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The levels of isohemagglutinins, isohemolysins, heterohemagglutinins and lysozyme in blood serum of one and half year old carps have been fixed after scales transplantation. Since three weeks after grafting isohemagglutinins and isohemolysins were revealed in recipient fishes with the prevalence of 25% and 95% respectively. Intact carps from the same group were lack of these antibodies. Recipient and intact fishes did not differ reliably by heterohemagglutinins and lysozyme level in the blood serum. There was no correlation between destroyed allografts share and hemolysins titre of serum, so the double role of humoral antibodies in grafting immunity in carps can be assumed.  相似文献   

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A "bolus" dose (110 microgram) of the angiotesin II (A II)-blocker 1-Sar-8-Ala-A II (Saralasin, S) followed by its slow rate infusion (5 microgram/min/rat) for thirty min, was injected before and after the complete ganglionic blockade by pentolinium (P) in unanaesthetized unilaterally clipped renal hypertensive rats (the opposite kidney remained untouched). Pentolinium was also injected like a "bolus" dose (3 mg) followed by slow infusion (0.1 mg/min/rat) for thirty min. The observations were made until the fifth week after clipping the left renal artery. A consistent maximal hypotensive response was observed after the "bolus test" with both drugs. When S was the first drug injected, an inverse correlation was found between the percent decrease in arterial pressure (BP) by S and the percent decrease in BP by P (r = --0.83, P < 0.01, n = 8). Thus whenever a greater hypotensive effect was obtained by S, a smaller neural pressor component remained to be blocked by P. On the other hand, when P was the first drug injected a lesser A II pressor component remained to be blocked by S in the hypertensive rats. The results suggest that a considerable A II pressor effect in two-kidney renovascular hypertension is mediated via neurogenic mechanisms from the first week. A direct pressor vasoconstriction was found to be significant in cases with very high plasma-renin activity.  相似文献   

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1. Preliminary, general chemical characteristics of substances in artificial sea water (ASW) washed through stimulated body wall (SBW) and in hemolymph taken from noxiously stimulated animals (SHL) were consistent with those of classical neurotransmitters, amino acids, and small- to medium-sized peptides. 2. 5-Hydroxytryptamine (5HT) and acetylcholine (ACh), unlike SBW and SHL, caused relaxation when perfused into isolated body wall. FMRFamide produced a biphasic response--brief contraction followed by prolonged relaxation. 3. Small cardioactive peptide (SCPB) caused body wall contractions similar to those produced by SBW and SHL, except that SCPB contractions displayed more desensitization and were completely blocked by 30 mM CoCl2. SCPB and SBW contractions were synergistic. 4. Dopamine caused persistent body wall contractions similar to those of SBW and SHL. Dopamine contractions were reduced but not blocked by 30 mM CoCl2. Unlike SBW activity, dopamine activity was reduced by alkalinization. 5. Glutamate and taurine produced strong but usually short-lasting body wall contractions. Adenosine, octopamine, arginine vasotocin, and cholecystokinin (CCK-8) caused weak or variable contractions. Met-enkephalin and somatostatin caused no obvious body wall responses. 6. When superfused over the fully sheathed abdominal ganglion, FMRFamide, met-enkephalin, glutamate, aspartate, and taurine reduced the magnitude of the gill-withdrawal reflex elicited by siphon nerve stimulation. 7. Taken together with earlier results, these data suggest a preliminary framework for trauma signal pathways. It is proposed that stress hormones (perhaps including FMRFamide, SCPs, 5HT, and dopamine) are released into hemolymph from neuroendocrine cells. Effective amounts of active intracellular solutes such as amino acids may also be released by extensive cellular rupture. Various humoral signals produce slow effects that contribute to hemostasis, balling up, increased cardiac output, and reflex suppression.  相似文献   

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1. Mechanical or electrical stimulation of isolated sections of body wall produced contractions that were graded with the intensity of the stimulus. Injury of body wall with shallow incisions produced extremely persistent contractions. 2. Long-lasting contraction of isolated body wall was also produced by brief application of "stimulated body wall wash" (SBW), sea water which was first washed through another section of body wall subjected to intense mechanical or electrical stimulation. Contractions were produced by SBW diluted to concentrations as low as 1% of the initial concentration. Contractions produced by prolonged application of SBW showed little fatigue, tachyphylaxis, or desensitization. 3. SBW caused contraction of isolated sections of body wall from all regions of the body, including tail, parapodia, siphon, purple gland, rhinophores, and anterior tentacles. SBW also caused contraction of isolated lateral columellar muscle and of the gill. 4. 30 mM CoCl2 blocked the release of contractile factors into electrically stimulated body wall and reduced but did not abolish contractile responses of unstimulated body wall to perfused SBW. SBW contractions were unchanged by disconnection of the perfused tissue to the CNS. 5. Hemolymph collected from the neck of an intact donor following strong electrical stimulation of the tail or excision of a parapodium ('stimulated hemolymphh, SHL) caused long-lasting contractions which were larger than those produced by control hemolymph (CHL) collected prior to stimulation of the donor. 6. Similarities between body wall contractions produced by SHL and by SBW, including their occurrence in 30 mM CoCl2, suggest that some of the contractile activity in SHL may be directly released from traumatized body wall. 7. SHL caused significantly greater cardioacceleration of the isolated heart than did CHL. Similarities between the cardioacceleration produced by SHL and by SBW suggest that a source of cardiac activity in SHL may be traumatized body wall. 8. SBW suppressed the gill-withdrawal reflex when applied selectively to the sheathed or desheathed abdominal ganglion. SBW-induced suppression was associated with significant reduction of evoked spike activity in identified gill motor neurons. SHL collected 1-2 h after noxious stimulation caused weak but significant suppression of the gill-withdrawal reflex when applied to the fully sheathed abdominal ganglion.  相似文献   

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Humoral defence factors in Indian river prawn, Macrobrachium malcolmsonii   总被引:1,自引:0,他引:1  
A preliminary study on humoral defence factors of Indian river prawn, Macrobrachium malcolmsonii was carried out. The serum of animals collected from intermoult stage had an average total protein content of 9.65 g dl(-1) and lysozyme-like activity of 0.04 unit ml(-1). The phenoloxidase activity in haemocyte lysate supernatant was triggered significantly (P < 0.05) by chitosan, Gram-positive and Gram-negative bacterial cells in comparison to other elicitors viz., levamisole, trypsin and glucan. The serum contained an agglutinin against Gram-negative bacteria and a haemagglutinin against a wide range of vertebrate erythrocytes. The haemagglutinin was stable over a wide range of pH (3.0-7.0) and temperatures (-30 degrees C to 60 degrees C). A 413 kDa N-acetyl galactosamine-specific haemagglutinin was purified by single step affinity chromatography and the protein was found to be calcium ion-dependent in nature and made up of five different subunits of varied molecular weights on denaturing SDS-PAGE.  相似文献   

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The facts known today about the occurrence and possible mechanisms of anaemias caused by medicaments are represented in a survey. In this connection toxic haemolytic anaemias, immunohaemolytic anaemias, toxic aplastic anaemias, megaloblastic anaemias, and some other, more rarely occurring types are referred to.  相似文献   

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Bioassay studies in the old and recent literature suggest the presence of an unknown slowly acting pressor agent in the blood of animals and man with volume expanded (low renin) hypertension. Recent studies in our laboratories suggest that the sodium-potassium pump activity of blood vessels is suppressed in animals with one-kidney, one wrapped, one-kidney, one clip, and one-kidney, DOCA, salt hypertension. Similar reduction of Na+, K+-ATPase activity has been observed in the left ventricle of animals with one-kidney, one clip and one-kidney, DOCA salt hypertension. The changes do not appear to result from increased pressure since they have also been observed in veins and right ventricle. Acute volume expansion of the normal rat with saline suppresses pump activity in the tail artery and plasma from these animals suppresses pump activity when applied to a tail artery from another rat. Data in the literature indicate that the adrenergic nerve terminals are depleted of norepinephrine. Suppression of pump activity, with ouabain for example, is known to activate cardiovascular muscle and reduce norepinephrine uptake by nerve terminals. These observations suggest a role for a slowly acting ouabain-like humoral agent, which acts directly on cardiovascular muscle to increase contractility and on nerve endings to reduce reflex compensation, in the genesis of volume expanded hypertension.  相似文献   

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The frequency of chromosome aberrations in bone-marrow cells of mice in tissue incompatibility conflicts, and in the lymphocytes of the peripheral blood of 20 patients suffering from different allergies was studied. It was established that in mice, during allograft rejection, i.e. on the 10th–15th days after grafting of allogeneic skin, the frequency of cells with chromosome aberrations increases significantly up to 12–15% against 4–5% in the control. On the 20th day after grafting, the level of chromosome aberrations falls back to the control level. In allergic patients the frequency of cells with chromosome aberrations was 10.7% (4–22%). In numerous control subjects this value did not exceed 2%. The highest level of aberrations was found during the acute stage of the disease especially in patients in the state of anaphylactic shock. No correlation was found between the frequency of aberrant cells and the action of definite allergens. The problem of the possibility of extending the above described phenomenon to non-immunocompetent cells of mammals, and of the role of immunological stress in spontaneous mutagenesis are discussed.  相似文献   

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