O objetivo deste estudo foi avaliar o perfil proteico do plasma seminal equino utilizando eletroforese bidimensional de gel de acrilamida (2D-PAGE) e determinar se algumas das proteínas presentes estavam relacionadas com a congelabilidade do sêmen. O plasma seminal foi coletado de dez garanhões, de alta e baixa congelabilidade de sêmen, provenientes do Haras Estatal da Baixa Saxônia, na cidade de Celle, na Alemanha e rotineiramente utilizados em programas de inseminação artificial. Vinte e cinco bandas proteicas foram encontradas nos géis bidimensionais (12%) e sete delas foram identificadas por MALDI-MS. Das 25 proteínas encontradas nas amostras de plasma seminal dos garanhões, duas bandas proteicas apresentaram densidade óptica superior (P<0,05) nas amostras de garanhões de alta congelabilidade o sêmen: as bandas 5 (80-85 kDa, pI 7,54), que foi identificada como CRISP3 e a 45 (18,2 kDa, pI 5,0-5,2) identificada como HSP-2. Contrariamente a banda 7 (75,4 kDa, pI 6,9 – 7,4), identificada como lactoferrina, a 15 (26,7 kDa, pI 5,51) identificada como calicreína, a 25 (25 kDa, pI 7,54) como CRISP3 e a 35 (13,9 kDa, pI 3,8 – 4,2) que foi identificada como HSP-1, apresentaram valores de densidade óptica superior (P<0,05) nos reprodutores de baixa congelabilidade do sêmen. As proteínas foram identificadas através de espectometria de massa MALDI-MS. As evidências encontradas neste experimento mostram que existem diferenças no perfil proteico dos reprodutores de alta e baixa congelabilidade do sêmen, sugerindo as proteínas CRISP3 e a HSP-2 como possíveis marcadores da alta congelabilidade de sêmen de garanhões. / The objective of this study was to evaluate protein profile of equine seminal plasma using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and to find if any of these proteins were related to semen freezability. Seminal plasma was collected from 10 stallions of high and low semen freezability routinely used in AI programs from the State Stud of Lower Saxony and Artificial Insemination Center. Twenty five protein spots were identified from the 2 D gel (12%), seven of which were present in all samples. Of the 25 proteins found in the research stallions, two spots showed superior relative content (P<0.05) in seminal plasma samples collected from stallions with high semen freezability: the spots 5 (80-85 kDa, pI 7.54) was identified as CRISP3 and 45 (18.2 kDa, pI 5.0-5.2) was identified as HSP-2. Conversely, the spot 7 (75.4 kDa, pI 6.9 – 7.4) was identified as lactoferrin, 15 (26.7 kDa, pI 5.51) was identified as kallikrein, 25 (25 kDa, pI 7.54) was identified as CRISP3 and 35 (13.9 kDa, pI 3.8 – 4.2) was identified as HSP-1, showed superior relative protein content (P<0.05) on seminal plasma samples from stallions with low semen freezability. The proteins were identified by MALDI-MS. There were differences in the seminal plasma protein profile between stallions with high and low semen freezability. It may be suggested that CRISP3 and HSP-2 may be considered possible seminal plasma markers of high semen freezability.

Das Schädel-Hirn-Trauma (SHT) entsteht durch äußere Gewalteinwirkung auf den Kopf und verursacht mechanisch eine Schädigung des Hirngewebes. Zusätzlich tragen sekundäre Pathomechanismen, wie Entzündungsprozesse und die Schädigung der Blut-Hirn-Schranke (BHS), dazu bei, dass sich das initial geschädigte Läsionsareal im Laufe der Zeit vergrößert. Vor allem bei jungen Erwachsenen ist das SHT eine der häufigsten Ursachen für bleibende Behinderungen und Todesfälle. Aufgrund der schweren Auswirkungen des SHT und der bislang fehlenden Therapieoptionen ist die Identifizierung neuer Zielstrukturen für eine kausale Therapie von größter Bedeutung. Ausgehend von tierexperimentellen Studien ist das Kallikrein-Kinin-System (KKS) ein besonders erfolgversprechender Angriffspunkt zur Behandlung des SHT. Die Aktivierung des KKS über den Gerinnungsfaktor XII (FXII) und die darauf folgende Bildung von Bradykinin sind mit dem Entstehen von Hirnödemen und Entzündungsreaktionen assoziiert. Vorangegangene Studien haben weiterhin die Frage aufgeworfen, ob und in welchem Maße thrombotische Prozesse einen Einfluss auf die Pathophysiologie und die sekundären Hirnschädigungen nach SHT haben. Da FXII sowohl das KKS als auch die intrinsische plasmatische Gerinnungskaskade initiiert und somit zur Fibrinbildung beiträgt, stand FXII im Mittelpunkt der Untersuchungen dieser Dissertation. Die vorliegende Arbeit beschäftigt sich mit den Fragen, (I) inwiefern FXII eine Rolle bei der sekundären Hirnschädigung nach Trauma spielt und (II) ob thrombotische Prozesse ein pathophysiologisches Merkmal nach Trauma darstellen. In zwei unterschiedlichen Trauma-Modellen wurden FXII-defiziente Tiere und mit einem spezifischen Inhibitor des aktivierten FXII (FXIIa) behandelte Tiere gegen Kontrolltiere nach SHT verglichen. Die Analyse der funktionellen Ausfallerscheinungen und des Ausmaßes an neuronaler Degeneration zeigte, dass FXII-Defizienz und FXIIa-Inhibition vor den Auswirkungen eines SHT schützen. Als zugrundeliegende Mechanismen wurden die Reduktion von thrombotisch verschlossenen Gefäßen in der Mikrovaskulatur des Gehirns sowie der Schutz vor BHS-Störungen und verringerte inflammatorische Prozesse identifiziert. Weiterhin wurde festgestellt, dass eine Blockade der intrinsischen Gerinnungskaskade über FXII keine intrazerebralen Blutungen auslöst. In Gewebeproben von Patienten mit SHT wurde gezeigt, dass Thrombozytenaggregate auch im klinischen Verlauf auftreten und sich somit die tierexperimentellen Befunde auf die humane Situation übertragen lassen. Insgesamt tragen die Ergebnisse dazu bei, die komplexen und vielfältigen Pathomechanismen nach SHT besser zu verstehen und vor allem die Relevanz thrombo-inflammatorischer Prozesse nach SHT aufzuzeigen. Die gezielte Blockade des FXII(a) könnte als therapeutisches Prinzip zur Abschwächung der Sekundärschaden nach SHT geeignet sein. / Traumatic brain injury (TBI) is the result of an outside force causing mechanical disruption of the brain tissue. In addition, delayed pathogenic events, like inflammatory processes and blood-brain barrier damage occur, which collectively exacerbate the injury. In young adults, TBI is one of the main reasons for permanent disability and death. Because of its severe consequences and the lack of causal treatment, the identification of novel therapeutic options is of utmost importance. Based on animal studies, the kallikrein-kinin-system (KKS) is a very promising target to treat secondary injury processes following TBI. The activation of the KKS via coagulation factor XII (FXII) and the subsequent formation of bradykinin are tightly associated with the development of brain edema and inflammation. Recent studies have raised the question to what extent thrombotic processes might influence the pathophysiology and secondary injury processes following TBI. As FXII is not only the starting point of the KKS, but also the initiator of the intrinsic coagulation cascade which leads to fibrin formation, FXII was the center of interest for this dissertation. The work presented here deals with the issue, (I) whether FXII plays a role in the development and aggravation of secondary injury processes after trauma and (II) if thrombotic processes display a pathophysiological feature in TBI. In two different models of brain trauma, FXII-deficient mice and mice treated with a specific inhibitor of activated FXII (FXIIa) were compared to their respective control groups after trauma induction. The analyses of the functional outcome and the amount of neurodegenerative processes showed a distinct amelioration in favor of the genetically modified and treated animals. As underlying mechanisms, the reduction of thrombotic vessels in the brain microvasculature and additionally, protection from blood-brain barrier damages and less inflammation were identified. Moreover, it was observed that interference with the intrinsic coagulation cascade via FXII does not lead to the formation of intracerebral bleedings. The evaluation of human brain tissue surgically obtained following TBI demonstrated that platelet aggregates occur regularly in the course of brain trauma and that they seem to contribute to the secondary injury processes and the ischemia-like injury pattern. Taken together, the results contribute to the understanding of the highly complex and heterogeneous pathomechanisms following TBI, especially concerning thrombo-inflammatory processes. The targeted pharmacological blocking of FXII(a) could be a useful therapeutic principle in the treatment of TBI-associated pathologic processes.

Introduction. The outermost layer of the epidermis, the stratum corneum (SC), plays a fundamental role in our defense against microorganisms, chemicals, and dehydration. The SC is composed of tightly packed keratinized skin cells, corneocytes. For a functioning skin it is essential that corneocytes are constantly shed (desquamated). Kallikrein-related peptidase (KLK) 5 and KLK7 may be important in the desquamation process through degradation of desmosomal proteins. Severe hereditary diseases, where inhibition of KLK5 and/or KLK7 is missing, points to the importance of regulation of protease activity. KLKs may be regulated in various ways: tissue expression, activation of proforms, specific inhibitors, and physico-chemical properties like pH. Besides their involvement in desquamation, KLKs may also be important in immune defense and inflammation by processing of mediators and via activation of proteinase-activated receptors (PARs). Aims. 1. To identify and characterize previously unknown proteases in the SC. 2. To further characterize KLK5 and KLK7 with special focus on activation mechanisms. 3. To identify new inhibitors of KLKs in human SC. 4. To further characterize KLKs regarding effects of various inhibitors and substrates. 5. To study possible functions of KLKs in inflammation, in particular via activation of PAR-2. Methods. Plantar SC was used as a source for purification of proteins. Recombinant proteins were produced in different expression systems (insect cells, yeast cells, and bacteria). Different activity assays and kinetic studies were performed. Tissue expression was studied by immunohistochemistry, immunoblot and PCR. PAR-2 activation was studied by measurement of intracellular [Ca2+] and immunofluorescense in KNRK-PAR2 cells. Results. Active KLK14 was purified from extracts of plantar SC. KLK14 showed a superior catalytic efficiency as compared to KLK5 when measuring trypsin-like activity. This indicated that KLK14, despite being present in low amounts in skin, may have great relevance for skin physiology. Among enzymes tested only KLK5 showed autocatalytic activity and is so far the only enzyme found in SC that can activate proKLK7. KLK5 could also activate proKLK14. This together with studies of pH dependence on activation placed KLK5 as a possible key activating enzyme in a proposed proteolytic cascade in the SC. In plantar SC extracts we have also identified the novel Kazal-type serine protease inhibitor 9 (SPINK9). Our results indicate that SPINK9 is preferentially expressed in palmo-plantar skin and specific for KLK5. Differences found regarding substrate specificity and inhibition profile can be useful in evaluating the contribution of individual KLKs to the proteolytic activity in crude SC extracts. One interesting finding was that KLK8, present at high protein levels in the epidermis, could not be inhibited by any protease inhibitor found in the extracts. PAR-2 activation studies showed that KLK5 and 14 but neither KLK7 nor 8 can activate PAR-2. Immunohistochemistry preferentially detected KLK14 in intraepidermal parts of the sweat ducts and in dermal sweat glands but we could also show coexpression of KLK14 and PAR-2 in the SC and stratum granulosum of the epidermis in inflammatory skin disorders. To summarize, KLK involvement in desquamation may be dependent on a proteolytic activation cascade regulated by an intrinsic pH gradient and specific inhibitors present in SC. Another possible function of KLKs is as mediators of inflammation through activation of PAR-2.

Activated coagulation Factor XII (FXIIa) elevates blood pressure (BP) acutely by stimulating adrenomedullary catecholamine (CA) release in Brown Norway (BN) bioassay rats. These effects are absent in kininogen-deficient BN Katholiek (BNK) bioassay rats, indicating that these FXIIa-induced responses require an intact kallikrein-kinin system (KKS). In three hypertensive anephric pediatric patients, ΔFXIIa concentrations tracked peri-dialytic ΔBP. We hypothesized that FXIIa exerts a vasoconstrictor pro-hypertensive action, via the KKS, particularly evident in chronic renal failure (CRF). In CRF patients (n=11) receiving conventional hemodialysis, mean plasma FXIIa concentrations were 3-fold (p<0.05) greater than in healthy controls. Although conversion from conventional to nocturnal hemodialysis did not change mean FXIIa concentrations there was intra-session variation within individuals, such that ΔFXIIa concentrations correlated with changes in mean arterial pressure (MAP, r=0.66, p=0.026) and total peripheral resistance (TPR, r=0.75, p=0.007). In normotensive BN rats, FXIIa infusion (85 ng/min/kg for 60 mins) increased MAP (10±1 mmHg), TPR (0.5±0.1 Units), and CA, whilst left-ventricular end-diastolic volume (LVEDV) and heart rate decreased (all p<0.05). After adrenalectomy, FXIIa infusion decreased MAP (5±1 mmHg), did not raise CA or induce sustained vasoconstriction, and caused a greater fall in LVEDV (all p<0.05). In the 5/6 nephrectomized (NX) rodent CRF model, MAP and TPR were significantly greater in BN NX (n=16) than in BNK NX (n=15) (147±4 vs. 133±2 mmHg, 2.8±0.2 vs. 2.3±0.2 Units; all p<0.05). Plasma FXIIa measured using our semi-quantitive ELISA was 3-fold higher in both BN NX and BNK NX than in controls (p<0.01), but only correlated with MAP (r=0.48, p=0.01) in the BN NX. Plasma CA were elevated in the BN NX (p<0.05) but not in BNK NX. Infusion of a specific FXIIa inhibitor into BN NX decreased MAP (-12 mmHg) and TPR (-0.5 Units) proportionally to baseline FXIIa (ΔMAP: r=-0.72, p=0.002; ΔTPR: r=-0.57, p=0.021), and plasma CA fell by 40-67% (all p<0.05). No such changes occurred in the BNK NX. In summary, a significant component of the hypertension of CRF can be attributed to FXIIa-induced vasoconstriction mediated via the KKS and stimulated CA release. In normal rats, FXIIa appears also to directly or indirectly decrease preload and heart rate.

Activated coagulation Factor XII (FXIIa) elevates blood pressure (BP) acutely by stimulating adrenomedullary catecholamine (CA) release in Brown Norway (BN) bioassay rats. These effects are absent in kininogen-deficient BN Katholiek (BNK) bioassay rats, indicating that these FXIIa-induced responses require an intact kallikrein-kinin system (KKS). In three hypertensive anephric pediatric patients, ΔFXIIa concentrations tracked peri-dialytic ΔBP. We hypothesized that FXIIa exerts a vasoconstrictor pro-hypertensive action, via the KKS, particularly evident in chronic renal failure (CRF). In CRF patients (n=11) receiving conventional hemodialysis, mean plasma FXIIa concentrations were 3-fold (p<0.05) greater than in healthy controls. Although conversion from conventional to nocturnal hemodialysis did not change mean FXIIa concentrations there was intra-session variation within individuals, such that ΔFXIIa concentrations correlated with changes in mean arterial pressure (MAP, r=0.66, p=0.026) and total peripheral resistance (TPR, r=0.75, p=0.007). In normotensive BN rats, FXIIa infusion (85 ng/min/kg for 60 mins) increased MAP (10±1 mmHg), TPR (0.5±0.1 Units), and CA, whilst left-ventricular end-diastolic volume (LVEDV) and heart rate decreased (all p<0.05). After adrenalectomy, FXIIa infusion decreased MAP (5±1 mmHg), did not raise CA or induce sustained vasoconstriction, and caused a greater fall in LVEDV (all p<0.05). In the 5/6 nephrectomized (NX) rodent CRF model, MAP and TPR were significantly greater in BN NX (n=16) than in BNK NX (n=15) (147±4 vs. 133±2 mmHg, 2.8±0.2 vs. 2.3±0.2 Units; all p<0.05). Plasma FXIIa measured using our semi-quantitive ELISA was 3-fold higher in both BN NX and BNK NX than in controls (p<0.01), but only correlated with MAP (r=0.48, p=0.01) in the BN NX. Plasma CA were elevated in the BN NX (p<0.05) but not in BNK NX. Infusion of a specific FXIIa inhibitor into BN NX decreased MAP (-12 mmHg) and TPR (-0.5 Units) proportionally to baseline FXIIa (ΔMAP: r=-0.72, p=0.002; ΔTPR: r=-0.57, p=0.021), and plasma CA fell by 40-67% (all p<0.05). No such changes occurred in the BNK NX. In summary, a significant component of the hypertension of CRF can be attributed to FXIIa-induced vasoconstriction mediated via the KKS and stimulated CA release. In normal rats, FXIIa appears also to directly or indirectly decrease preload and heart rate.

This thesis consists of three main parts. An introduction to diode-pumped solid-state lasers, thermal modelling of solid-state lasers and rate-equation modelling of solid-state lasers. The first part explains the basic components and operation principles of a typical diode-end-pumped solid-state laser. The stimulated emission process, solid-state laser gain media, various pump geometries and a basic end-pumped laser resonator configuration are among the topics that are explained. Since thermal effects are one of the main limiting factors in the power-scaling of diode-pumped solid-state lasers, the second part of this thesis describes numerical and analytical thermal models that determine the thermal lens and thermally induced stresses in a laser crystal. As a first step, a time-independent numerical thermal model which calculates the three-dimensional temperature distribution in the laser crystal is implemented. In order to calculate the time dependent thermally induced stresses in a laser crystal, a coupled thermal-stress finite element analysis model was implemented. Even though some steady-state analytical solutions for simple crystal geometries do exist, the finite element analysis approach was taken so that the time dependent thermally induced stresses could be calculated for birefringent crystals of various geometries. In order to validate the numerical results, they are compared to experimental data and analytical solutions where possible. In the last part, the population dynamics inside the laser gain medium are described and modelled with a quasi-three-level rate-equation model. A comprehensive spatially resolved rate-equation model is developed and discussed. In order to simplify the implementation of the rate-equation model as a computer simulation, the spatial dependence of the laser parameters is ignored so that the model reduces to a singleelement plane-wave model. The simplified rate-equation model is implemented and solved numerically. The model is applied to a four-level CW and Q-switched Nd:YLF laser as well as a quasi-three-level QCW Tm:GdV04 laser. The models' predictions are thoroughly verified with experimental results and also with analytical solutions where possible. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, Durban, 2007.

Inflammation is the normal biological response to tissue injury, and is characterised by the interactive activation of multiple mediators and cell types. One response to tissue injury is the production of pain, not only by direct trauma to sensory fibres, but also through the release of mediators from sensory nerve terminals. One such mediator is kinin which is a vasoactive peptide considered to play a primary role in inflammation by causing constriction of venules, dilation of arterioles, increasing permeability of the capillary membrane, and interacting with sensory nerve terminal transmitters to evoke pain. The kinin forming enzymes (kallikreins) reach inflammation sites either on the surface of migrating neutrophils or by transudation from plasma. The kininogen molecule which contains the kinin moiety, has been localised on the external surface of the neutrophil, and provides the substrate from which kinins can be cleaved through enzymatic action. The cellular actions of kinins are mediated through B2 receptors, which are also located on the external surface of the neutrophils. In addition, the induced effects of kinins are regulated by B1 receptors. The formation of nitric oxide (NO) from arginine released from the kinin C terminus, and receptor membrane signal transduction by nitric oxide following kinin receptor activation is discussed. A molecular response to cell injury is the formation of chemotactic mediators that attract neutrophils to sites of inflammation. The question whether neutrophils contribute to circulating levels of kinins was examined in infections and inflammatory disorders. This novel hypothesis was tested using circulating neutrophils harvested from patients with tuberculosis meningitis and pneumonia. These neutrophils showed a distinct loss of only the kinin moiety from the kininogen molecule located on the external surface. The confocal images of fixed, permeabilised neutrophils provided multi-dimensional constructs, and the intensity of fluorescence reflected the relative amounts of the molecule present in both neutrophils harvested from healthy volunteers as well as patient blood. The immunocytochemical labelling experiments using colloidal gold as markers, confirmed, at the ultrastructural level, the presence or disappearance of the kinin moiety from the kininogen molecule on the neutrophil surface. The cell component of synovial fluid in rheumatoid athritis (RA) consists mainly of neutrophils. This study demonstrates the absence of the kinin moiety from circulating and synovial fluid neutrophils from patients with RA, as well as an increased signal from immunolabelled B2 receptors in synovial fluid neutrophils. These findings support the hypothesis that in RA, kinins are released during the inflammatory response in the joints, and suggests that there is an upregulation of the B2 receptor at the site of inflammation. Neutrophils chemotactically drawn to the site of inflammation become activated to release kinin from the kininogen molecule, and thereafter re-enter the circulation where they were harvested systemically. B2 receptors may be upregulated following activation by kinins or by other mediators present in the inflammatory milieu. Interleukin-1 has been shown to upregulate kinin receptors on human synovial cells. Anti-peptide antibodies to the loops of cloned B1 and B2 receptors have provided powerful probes for the cellular identification of the two kinin receptor families. Mapping of the B2 receptors showed upregulation on the neutrophils gathered from inflamed joints. However, no activation of the Br receptors was observed in normal blood neutrophils as well as those obtained from the different disease states. / Thesis (M.Med.)-University of Natal, 1996.

The family of human kallikrein-related peptidases (KLKs) numbers 15 serine proteinases implicated in tumour progression. Despite the wide tissue distribution of KLKs and the numerous reports of their differential expression in pathological settings, the signalling mechanism(s) whereby these enzymes regulate tissue function are not yet known. Further, knowledge of the levels of their activity, as well as of their potential endogenous targets, has only been extracted from in vitro studies and cell culture systems. We hypothesized that KLKs can trigger tumour signalling via proteinase-activated receptors (PARs), a family of G-protein-coupled receptors. To test our hypothesis, we evaluated the ability of KLKs 5, 6, and 14: to activate or prevent signalling via PARs 1, 2, and 4 in cells and tissues expressing these receptors. Further, we used a novel activity-based probe approach, coupled with conventional immunoassay (ELISA), to determine the abundance of active KLK6 relative to total immunoreactive KLK6 in cancer-related biological fluids. We concluded that KLKs can regulate multiple signalling pathways triggered by PARs 1, 2, and 4, resulting in calcium release, platelet aggregation and vascular relaxation, and they can cause murine inflammation. Further, our activity-based ELISA demonstrated the presence of active KLK6 in ovarian cancer ascites fluids and cancer cell supernatants. We, therefore, suggest that tumours can produce active KLKs, which can potentially control tumour behaviour by regulating PAR activity.

O objetivo deste estudo foi avaliar o perfil proteico do plasma seminal equino utilizando eletroforese bidimensional de gel de acrilamida (2D-PAGE) e determinar se algumas das proteínas presentes estavam relacionadas com a congelabilidade do sêmen. O plasma seminal foi coletado de dez garanhões, de alta e baixa congelabilidade de sêmen, provenientes do Haras Estatal da Baixa Saxônia, na cidade de Celle, na Alemanha e rotineiramente utilizados em programas de inseminação artificial. Vinte e cinco bandas proteicas foram encontradas nos géis bidimensionais (12%) e sete delas foram identificadas por MALDI-MS. Das 25 proteínas encontradas nas amostras de plasma seminal dos garanhões, duas bandas proteicas apresentaram densidade óptica superior (P<0,05) nas amostras de garanhões de alta congelabilidade o sêmen: as bandas 5 (80-85 kDa, pI 7,54), que foi identificada como CRISP3 e a 45 (18,2 kDa, pI 5,0-5,2) identificada como HSP-2. Contrariamente a banda 7 (75,4 kDa, pI 6,9 – 7,4), identificada como lactoferrina, a 15 (26,7 kDa, pI 5,51) identificada como calicreína, a 25 (25 kDa, pI 7,54) como CRISP3 e a 35 (13,9 kDa, pI 3,8 – 4,2) que foi identificada como HSP-1, apresentaram valores de densidade óptica superior (P<0,05) nos reprodutores de baixa congelabilidade do sêmen. As proteínas foram identificadas através de espectometria de massa MALDI-MS. As evidências encontradas neste experimento mostram que existem diferenças no perfil proteico dos reprodutores de alta e baixa congelabilidade do sêmen, sugerindo as proteínas CRISP3 e a HSP-2 como possíveis marcadores da alta congelabilidade de sêmen de garanhões. / The objective of this study was to evaluate protein profile of equine seminal plasma using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and to find if any of these proteins were related to semen freezability. Seminal plasma was collected from 10 stallions of high and low semen freezability routinely used in AI programs from the State Stud of Lower Saxony and Artificial Insemination Center. Twenty five protein spots were identified from the 2 D gel (12%), seven of which were present in all samples. Of the 25 proteins found in the research stallions, two spots showed superior relative content (P<0.05) in seminal plasma samples collected from stallions with high semen freezability: the spots 5 (80-85 kDa, pI 7.54) was identified as CRISP3 and 45 (18.2 kDa, pI 5.0-5.2) was identified as HSP-2. Conversely, the spot 7 (75.4 kDa, pI 6.9 – 7.4) was identified as lactoferrin, 15 (26.7 kDa, pI 5.51) was identified as kallikrein, 25 (25 kDa, pI 7.54) was identified as CRISP3 and 35 (13.9 kDa, pI 3.8 – 4.2) was identified as HSP-1, showed superior relative protein content (P<0.05) on seminal plasma samples from stallions with low semen freezability. The proteins were identified by MALDI-MS. There were differences in the seminal plasma protein profile between stallions with high and low semen freezability. It may be suggested that CRISP3 and HSP-2 may be considered possible seminal plasma markers of high semen freezability.

O objetivo deste estudo foi avaliar o perfil proteico do plasma seminal equino utilizando eletroforese bidimensional de gel de acrilamida (2D-PAGE) e determinar se algumas das proteínas presentes estavam relacionadas com a congelabilidade do sêmen. O plasma seminal foi coletado de dez garanhões, de alta e baixa congelabilidade de sêmen, provenientes do Haras Estatal da Baixa Saxônia, na cidade de Celle, na Alemanha e rotineiramente utilizados em programas de inseminação artificial. Vinte e cinco bandas proteicas foram encontradas nos géis bidimensionais (12%) e sete delas foram identificadas por MALDI-MS. Das 25 proteínas encontradas nas amostras de plasma seminal dos garanhões, duas bandas proteicas apresentaram densidade óptica superior (P<0,05) nas amostras de garanhões de alta congelabilidade o sêmen: as bandas 5 (80-85 kDa, pI 7,54), que foi identificada como CRISP3 e a 45 (18,2 kDa, pI 5,0-5,2) identificada como HSP-2. Contrariamente a banda 7 (75,4 kDa, pI 6,9 – 7,4), identificada como lactoferrina, a 15 (26,7 kDa, pI 5,51) identificada como calicreína, a 25 (25 kDa, pI 7,54) como CRISP3 e a 35 (13,9 kDa, pI 3,8 – 4,2) que foi identificada como HSP-1, apresentaram valores de densidade óptica superior (P<0,05) nos reprodutores de baixa congelabilidade do sêmen. As proteínas foram identificadas através de espectometria de massa MALDI-MS. As evidências encontradas neste experimento mostram que existem diferenças no perfil proteico dos reprodutores de alta e baixa congelabilidade do sêmen, sugerindo as proteínas CRISP3 e a HSP-2 como possíveis marcadores da alta congelabilidade de sêmen de garanhões. / The objective of this study was to evaluate protein profile of equine seminal plasma using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and to find if any of these proteins were related to semen freezability. Seminal plasma was collected from 10 stallions of high and low semen freezability routinely used in AI programs from the State Stud of Lower Saxony and Artificial Insemination Center. Twenty five protein spots were identified from the 2 D gel (12%), seven of which were present in all samples. Of the 25 proteins found in the research stallions, two spots showed superior relative content (P<0.05) in seminal plasma samples collected from stallions with high semen freezability: the spots 5 (80-85 kDa, pI 7.54) was identified as CRISP3 and 45 (18.2 kDa, pI 5.0-5.2) was identified as HSP-2. Conversely, the spot 7 (75.4 kDa, pI 6.9 – 7.4) was identified as lactoferrin, 15 (26.7 kDa, pI 5.51) was identified as kallikrein, 25 (25 kDa, pI 7.54) was identified as CRISP3 and 35 (13.9 kDa, pI 3.8 – 4.2) was identified as HSP-1, showed superior relative protein content (P<0.05) on seminal plasma samples from stallions with low semen freezability. The proteins were identified by MALDI-MS. There were differences in the seminal plasma protein profile between stallions with high and low semen freezability. It may be suggested that CRISP3 and HSP-2 may be considered possible seminal plasma markers of high semen freezability.