greece, in particular, responding to such threats became a matter of national defense. Although there was no specific intelligence indicating a specific terrorist threat to the Athens Olympic Games of 2004, the countering of such an eventuality gained prominence. Since it was widely assumed that this required the decisive engagement of military power, the Hellenic Armed Forces (HAF) planned, in every detail, the application of military countermeasures against any potential terrorist threat from the air, the ground and the sea.

Greece during and after World War II successively tried to rid itself from foreign (Italian and German) and communist influence. In its fight for independence, it was aided by the United Kingdom and the United States, but after World War II the communist threat, Greece being on the border to the communist sphere of influence, remained eminent. Therefore, Greece had to demonstrate solidarity and had to militarily participate in the alliance against communism around the world, that is, in North Korea. Greece formed a “Special Expeditionary Force” (GEF), involving ground and air forces. A special branch of high commanding officers, under a senior officer, was formed to play the role of liaison officer to the UN General Command Headquarters (GCHQs) for the Far East based in Tokyo-Japan. The Greek participation in the Korean War was highly recognized by the South Koreans as well as by the allied forces and the United Nations. Participating allies acknowledge and appreciate the valor, bravery, self-sacrifice, and resourcefulness of the Greek soldiers and officers.

The effect of unilateral and bilateral adrenalectomy, unilateral and bilateral demedullation or unilateral adrenalectomy/unilateral demedullation on tissue plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) was studied in the rat. All the above treatments induced an increase of PAA in lungs. Increased PAA was also noted in brain after bilateral adrenalectomy or demedullation, as well as unilateral adrenalectomy/unilateral demedullation. In kidneys the PAA was decreased after bilateral adrenalectomy or demedullation and unilateral adrenalectomy/unilateral demedullation. In aorta only after bilateral adrenalectomy a decreased PAA was induced. In heart and liver no changes in PAA were noted. A decreased PAI expressed against tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) was found in lungs of all treated rats compared to controls. However, an increased PAI was noted in heart, liver and aorta against t-PA or u-PA after bilateral adrenalectomy and in liver after bilateral demedullation as well as after unilateral adrenalectomy/unilateral demedullation (rats with only one adrenal cortex). A dissociation between anti-t-PA and anti-u-PA response was seen in heart, liver and aorta. A variable change in PI was induced in kidneys, aorta, lungs and brain in all treatments except unilateral demedullation or unilateral adrenalectomy. Therefore, the effect of adrenalectomy or demedullation on tissue PAA, PAI and PI was variable and dependent on the extent of the treatment (unilateral or bilateral), the organ as well as the time after the treatment.

Plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) have been studied with spectrophotometric methods in extracts of human, bovine, ovine and rat kidneys of both sexes. In all species studied, renal PAA (cortex or medulla) was higher in females than in males. The PAA was also higher in the medulla than in the cortex in all species and both sexes. The PAA was due to both types of plasminogen activator; tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA). In the human kidney (cortex or medulla) the measurement of t-PA antigen showed that t-PA is higher in females than in males; t-PA is also higher in the medulla than in the cortex in both sexes. The PAI showed the opposite pattern in all species studied; it was lower in females than in males. It was also lower in the medulla than in the cortex. PAI-1 was identified in the human kidney. Sex-related differences in renal PAA or PAI almost disappeared after bilateral orchidectomy in rats. PI showed no sex or regional differences in the species studied. Sex-related differences in renal PAA and PAI in man and various animal species might be of physiological or pathophysiological importance.

In the normal stomach of male rats marked differences in plasminogen activator activity (PAA) and plasmin inhibition (PI), but not in plasminogen activator inhibition (PAI), were noted among cardiac area, body and pyloric region. Chronic ethanol consumption (for 15 or 30 days) at the concentration of 6% or 12% in the drinking water induced an increase in PAA in the pyloric region and the body of the stomach (the higher concentration after 15 days and both concentrations after 30 days). The response was time- and dose-dependent. At the cardiac area no change of PAA was noted. Ethanol at both concentrations induced after 30 days a decreased PAI in the pyloric region and the body of the stomach, which was expressed against u-PA, but not against t-PA. A decreased PI was noted at both concentrations of ethanol after 30 days only in the pyloric region. Therefore, changes in PAA, PAI and PI after chronic ethanol consumption were dependent on the concentration, the period of the consumption and the area along the gastric wall.

The aim of the present study was to investigate the effect of melatonin on plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) in ram spermatozoa and seminal plasma, in correlation with changes in blood testosterone. Melatonin implants (18 mg) were placed subcutaneously in sixteen Chios rams in autumn and spring. Semen samples for spectrophotometrical assays were collected 36 h before the implantation of melatonin and thereafter once a week, for 17 weeks. Blood samples for testosterone assay (RIA) were collected 8h before implantation (one sample/30 min x 7.5 h) and thereafter every 15 days for 105 days after implantation. For each ram, six parameters of testosterone were estimated: mean value, basal level, number of peaks, peak amplitude, peak duration and mean testosterone concentration during peaks. Melatonin implantation during autumn induced an increase in PAA and t-PAI in spermatozoa; melatonin implantation in spring induced an additional increase in u-PAI and PI; no change in PAA, PAI or PI was found in seminal plasma, during autumn or spring. The melatonin-induced increase of PAA, PAI and PI in spermatozoa was in positive correlation with the increase of testosterone mean value, basal level and number of peaks; the increase of testosterone parameters was greater in autumn compared to spring. Changes of PAA, PAI and PI of spermatozoa, under the influence of melatonin, might indicate changes in the fertilizing ability of spermatozoa, since plasminogen activators and their inhibitors are present on the plasma and the outer acrosomal membrane of spermatozoa and are released during the acrosome reaction.

In a series of consecutive blood sampling in 15 days intervals over 15 weeks after implantation of melatonin in rams an increased mean value, basal level and number of peaks of testosterone was observed in samples of the third fortnight (45th day). This increase was greater in the autumn (breeding season) than in spring (non-breeding season). Total acrosin activity in spermatozoa was increased between days 35-56 (autumn) and days 49-70 (spring) after implantation and the relative increase was higher in autumn than in spring. The increase of acrosin activity was independent of the changes of testosterone. An increase of acrosin activity by melatonin, in cases of low activity, might improve fertilization rates in sheep not only during the breeding season, but also during the non-breeding season (after oestrus induction).

The objective of this study was to evaluate the effect of alpha-tocopherol on blood testosterone and specific proteolytic enzymes in spermatozoa and seminal plasma, with final aim the increase of sperm fertilizing ability with a nutritional supplement. The effect of alpha-tocopherol supplementation on testosterone parameters (mean value, basal level, peak number, mean concentration value during peaks, peak amplitude, peak duration) and plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) of spermatozoa and seminal plasma was studied in the ram during autumn (estrous period for the sheep in Greece) and spring (anestrous period). Treated animals showed a marked increase in serum alpha-tocopherol. Testosterone parameters were not affected by the alpha-tocopherol in either autumn or spring, however, the spermatozoal PAA and PAI (anti-tPA) were increased in the spring but not in autumn. These enzymes and their inhibitors are normally increased in autumn (the breeding season) and low in spring. If PAA can improve the fertilizing ability of spermatozoa in the spring, our finding may mean that a nutritional supplement, such as alpha-tocopherol, could provide rams for an accelerated onset of the breeding season in the ewe.

The effect of aspirin or endotoxin or aspirin plus endotoxin on the circadian variations of plasminogen activator activity (PAA), tissue-type plasminogen activator (t-PA) antigen level, plasminogen activator inhibition (PAI) and plasmin inhibition (PI) in aorta, heart and brain of the rat was studied. In aorta the circadian variations of PAA, t-PA antigen and tissue-type PAI (t-PAI) were blunted by endotoxin, while the circadian variation of PI was reversed; t-PAI variation was blunted by aspirin plus endotoxin, while PI variation was reversed. Various disturbances of the circadian variations of PAA, t-PA antigen, PAI or PI in heart and brain were also observed. In conclusion, the circadian variations of fibrinolytic parameters in key organs are influenced by aspirin or endotoxin or aspirin plus endotoxin in a varying way or degree depending on the treatment, the parameter studied or the organ.

Plasminogen activator activity (PAA), t-PA antigen level, plasminogen activator inhibition (PAI) and plasmin inhibition (PI) showed a circadian variation in rat aorta, heart, brain and lungs of both sexes, but in a different way depending on the organ and the fibrinolytic parameter studied and the sex as well. In general, the lowest values of PAA and t-PA antigen were found in the early morning and the highest values in late afternoon, while PAI or PI showed the opposite pattern (with the exception of lungs). In kidneys and liver the fibrinolytic parameters studied showed no circadian variation. Sex-related differences, mostly quantitative, were noted in aorta, heart, brain and kidneys, with lower PAA and t-PA antigen and higher PAI or PI in the male than in the female.

Unilateral or bilateral ovariectomy was performed in young and adult rats. Mainly bilateral ovariectomy induced variable changes of plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) in key organs (brain, lungs, heart, aorta and kidneys). The most remarkable changes were induced after bilateral ovariectomy performed in young animals and mostly after two and three months of ovariectomy. Therefore, the effect of ovariectomy on tissue PAA, PAI or PI was variable and dependent on the extent of the ovariectomy (unilateral or bilateral), the age of the animal at ovariectomy (young or adult), the time after ovariectomy, and the organ. An additional interesting finding was the dissociation in the response of tissue anti-t-PA and anti-u-PA activities to ovariectomy in some of the organs studied.

The transplacental effect of lead compounds (lead acetate and tetraethyl lead) on the tissue plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) was studied in the rat. The concentration of lead in organs of the newborn showed a great variation; the distribution of lead in the organs studied depended on the dose and the stage of gestation at injection. In each organ the concentration of lead was dose-dependent. In control specimens no lead could be detected. The tissue response of PAA, PAI and PI to the lead compounds also showed a great variation; however, there was no correlation between lead concentrations and PAA, PAI or PI responses. Changes of one or more of the parameters studied (PAA, PAI or PI) were noticed in lungs, liver, heart, brain and kidneys. The PAA was due to the tissue type plasminogen activator in all organs studied; in kidneys and lungs the urokinase type of plasminogen activator was also detected. Therefore, fetal tissue PAA, PAI and PI can be affected transplacentally by lead compounds.