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Noncardiogenic pulmonary edema associated with protamine administration during coronary artery bypass graft surgery.

Protamine sulfate is the only agent approved to reverse heparin-induced anticoagulation. As with any other drug, protamine has the potential to cause adverse effects that range from mild hypotension to potentially fatal events, such as noncardiogenic pulmonary edema (NCPE) and catastrophic pulmonary vasoconstriction. We report a case of NCPE after the administration of protamine to a patient undergoing coronary artery bypass graft surgery and discuss the diagnosis and management of this severe adverse event.

Aged↗

Low-dose heparin appears safe and can eliminate protamine use for carotid endarterectomy.

OBJECTIVE: To determine the morbidity associated with carotid endarterectomy (CEA) when low doses of heparin (30 U/kg) are used for anticoagulation. This technique eliminates the need for protamine and its potentially deleterious effects on some patients. DESIGN: A retrospective chart review. SETTING: A large academic medical center. PARTICIPANTS: The records of 420 consecutive CEAs in 337 patients (83 bilateral procedures). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The amount of heparin used was less than that used in most reported studies. Eighty-two percent of patients received only 2,000 U of heparin for their entire operation (range, 500 to 3,000 U). Complication rates were low. Neurologic complications included a 0.95% incidence of nonfatal stroke and a 2.1% incidence of transient neurologic deficits that resolved in the first day. There was no mortality. The wounds were described in the postoperative period as dry (96%), swollen (3%), or bloody (1%). No patients received protamine. CONCLUSION: The use of 5 to 10,000 U of heparin will provide anticoagulation for more than an hour. In CEA surgery, anticoagulation for this duration is often unnecessary. A smaller dose of heparin (30 U/kg) can provide adequate anticoagulation for this procedure while eliminating the potentially deleterious effects of protamine use. No additional morbidity was attributed to this technique.

Anticoagulants↗

Improved planar amperometric nitric oxide sensor based on platinized platinum anode. 2. Direct real-time measurement of NO generated from porcine kidney slices in the presence of l-arginine, l-arginine polymers, and protamine.

Nitric oxide generation from porcine kidney slices is assessed using a new planar NO-selective amperometric sensor. The planar shape of the sensor allows for direct NO measurements near the surface (10 microm) of renal tissue slices in real time. Renal NO production may be modulated by the addition of L-arginine, arginine homopolymers (R2, R6, R10), and protamine, all of which can potentially transport across cellular membranes and provide a substrate for nitric oxide synthase within kidney parenchyma. Real-time amperometric measurements demonstrate that most L-arginine species can translocate across the cell membrane and rapidly increase NO production. However, no increase in NO generation is observed when the dimer of L-arginine (R2) is added to the solution bathing the tissue, suggesting that this species cannot permeate cell membranes. The degree of enhancement in NO generation observed for L-arginine and the larger peptides depends on the structure and follows the following sequence: R10 (decamer) > protamine > R6 (hexamer) > L-arginine. Protamine and the R10 decamer, especially, induce the largest increases in NO generation owing to their apparent rapid translocation into cells and subsequent cleavage by proteases to create high intracellular levels of L-arginine. The effect of sensor size (for sensor dimensions of 0.15- and 1-mm outer diameters) on the measured surface NO levels is also examined. The larger sensor traps more NO but hinders access of the L-arginine species to the tissue area between the flat distal plane of the sensor and the surface of the kidney slice. The use of such NO-generating peptides may be important in numerous biological systems that depend on NO production, such as ischemia-reperfusion injury and thrombogenesis.

Animals↗

Response characteristics of a reversible electrochemical sensor for the polyion protamine.

We describe here in detail the first reversible electrochemical sensors for the polyion protamine. Potentiometric sensors were proposed in recent years, mainly for the determination of the polyions heparin and protamine. Such potentiometric polyion sensors functioned on the nonequilibrium extraction of polyions into a hydrophobic membrane phase via ion pairing with lipophilic ion exchangers. This made it difficult to design sensors that operate in a truly reversible fashion. The reversible sensors described here utilize the same basic response mechanism as their potentiometric counterparts, but the processes of extraction and ion stripping are now fully controlled electrochemically. Spontaneous polyion extraction is avoided by using membranes containing highly lipophilic electrolytes that possess no ion-exchange properties. Reversible extraction of polyions is induced if a constant current pulse of fixed duration is applied across the membrane, followed by a baseline potential pulse. The key theoretical response principles of this new class of polyion sensors are discussed here and compared to those of its classical potentiometric counterpart. The electrochemical sensing system is characterized in terms of optimal working conditions, membrane composition, selectivity, and influence of sample stirring and organic-phase diffusion coefficient on the response characteristics. Excellent potential stability and reversibility of the sensors are observed, and measurements of heparin concentration in whole blood samples via protamine titration are demonstrated.

Biosensing Techniques↗

Purification and characterization of cytoplasmic protamine messenger ribonucleoprotein particles from rainbow trout testis cells.

Poly(A)-containing protamine messenger ribonucleoprotein particles [poly(A+) pmRNP particles] have been isolated from the polysomal and free cytoplasmic subcellular fractions of trout testis cells by a two-step isolation procedure. Ethylenediaminetetraacetic acid (EDTA) treated particles from both cytoplasmic fractions were first fractionated by sucrose gradient centrifugation and the putative pmRNP particles localized by utilizing 3H-labeled protamine complementary DNA (pcDNA) probes. In addition, particles present in these fractions were characterized by their translational activity in the heterologous, rabbit reticulocyte cell-free system and the protein components of crude mRNP complexes analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoesis. The final purification step involved affinity chromatography of pooled gradient fractions on oligo(dT)-cellulose from which intact pmRNP could be eluted with distilled water at 40 degrees C. Highly purified particles from both polysomal and free cytoplasmic fractions prepared by this procedure had buoyant densities of 1.35-1.37 g/cm3 in CsCl or a protein content of approximately 82%. Particles isolated from EDTA-dissociated polysomes were actively translated in vitro, while their free cytoplasmic counterparts were not. High salt washed pmRNP particles or the RNA extracted from pmRNP preparations, however, directed the synthesis of trout protamines in this system. A model of the activation of stored pmRNP particles in vitro and in vivo is presented.

Animals↗

Lead interaction with human protamine (HP2) as a mechanism of male reproductive toxicity.

During spermatogenesis, histones are replaced by protamines, which condense and protect sperm DNA. In humans, zinc contributes to sperm chromatin stability and binds to protamine P2 (HP2). Chemical interactions with nuclear protamines, which prevent normal sperm chromatin condensation, may induce changes in the sperm genome and thus affect fertility and offspring development. Since lead has a high affinity for zinc-containing proteins, we investigated lead interactions with HP2 as a novel mechanism of its toxicity to sperm. UV/vis and CD spectroscopy results indicated that HP2 binds Pb(2+) at two different sites, causing a conformational change in the protein. They also provided evidence that thiol groups are primarily involved in Zn(2+) and Pb(2+) binding to HP2 and that HP2 may have additional binding sites for Pb(2+) not related to Zn(2+). HP2 affinities for Pb(2+) and Zn(2+) were very similar, suggesting that Pb(2+) can compete with or replace Zn(2+) in HP2 in vivo. This interaction of lead with HP2 resulted in a dose-dependent decrease in the extent of HP2-DNA binding, although lead interaction with DNA also contributed to this effect. Therefore, the ability of lead to decrease the level of HP2-DNA interaction may result in alterations to sperm chromatin condensation, and thus in reduced fertility.

Animals↗

alpha-Helix-double helix interaction shown in the structure of a protamine-transfer RNA complex and a nucleoprotamine model.

Single crystal X-ray diffraction and circular dichroism studies of protamine binding to a tRNA suggest that the protamine molecule changes its conformation from a random coil to a structure containing a helices on binding to tRNA, and that alpha-helical segment(s) of protamine bind approximately along a shallow groove of a double-helical portion of ttrna. based on these observations, a structural model for nucleoprotamine is proposed.

Amino Acid Sequence↗

The effects of protamine on a murine leukemia virus.

THIS STUDY INDICATED THAT: (1) i.p. inoculation of protamine into (Rauscher) leukemic mice increased their X death time, (2) protamine was more toxic for leukemic than normal mice and (3) the in vitro reaction between Rauscher virus and protamine reduced its infectivity for mice.

Animals↗

Biospecific affinity chromatography of an adenosine 3':5'-cyclic monophosphate-stimulated protein kinase (protamine kinase from trout testis) by using immobilized adenine nucleotides.

1. Two adenine nucleotides, 8-(6-aminohexyl)aminoadenosine 3':5'-cyclic monophosphate and 8-(6-aminohexyl)amino-AMP, were synthesized. Their structures were established in particular by using mass spectroscopy. 2. Free cyclic AMP and 8-(6-aminohexyl)amino cyclic AMP both stimulate protamine kinase activity at low concentrations, but are inhibitory at concentrations above 0.1mm. AMP is an inhibitor of enzymic activity, whereas neither 8-(6-aminohexyl)amino-AMP nor the earlier synthesized N(6)-(6-aminohexyl)-AMP is inhibitory. 3. The nucleotides were coupled to Sepharose 4B and used for biospecific chromatography of partially purified protamine kinase. Enzyme applied at high buffer concentrations to the cyclic AMP-Sepharose material was retarded and thereby purified tenfold. At low buffer concentrations the enzyme was adsorbed to the affinity material, and was subsequently released by a pulse of the inhibitor AMP, yielding a 50-100-fold purification. Enzyme applied to immobilized 8-(6-aminohexyl)amino-AMP or N(6)-(6-aminohexyl)-AMP was eluted together with the main protein peak in the void volume. 4. Protamine kinase eluted from 8-(6-aminohexyl)amino cyclic AMP-Sepharose was no longer activated by cyclic AMP. Results from sucrose gradient centrifugation suggest that a dissociation of the enzyme took place on the immobilized nucleotide. 5. Further information on the mass spectroscopy has been deposited as Supplementary Publication SUP 50026 at the British Library (Lending Division) (formerly the National Lending Library for Science and Technology), Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies may be obtained on the terms given in Biochem. J. (1973) 131, 5.

Adenine Nucleotides↗

Life threatening cardiopulmonary failure in an infant following protamine reversal of heparin after cardiopulmonary bypass.

Life threatening cardiopulmonary failure following protamine reversal of heparin after cardiopulmonary bypass (CPB) was reported to occur in adults but rarely in children. Atrial septal defect closure was performed in a 6-week-old infant erroneously suspected to suffer from right atrial thrombosis in addition. Protamine administration after CPB led to critical pulmonary hypertension and severe haemorrhagic pulmonary oedema resulting in severe hypoxia. Inhaled nitric oxide, together with high frequency oscillation ventilation supplemented by intravenous prostacycline, enabled complete recovery of cardiopulmonary and neurological function. Life threatening cardiovascular compromise after intravenous protamine can occur even in young infants which then require challenging paediatric critical care.

Cardiopulmonary Bypass↗

Protamines of reptiles.

We have characterized for the first time the complete primary structure of the main protamine components of the sperm from four reptiles: Chrysemys picta (turtle), Elaphe obsoleta (snake), Anolis carolinensis (lizard), and Alligator mississipiensis (crocodilian). These species were chosen to represent one of each of the main phylogenetic branches of this taxonomic group. Comparison of these protamine sequences with those already available from other vertebrate groups allows us to define properly the chemical consensus composition of protamines and provides a unique insight into their molecular evolution and classification.

Alligators and Crocodiles↗

Nuclear matrix interactions at the human protamine domain: a working model of potentiation.

The compact eukaryotic genome must be selectively opened to grant trans-factor access to cis-regulatory elements to overcome the primary barrier to gene transcription. The mechanism that governs the selective opening of chromatin domains (i.e. potentiation) remains poorly understood. In the absence of a well defined locus control region, the nuclear matrix is considered the primary candidate regulating the opening of the multigenic PRM1 --> PRM2 --> TNP2 human protamine domain. To directly examine its role, four lines of transgenic mice with different configurations of flanking nuclear matrix attachment regions (MARs) encompassing the protamine domain were created. We show that upon removal of the MARs, the locus becomes subject to position effects. The 3' MAR alone may be sufficient to protect against silencing. In concert, the MARs bounding this domain likely synergize to regulate the expression of the various members of this gene cluster. Interestingly, the MARs may convey a selective reproductive advantage, such that constructs bearing both 5' and 3' MARs are passed to their offspring with greater frequency. Thus, the MARs bounding the PRM1 --> PRM2 --> TNP2 protamine domain have many and varied functions.

Animals↗

Interaction of polyadenylic acid (5') with histone H1 or protamine.

The interaction between polyadenylic acid (5') (poly [A]) and histone (or protamine) was analyzed by electrophoretic retardation of poly [A]-histone (or protamine) complex in agarose gel. The potency of interaction was protamine > histone H1, arginine-rich histone > other histones. The catalytic subunit of cyclic AMP-dependent protein kinase effectively decreased the electrophoretic retardation of poly [A]-histone H1. The interaction between poly [A] and histone H1 was also detected by the drastically enhanced absorbance around 340 nm. The findings may implicate a regulatory role of histone H1 on mRNAs through its binding on poly [A] tails.

Calmodulin↗

Involvement of an acrosinlike proteinase in the sulfhydryl-induced degradation of rabbit sperm nuclear protamine.

Previous studies demonstrated that proteolytic activity is associated with isolated rabbit sperm nuclei and is responsible for the degradation of nuclear protamine that occurs during thiol-induced in vitro decondensation of the nuclei (Zirkin and Chang, 1977; Chang and Zirkin, 1978). In this study, we present the results of experiments designed to characterize this proteolytic activity. Basic protein isolated from rabbit sperm nuclei incubated with 5 mM dithiothreitol (DTT) and 1 percent Triton X-100 for increasing periods of time exhibited progressively faster migrating bands on acid-urea polyacrylamide gels, reflection the progressive degradation of protamine. Ultimately, a specific and characteristic peptide banding pattern resulted. When sperm nuclei were treated with the esterase inhibitor nitrophenyl-p-guanidino benzoate (NPGB) to inhibit the nuclear-associated proteolytic activity and then incubated with one of several exogenous proteinases in addition to DTT and Triton X-100, characteristic peptide banding patterns were seen for each exogenous proteinase employed. For trypsin, chymotrypsin, pronase, and papain, the peptide banding patterns differed from one another and from the pattern characteristic of protamine degradation by the nuclear-associated proteinase. By contrast, when rabbit acrosin served as the exogenous proteinase, the peptide banding pattern seen was identical to the pattern characteristic of the nuclear-associated proteinase. These results demonstrate directly that the proteinase associated with rabbit sperm nuclei and involved in sperm nuclear decondensation in vitro is acrosinlike.

Acrosin↗

Interactions of C-reactive protein with the complement system. I. Protamine-induced consumption of complement in acute phase sera.

Protamine sulfate was found to consume large amounts of C selectively during preincubation with sera of individuals in the "acute phase". Marked depletion of C1, C4, and C2 with minimal, if any, depletion of C3-9, was observed. The consumption was time and temperature dependent, occurring most rapidly and extensively at 37 degrees C, 0.10 M relative salt concentration and pH 7.5-8.0; it required calcium ions. It was mediated by a heat-stable nondialyzable factor which separated with C-reactive protein (CRP) during fractionation and purification, correlated with serum CRP levels, and, like other known reactivities of CRP, was inhibited by phosphoryl choline. Preparations of CRP purified either from serum or ascites resulted in consumption of large amounts of C1, C4, and C2 when preincubated with normal serum and protamine. We conclude that CRP is a potent activator of the C system at the level of C1, and that polycations such as protamine sulfate are substrates of CRP which can bring about this activation. It seems not unlikely that one role of CRP in health and disease involves its ability to interact with the C system.

Animals↗

Detection of fibrin monomer. Comparison of the immune precipitate method with the serial-dilution protamine sulfate test and the ethanol gel test.

In a previous publication, a method for measuring fibrin monomer in plasma with the use of an immune precipitate of fibrinogen was described. The method was found to be more sensitive to unstabilized fibrin monomer than the serial-dilution protamine sulfate test, or the ethanol gel test, and detected fibrin in a mixture of the plasmin digestion products of fibrin. In the present study the sensitivity of the immune precipitate method for detecting specific plasmin digestion products of fibrin X, Y, D, and E, its sensitivity for stabilized fibrin monomer complexes, and its sensitivity for fibrin retaining B-peptide were measured and compared with the corresponding sensitivities of the serial-dilution protamine sulfate test and the ethanol gel test for detecting these same products. The immune precipitate method was found to be highly sensitive to stabilized fibrin monomer complexes and to fibrin retaining B-peptide; to be significantly less sensitive to the plasmin digestion fragments X, Y, and E; and to be insensitive to fragment D. The serial-dilution protamine sulfate test and the ethanol gel test were found to be insensitive to all of the plasmin digestion products of fibrin and less sensitive to the other fibrin complexes.

Batroxobin↗

Complement activation during cardiopulmonary bypass by heparin-protamine interaction.

Circulating concentrations of split products of the third complement factor (C3c and C3d) were measured in five patients before, during and after cardiopulmonary bypass. In all patients, C3d concentrations increased significantly in samples obtained after the administration of protamine sulphate. Similarly, circulating C3c was seen only in those samples obtained immediately after protamine administration. In vitro experiments demonstrated that activation of the complement system was attributable to the heparin-protamine complex, and was dose-dependent. The activation of complement was not associated with any clinically detectable adverse effects.

Adult↗

Effects of Ni(II) and Cu(II) on DNA interaction with the N-terminal sequence of human protamine P2: enhancement of binding and mediation of oxidative DNA strand scission and base damage.

Epidemiological evidence suggests that certain paternal exposures to metals may increase the risk of cancer in the progeny. This effect may be associated with promutagenic damage to the sperm DNA. The latter is packed with protamines which might sequester carcinogenic metals and moderate the damage. Human protamine P2 has an amino acid motif at its N-terminus that can serve as a heavy metal trap, especially for Ni(II) and Cu(II). We have synthesized a pentadecapeptide modeling this motif, Arg-Thr-His-Gly-Gln-Ser-His-Tyr-Arg-Arg-Arg-His-Cys-Ser-Arg-amide (HP21-15) and described its complexes with Ni(II) and Cu(II), including their capacity to mediate oxidative DNA degradation [Bal et al. (1997) Chem. Res. Toxicol., 10, 906-914 and 915-921]. In the present study, effects of HP21-15 on Ni(II)- and Cu(II)-mediated DNA oxidation by H2O2 at pH 7.4 were investigated in more detail using the circular plasmid pUC19 DNA as a target, and the single/double-strand breaks and production of oxidized DNA bases, as end points. Ni(II) alone was found to promote oxidative DNA strand scission (mostly single strand breaks) and base damage, while Cu(II) alone produced the same effects, but to a much greater extent. Both metals were relatively more damaging to the pyrimidine bases than to purine bases. HP21-15 tended to increase the Ni(II)/H2O2-induced DNA breakage. In sharp contrast, the destruction of DNA strands by Cu(II)/H2O2 was almost completely prevented by HP21-15. The effect of HP21-15 on the oxidative DNA base damage varied from a limited enhancement (5-hydroxyhydantoin and thymine glycol) to slight suppression (5-hydroxycytosine, 5-hydroxyuracil, 8-oxoguanine, 8-oxoadenine, 2-hydroxyadenine, fapyguanine and fapyadenine) toward Ni(II)/H2O2. HP21-15 strongly suppressed the oxidative activity of Cu(II)/H2O2 in regard to all bases in DNA. Consistently with the above, the electron spin resonance/spin trap measurements revealed greater and more persistent generation of OH* and O2-*-like oxidants from H2O2 by the Ni(II)-HP21-15 complex than by the Cu(II)-HP21-15 complex (no O2-* was detected). Both complexes were also found to bind to DNA more strongly than HP21-15 alone. The results indicate that protamine P2 is capable of binding Ni(II) and Cu(II) and, in this way, attenuating the mediation of oxidative DNA damage by Cu(II), but not Ni(II). The effects found may be mechanistically involved in the reproductive toxicity and carcinogenicity of metals.

Animals↗