NOTES
Reticuloendothelial system blockade-induced humoral factor depletion and susceptibility to hemorrhagic shock'
Can. J. Physiol. Pharmacol. Downloaded from www.nrcresearchpress.com by University of Waterloo on 01/08/15 For personal use only.
DANIELJ. LOEGERHNG AND R~ARLOWE J. SCHNEIDKRAUT Department of Phsiology, Albany medical College, Albany, N Y , I1.S.A. 62208 Received June 23, 1978 LOEGERING, D. J., and SCHMEIDKRAUT', hl. J. 1978. Reticuloendothelial system blockadeinduced humoral factor depletion and susceptibility to hemorrhagic shock. Can. J . Physiol. Pharmacol. 56, 1055-1053. This study was carried out to determine if reticuloendothelial system (RES) blockadeinduced depletion of circulating alpha-2-glycoprotein opsonic activity resulted in increased susceptibility to hemorrhagic shock. RES blockade induced by the injection s f gelatinized lipid emulsion was associated with a 45.9% decrease in phagocytic index and a 85-3% decrease in plasma alpha-2-glycoprotein opsonic activity. Animals subjected to RES blockade 30 min prior to hemorrhagic shock showed a decrease in time to decompensation and a decrease in maximum shed volume. These results are consistent with the concept that circulating levels of this opsonic protein are important in modulating RES phagocytic function and in host defense to shock. LOEGERING, D. J., et S C I ~ N E ~ K R AM. U TJ., 1978. Reticuloendothe%ialsystem klockadeinduced hun~oralfactor depletion and susceptibility to hemol-rhagic shock. Can. J . Physiol. Pharmacol. 56, 1055-1057. On :t men6 cette ttude afin de diterminer si 19Cpuisernentde 19activit6 opsonique de 19alph:a-2-glycoprotieine circulante suite B un blocage provoquC du sy~tkrnerkticuloendothtlial (KES), rCsulte en une sensibilitt accrue au choc hkmorragique. On associe le blocage RES risultant de l'iiajection d'une 6mulsion de lipides gklatineux, 21 a~nerkduction de 45.9y0 de I'image d'Arneth (index phagocytique) et une diminution de 85.3y0 de I'activitt opsonique de I'alpha-2-glycoproteine plasmatique. Les animaux soumis au blocage RES 30 min avant le choc hCmorragique montrent une diminr~tiondu temps de dicompensation et tgaIement une diminution du volume maximum perdu. Ces rtsuitats appuient le principe selon lequel les niveaux de cette prothine spsonique en circulation aurait un r61e B loner dans la modulation de la fonction RES phagscytique et darns la dkfense de 1'hGte contre l'htn~orragie. [Traduit par le journal]
Introduction Several studies have implicated the involvement of a humoral opsonic factor in tlle reticuloendothelial system (RES) depression associated with various forms of injury and shack (Saba and Scovill 1975; Kaplan and Saba 1976; Schildt 1976; Loegering 1977) as well as with RES colloidal blockade (Saba and DiLuzio 1969; Blumenstock et al. 1977). This opsonic factor has been isolated and characterized as an alplma-2-glycoprotein and has recently been referred to as "alpha-2-surface binding glycoprotein" (Blumenstock et al. 1976; Blurnenstock et al. 1978). Since the circulating levels of this protein are depressed during shock states which are associated with RES depression it has been proposed that this protein may mediate the depression of RES phagocytic function during shock (Saba 1975: Kaplan and Saba 1976; Sshildt 1976; Loegering 1977). In sup'This study was supported by United States Public Health Service grant HL- 18051.
port sf this proposal it has been shown that the passive provision of purified opsonic alpha-2-glycoprotein prevented the RES depression associated with surgical injury (Saba et al. 1977) and that the depletion of this protein from the circulation following antibody injection resulted in depression of RES function and increased susceptibility to experimerltal traumatic shock (Kaplan, Saba et al. 1976). The present study was carried out to deternmine if RES blockade-induced depletion of this opsonic protein from the circulation prior to hemorrhagic shock results in increased susceptibility to this form of shock.
Methods Male Spragaae-Dawley rats weighing 250-300 g were used in all experiments. Animals were anesthetized with sodium pentobarbital (30 mgikg, iv); a femoral artery was cannulated and colonic temperature was monitored and maintained at 36-37°C. WES blockade was induced by the intravenous injection of unlabeled gelatinized lipid emulsion (50 mg/ 100 g ) .
1056
CAN. J. PHYSIOL. PHARMACOL. VOL. 56, 1978
TABLE 1. Organ localization of the test colloid after RES blockade
Can. J. Physiol. Pharmacol. Downloaded from www.nrcresearchpress.com by University of Waterloo on 01/08/15 For personal use only.
Control Blockade
Liver
Spleen
Lungs
40.40i1.16a 22.73k2.03b
3.73k0.22 5.62k0.81b
1.335-0.05 1 .54+0.08b
aData represent the percent injected dose of 13LI-labeledgelatinized lipid emulsion per total organ. Values are expressed as mean and standard error of the mean with six animals per group. bp < 0.05.
-
-
changes in mean arterial blood pressure for the 30rnin observation period following injection of the FIG. 1. Phagocytic index and plasma alpha-2-glycoprotein gelatinized lipid emulsion. opsonic activity determined 30 rnin after the injection of Animals blockaded with gelatinized lipid emulgelatinized lipid emulsion (50 mg/ 100 g) or an equal volume sion showed a 23.1 % decrease ( p < 0.01) in time of diluent (control). The values are different at p < 0.001. The values are expressed as mean and standard error of the to initial decompensation and a 19.6% reduction mean of six animals per group. ( p < 0.05) in maximum shed volume (Fig. 2 ) . These changes were interpreted as indicating an inThirty minutes after injection phagocytic index was detercreased susceptibility to hemorrhagic shock. mined, plasma alpha-2-glycoprotein opsonic activity was deCONTROL
BLOCKADE
termined or hemorrhagic shock was initiated. Control animals received an injection of an equal volume (0.5 ml/ 100 g) of the emulsion dilutent (5% dextrose in water). Phagocytic index was determined from the clearance rate of '"'I-labeled gelatinized emulsion as previously described (Saba and DiLuzio 1969; Loegering 1977). The injected dose of the emulsion was 50 mg/100 g and immediately after the 10-min clearance test the liver, spleen, and lungs were removed and the '"I content of the organs determined. Plasma alpha-2-glycoprotein opsonic activity was determined using the liver slice bioassay (Saba and DiLuzio 1969; Loegering 1977). Plasma opsonic activity was expressed as the percent of the added colloid phagocytized per 100 mg of hepatic tissue (96ID/ 100 mg). Hemorrhagic shock was induced as previously described (Loegering and Carr 1977) by withdrawing sufficient blood to decrease the mean arterial blood pressure to 40 mmHg within 10 min. The arterial blood pressure was then maintained at 40-45 mmHg by withdrawing small volumes of blood until the point of initial decompensation, that is, when it was first necessary to return some of the withdrawn blood to maintain blood pressure. Shock susceptibility was evaluated on the basis of the duration of hypotension required to reach the point of initial decompensation and the maximum shed volume. Data were analyzed using the Student's t-test with a confidence interval for significance set at 95%. Data are expressed as the mean and standard error of the mean.
Results The injection of 5 0 mg/ 100 g of gelatinized lipid emulsion to induce RES blockade resulted in a 45.9% decrease in phagocytic index 30 min after injection (Fig. 1 ) . This depression in phagocytic index was associated with a substantial reduction in hepatic localization of the test colloid and an increase in colloid localization in the spleen and lungs (Table 1 ) . Bioassayable plasma alpha-2-glycoprotein opsonic activity was decreased 85.7% 30 rnin after colloid injection (Fig. I ) . There were no
Discussion Depression of RES phagocytic function by RES colloidal blockade has been shown to increase the susceptibility to various forms of shock (Zweifach et al. 1957; Fine et al. 1959; Filkins et al. 1964; Altura and Hershey 14 ;1). These studies form part of the basis for implicating RES depression in the pathogenesis of irreversible shock. Since the RES is normally involved in the clearance from the blood of altered and foreign material such as damaged erythrocytes (Rifkind 1966), erythrocyte debris (Schneidkraut and Loegering 1978), products of coagulation (Walsh and Barnhart 1969; Lee and McClusky 1962), and bacterial endotoxin (Buchanan and Filkins 1976) it has been proposed that
1 TROL
CON
FIG. 2. Effect of RES blockade on time to initial decompensation and maximum shed volume during hemorrhagic shock. Hemorrhage was initiated 30 rnin after RES blockade induction. Significant differences in time to decompensation ( p 0.05) and in maximum shed volume (p 0.01) were observed. Values are expressed as the mean and standard error o r the mean of 11 animals per group.
Reticuloendothelial system blockade-induced humoral factor depletion and susceptibility to hemorrhagic shock'
Can. J. Physiol. Pharmacol. Downloaded from www.nrcresearchpress.com by University of Waterloo on 01/08/15 For personal use only.
DANIELJ. LOEGERHNG AND R~ARLOWE J. SCHNEIDKRAUT Department of Phsiology, Albany medical College, Albany, N Y , I1.S.A. 62208 Received June 23, 1978 LOEGERING, D. J., and SCHMEIDKRAUT', hl. J. 1978. Reticuloendothelial system blockadeinduced humoral factor depletion and susceptibility to hemorrhagic shock. Can. J . Physiol. Pharmacol. 56, 1055-1053. This study was carried out to determine if reticuloendothelial system (RES) blockadeinduced depletion of circulating alpha-2-glycoprotein opsonic activity resulted in increased susceptibility to hemorrhagic shock. RES blockade induced by the injection s f gelatinized lipid emulsion was associated with a 45.9% decrease in phagocytic index and a 85-3% decrease in plasma alpha-2-glycoprotein opsonic activity. Animals subjected to RES blockade 30 min prior to hemorrhagic shock showed a decrease in time to decompensation and a decrease in maximum shed volume. These results are consistent with the concept that circulating levels of this opsonic protein are important in modulating RES phagocytic function and in host defense to shock. LOEGERING, D. J., et S C I ~ N E ~ K R AM. U TJ., 1978. Reticuloendothe%ialsystem klockadeinduced hun~oralfactor depletion and susceptibility to hemol-rhagic shock. Can. J . Physiol. Pharmacol. 56, 1055-1057. On :t men6 cette ttude afin de diterminer si 19Cpuisernentde 19activit6 opsonique de 19alph:a-2-glycoprotieine circulante suite B un blocage provoquC du sy~tkrnerkticuloendothtlial (KES), rCsulte en une sensibilitt accrue au choc hkmorragique. On associe le blocage RES risultant de l'iiajection d'une 6mulsion de lipides gklatineux, 21 a~nerkduction de 45.9y0 de I'image d'Arneth (index phagocytique) et une diminution de 85.3y0 de I'activitt opsonique de I'alpha-2-glycoproteine plasmatique. Les animaux soumis au blocage RES 30 min avant le choc hCmorragique montrent une diminr~tiondu temps de dicompensation et tgaIement une diminution du volume maximum perdu. Ces rtsuitats appuient le principe selon lequel les niveaux de cette prothine spsonique en circulation aurait un r61e B loner dans la modulation de la fonction RES phagscytique et darns la dkfense de 1'hGte contre l'htn~orragie. [Traduit par le journal]
Introduction Several studies have implicated the involvement of a humoral opsonic factor in tlle reticuloendothelial system (RES) depression associated with various forms of injury and shack (Saba and Scovill 1975; Kaplan and Saba 1976; Schildt 1976; Loegering 1977) as well as with RES colloidal blockade (Saba and DiLuzio 1969; Blumenstock et al. 1977). This opsonic factor has been isolated and characterized as an alplma-2-glycoprotein and has recently been referred to as "alpha-2-surface binding glycoprotein" (Blumenstock et al. 1976; Blurnenstock et al. 1978). Since the circulating levels of this protein are depressed during shock states which are associated with RES depression it has been proposed that this protein may mediate the depression of RES phagocytic function during shock (Saba 1975: Kaplan and Saba 1976; Sshildt 1976; Loegering 1977). In sup'This study was supported by United States Public Health Service grant HL- 18051.
port sf this proposal it has been shown that the passive provision of purified opsonic alpha-2-glycoprotein prevented the RES depression associated with surgical injury (Saba et al. 1977) and that the depletion of this protein from the circulation following antibody injection resulted in depression of RES function and increased susceptibility to experimerltal traumatic shock (Kaplan, Saba et al. 1976). The present study was carried out to deternmine if RES blockade-induced depletion of this opsonic protein from the circulation prior to hemorrhagic shock results in increased susceptibility to this form of shock.
Methods Male Spragaae-Dawley rats weighing 250-300 g were used in all experiments. Animals were anesthetized with sodium pentobarbital (30 mgikg, iv); a femoral artery was cannulated and colonic temperature was monitored and maintained at 36-37°C. WES blockade was induced by the intravenous injection of unlabeled gelatinized lipid emulsion (50 mg/ 100 g ) .
1056
CAN. J. PHYSIOL. PHARMACOL. VOL. 56, 1978
TABLE 1. Organ localization of the test colloid after RES blockade
Can. J. Physiol. Pharmacol. Downloaded from www.nrcresearchpress.com by University of Waterloo on 01/08/15 For personal use only.
Control Blockade
Liver
Spleen
Lungs
40.40i1.16a 22.73k2.03b
3.73k0.22 5.62k0.81b
1.335-0.05 1 .54+0.08b
aData represent the percent injected dose of 13LI-labeledgelatinized lipid emulsion per total organ. Values are expressed as mean and standard error of the mean with six animals per group. bp < 0.05.
-
-
changes in mean arterial blood pressure for the 30rnin observation period following injection of the FIG. 1. Phagocytic index and plasma alpha-2-glycoprotein gelatinized lipid emulsion. opsonic activity determined 30 rnin after the injection of Animals blockaded with gelatinized lipid emulgelatinized lipid emulsion (50 mg/ 100 g) or an equal volume sion showed a 23.1 % decrease ( p < 0.01) in time of diluent (control). The values are different at p < 0.001. The values are expressed as mean and standard error of the to initial decompensation and a 19.6% reduction mean of six animals per group. ( p < 0.05) in maximum shed volume (Fig. 2 ) . These changes were interpreted as indicating an inThirty minutes after injection phagocytic index was detercreased susceptibility to hemorrhagic shock. mined, plasma alpha-2-glycoprotein opsonic activity was deCONTROL
BLOCKADE
termined or hemorrhagic shock was initiated. Control animals received an injection of an equal volume (0.5 ml/ 100 g) of the emulsion dilutent (5% dextrose in water). Phagocytic index was determined from the clearance rate of '"'I-labeled gelatinized emulsion as previously described (Saba and DiLuzio 1969; Loegering 1977). The injected dose of the emulsion was 50 mg/100 g and immediately after the 10-min clearance test the liver, spleen, and lungs were removed and the '"I content of the organs determined. Plasma alpha-2-glycoprotein opsonic activity was determined using the liver slice bioassay (Saba and DiLuzio 1969; Loegering 1977). Plasma opsonic activity was expressed as the percent of the added colloid phagocytized per 100 mg of hepatic tissue (96ID/ 100 mg). Hemorrhagic shock was induced as previously described (Loegering and Carr 1977) by withdrawing sufficient blood to decrease the mean arterial blood pressure to 40 mmHg within 10 min. The arterial blood pressure was then maintained at 40-45 mmHg by withdrawing small volumes of blood until the point of initial decompensation, that is, when it was first necessary to return some of the withdrawn blood to maintain blood pressure. Shock susceptibility was evaluated on the basis of the duration of hypotension required to reach the point of initial decompensation and the maximum shed volume. Data were analyzed using the Student's t-test with a confidence interval for significance set at 95%. Data are expressed as the mean and standard error of the mean.
Results The injection of 5 0 mg/ 100 g of gelatinized lipid emulsion to induce RES blockade resulted in a 45.9% decrease in phagocytic index 30 min after injection (Fig. 1 ) . This depression in phagocytic index was associated with a substantial reduction in hepatic localization of the test colloid and an increase in colloid localization in the spleen and lungs (Table 1 ) . Bioassayable plasma alpha-2-glycoprotein opsonic activity was decreased 85.7% 30 rnin after colloid injection (Fig. I ) . There were no
Discussion Depression of RES phagocytic function by RES colloidal blockade has been shown to increase the susceptibility to various forms of shock (Zweifach et al. 1957; Fine et al. 1959; Filkins et al. 1964; Altura and Hershey 14 ;1). These studies form part of the basis for implicating RES depression in the pathogenesis of irreversible shock. Since the RES is normally involved in the clearance from the blood of altered and foreign material such as damaged erythrocytes (Rifkind 1966), erythrocyte debris (Schneidkraut and Loegering 1978), products of coagulation (Walsh and Barnhart 1969; Lee and McClusky 1962), and bacterial endotoxin (Buchanan and Filkins 1976) it has been proposed that
1 TROL
CON
FIG. 2. Effect of RES blockade on time to initial decompensation and maximum shed volume during hemorrhagic shock. Hemorrhage was initiated 30 rnin after RES blockade induction. Significant differences in time to decompensation ( p 0.05) and in maximum shed volume (p 0.01) were observed. Values are expressed as the mean and standard error o r the mean of 11 animals per group.
