Toxiroa, Vol. 16, pp. 343-330. ^,ç Perpmon Pros Ltd. 1978. Printed in Crreat rritnin .
0041-0101178/1101-0343f02.00/0
EFFECTS OF STAPHYLOCOCCAL ENTEROTOXIN B ON FUNCTIONAL AND BIOCHEMICAL CHANGES OF THE LUNG IN RHESUS MONKEYS* C. T. Lnr, R. D. DeLAUrER, M. J . Gwr'FIN and C. L. HADICIc U.S . Army Medical Research Institute of Infectious Diseases, Fort Derrick, Frederick, Maryland 21701, U.S.A . (Acceptedjor publication 13 March 1978) C. T. Ltv, R. D. DEI,wrEa, M. J. GRIFFIN and C. L. H~ntctc. Efforts of staphylococcal cnterotoxin B on functional and biochemical changes of the lung in rhesus monkeys. Toxicon 16, 543-SSO, 1978 .-Ef%cts of ataphylaeo~cal entaotoxin B were studied in aneathetimd rhesus monkeys. During the period from 6 to 11 hr following i.v. igjection of the toxin (1 "0 mg/kg), respiratory quotient increased, while functional t+esidual capacity, OOi output, O= oo»sumption and expirod COs concentration da~esaed . By 11 "5 hr, the surface tension of lung extracts and total lung water content increased, as shown by simultaneous accumulations of extratxllular Na+ and water. These results provide evidence to support a hypothesis that pulmonary dysfunction and terminal pulmonary edema contribute to dealt during enterotoxemia by staphylococcal B in rhesus monkeys. INTRODUCTION
Several staphylococcal enterotoxin B-induced physiologic changes, including peripheral capillary pooling (B>r1seL, 1972), intracellular dehydration, hypovolemia (Ltv et al., 1976b) and decreased cardiac functions (Lru et al., 1977) have been considered as possible causes of death during such toxemia in rhesus monkeys, the exact mechanism for induction of irnversible shock during enterotoxemia is still unknown. Pathologic studies revealed that pulmonary interstitial edema and increased lung weights were associated with i.v. inoculation of staphylococcal eaterotoxin B in monkeys (FI1vlcoi.D, 1%7 ; íSTILES and DeNrvISroN, 1971). This investigation was undertaken to study changes induced by this enterotoxin on pulmonary function, metabolic rate and arterial blood gas tensions, as well as lung water content, distribution of electrolytes, and surface tension in anesthetized monkeys. ALTHOUGH
MATERIALS AND METHODS
Healthy male rhesus monkeys (Maaaca »wlatta) wroighing 3ß-S"9 kg were allocated into control (N~9) and toxin-inoculated groups (N6~. The latter group of monkeys had no detectable serum antibody against staphylaooocal enterotoxin B prior to their use. Approximately ~ hr before the expa~imemt, urtilstalal polyethylene catheters (PE 190, i.d.~1"19 mm, o.d.~1"70 mm) were placed in the femoral artery and vein "In conducting the research described in this report, the investigators adhered to the "Guide for the Caro and Use of Laboratory Animals," as promulgated by the Committx on the Revision of the Guide for Laboratory Animal Facilities and Care of the Institute of Laboratory Animal Raoaroea, National Research Council . The facilities are fully accredited by the .4rlaícan Association for Accreditation of Laboratory Animal Care. The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense. This work was reported in part at the Fall Mating of the American Physiological Society, Philadelphia, Pa., August, 1976 [Physiologist, Washington 19, 273 (197] . 543
344
C. T. LIU, R. D. DELAUTER, M. J. GRIFFiN and C. L. HADICK
under Ketamine anesthesia. Monkeys were restrained in primate chairs for recovery from anesthesia (Ltu et al ., 1977)" Highly purified staphylococcal enterotoxin H ( >99 ~) (ScxArrrz et al., 1965) at a single dose of 1 mg/kg was injected into the femoral vein of experimental monkeys, while controls received only isotonic saline. Measured values were compared between normal and toxin~hallenged monkeys under identical experimental conditions . All monkeys were sedated with Ketamine (13 mg/Itg, i.m .) and placed in a supine position approximately 3"3 hr after i.v. injection of staphylococcal enterotoxin B. Endotracheal and intraesophageal intubations were completed within 30 min. Various pulmonary functions, metabolic changes, and blood pH and gas tensions were determined hourly betweat 6 and 11 hr after toxin or saline injection . However, one additional ezperituental monkey died 7"3 hr after enterotoxin inoculation ; its data are reported separately. Detailed information on txhniques for measuring respiratory and metabolic variables in anesthetized rhesus monkeys were described previously (Lrv and DeLAVreR, 1977). The basis of using such methods was that relatively constant respiratory and metabolic functions could be obtained for a period of 6 hr in lightly anesthetized normal monkeys. The voltune of Ox consumption was corrected for temperature, pressure and water vapor saturation . Arterial bloodpH, PO,, PCO,, HCO,' , total CO= and base excess were determined on a blood gas analyzer (Model 163, Conning Scirntific Instrtuneats, Medfield, Mass .) . Within l5 min after completion of pulmonary studies, various tissue samples including a lobe of the right lung, were excised from the anesthetized monkey. Lung samples were immediately blotted with absorbent paper to remove surface blood and for determinations of surface tension, water contrnt, total lipids, phospholipid and electrolytes p> including Na+, K+ (.OvsRtNArt and DAMS, 1947), Cl' (CoTt,ove et al., 1958) and phosphate phosphorus (Fts~ and SUHBAROW, 1925). Lung tissue was homogenized in distilled water (1 :10, w/v), and surface tension of the supernatant measured with a tensiometer (Model 21, Fisher Scientiftc Co., Pittsburgh, Prnn .) . Water content was determined by drying approximately 0"2 g of lung tissue to a rnnstant weight in an oven at 110°C. The Cl- content in the dry minced specimen was extracted for 20-24 hr in 3 ml of distilled water, while Nat, K+ and phosphate phosphorus were extracted from the homogeniud wet lung tissue with S ml of LO'á trichloroacetic acid . Distributions of intracellular and extracellular water and electrolytes in the lung were calculated according to the method of Bertsort et al., (1956) . Tissue phosphate extract was determined as total acid-soluble and inorganic acid-soluble fractions. The former was prepared using concentrated HaSOa digestion at 3í0°C and the latter proceeded without acid digestion . Organic acid-soluble phosphate was calculated from the difference between total and inorganic acid soluble phosphorus . Total lipids in the lung were extracted with a chloroform-methanol mixture (2 :1 v/v) for 20-24 hr at room temperature. The weight of total lipids in the lung was measured gravimetrically after complete evaporation of the solvent from the purified extract in a vacuum oven. Phosphorus contrnt of phospholipid was determined by the method of BARTr.Err (1959) . The phospholipid concentration was obtained by multiplying the phosphorus value by a factor of 25 . Values obtained from the experiments were compared using analysis of variance with repeated measurements. The values at 6 hr were used as the base litres for each monkey to test for significant changes over time. Further, differences from base lines for the control and enterotoxin-inoculated groups were also compared by an independrnt t-test . The Null hypothesis was rejected at the S"ó level.
Pulmonary functions and blood gases
RESULTS
Effects of i.v. inoculation of staphylococcal enterotoxin B on tidal volume, pulmonary ventilation and pulmonary mechanics in anesthetized rhesus monkeys breathing room air for (1 hr are summarized in Table 1 . No significant changes were found ; however, dynamic pulmonary resistance, functional residual capacity and expired COz concentration decreased significantly as compared to control monkeys in the later period (8-ll hr) after toxin injection (Fig. l). The respiratory rate was maintained relatively constant as compared with controls, in which decreased values were observed as a possible result of continuous anesthesia (Fig. 2). Further, one monkey that died earlier (at 7~5 hr) showed increased respiratory rate, dynamic pulmonary resistance and arterial blood PCOz while its tidal volume, dynamic pulmonary compliance, intraesophageal pressure, expired air flow and arterial P02 decreased markedly from control values (Table 2). No change in blood pH was demonstrated (Table 2). As compared to controls, rhesus monkeys showed significantly decreased O~ consumption and increased respiratory quotient values at 6-8 hr after toxin inoculation (Fig. 3). However, the magnitude of changes in Oz consumption and respiratory quotient remained unaltered
SEB and Respiration in
Monkeys
343
TADLE I . EPPECrs OF STAPHYLOCOCCAL ENTEROTOXIN B (SEB) ON TIDALVOLUK, PULMONARY VENTILATION AND PULMONARY MECHAMCd nV AIV~rüETIZED RHióUB MOAi1~Y8 DREATHINO ROOM AIR COI~ARED i0 ODNTROLS Variable
Tidal volume (ml) Minute volume (L/min) Intraesophageal pressure (cm H_O) Transpneumotach pressurc(cmH~O) Transpuhnonary pressure (cm HSO) Expiratory flow (ml/sec) Inspiratory flow (ml/sec) Dynamic pulmonary compliance (ml/cm H,O) Specific compliance (compliance/FRC x 10~ ~) 'Controls,
N=9;
9
SEB,
~
Values by hr post-SEH (mean f S.E.) 6 7 9 11 3Sí4 36f4 41 f6 36íS 38f 10 38f 7 32 íS l "36í0" 16 O"98í0"13 l "44í0"26 l "25í0"17 1 " 16í0A8 l"28í0"17 l "07í0"14 -S"7 f0"6 -S"6 f0"8 -7"1 f0"9 -4"78f 0"9 -S"59f 1 "4 -S"42 f 1"S -6"40f1 "8 1 "13 f0"09 0"85 f0"07 1 "OS íO"12 O"93í0"10 O"91í0" 16 O"98í0"12 O"90í0"09 ~"54f0"SS --4"7Sí0" 78 -6"O3í0"91 -3"85f0"85 -4"tí9 f 1 "22 --4"44f1 "42 -530f 1 "69 66"6 ítí"1 56"9 f8"7 61 "9 í7"S 60"6 f 10 59"6f 11 66"2 f 11 61 "8 f10 64"0 f5" 1 48"4 f3"7 59"S f6"8 52"8 f6 Sl " 3f9 SS"6 f7 SI "1 f3 8~2 f0"9 9"4 f1 "8 7"9 íl "7 ß" 6 f 1 "7 7" 1 f 1"1 9"1 f1 "9 6"8 í 1 "S 72f9 83f 14 S2í 7 77f 18 71 f 13 101 f22 113 f48
Group' Control SEB Control SEB Control SEB Control
S®
Control SEB Control SEB Control SEB Control SEB Control SEH
N=6.
r 0
6
1
~!
q
II
HOUIIS
fla . 1.
EFPECT oF rNTRAVENOVa srAPHYLOOOCCAL ENTmoTOxtx H (SEH) (1 ma/ka) oN DYNAMIC PULMONARY RF~.TrANCE, PUNCI70NAL R~UAL CAPACITY AND EXPIR® OOs TN AiVESrHETIZED RHEdUS MONICEY3 .
as a function of time between 6 and 11 hr after staphylococcal enterotozin B inoculation. Although C02 output and expired CO s concentration were signiScantly decreased at 11 and 9-11 hr, respectively, after toxin inoculation as compared with the control group of monkeys
C. T. LIU, R. D. DELAUTER, M. J. GRIFFIN and C. L. HADICK
S46
6 viW
U Y U
a
HOURS FB3.
2. EPFECT OF INTRAYENIWS STAPÜYLOCOCCAL ENTEAOTOXIN B (SEB) RESPIRATORY RATE IN ANESTHETIZED RHESUS MONKEYS .
(I mg/kg)
ON
TABLE 2. CHANGES IN PULMONARY FUNCTIONS AND ARTERIAL BLOOD pH, PO3 AND PCO, DURING rmTnmvAt srAPHYLOCOCCAL ENTFaoTOxIN B (SEB) ENTEROroxEMu (O'S br IIEFORE DBATH) OOMPARED TO OONTROLS
ValUe3 (meanfS.E .) Control SEB
Variable Tidal volume (IM Raapitatory rata (cycle/min) Dynamic pulmonary compliance (mllcm HBO) Dynamic pulmonary resistance (cm H~O/liter/sec) Intraesopha,eal pressure (cm H=O) Expired airflow (ml/sec) pH Artanal Blood POs (mm Hg) PCO= (mm Hg) fn i 201
Fra. 3.
OXYOI?N
38 f 13 33 f S 8~3=4~3 31 ~-7
19 57 1 ~8 168
~~3~0~7 62 i2 7~375~0~008 88~6 f4~9 29-0 f 2~7
-IS~7 47 7S18 33~3 38~8
oxwcn ca~giwrT~aa
O CONT11p~,f lN.f1 " fCf ~N ." 1 ~ ~spOf
EFFECT O! INTRAVENOUS SiAPHYL000CCAL BNTEROTOXIN B (SEB) (1 mg/1cg) oN COI~tJMI"rFON AND RE4IRATORY QUOTIENT IN ANESTHETIZED RHESUS MONKEYS .
SEB and Respiration in Monkeys
2 ro E w i 1 a
O
z"ce i i
34 7
eoz ounuT
I
_2
_ , .J i
0
6
7
B HOURS
9
i0
~I
FIG. 4. EFFECT OF INTRAVENOUS STAPHYLOCOCCAL ENTEROTOXIN B (SEB) (I mg/kg) ON COZ OUTPUT AND EXPIRED COz DIJRING Oz BREATHING IN ANFSrHETIZED RHESUS MONKEYS.
TABLE
3.
Variable pH
EFFECTS OF STAPHYLOCOCCAL ENTEROTOXIN B (SEB) ON ARTERLAL BLOOD pH, GAS 7ENSION, TOTAL COz AND BASE EXCF~S IN ANPárHETIZED RHESUS MONKEYS BREATHING PURE Oz Group'
Control SEB PO~ (mm Hg) Control SEB Control PCOz (mm Hg) SEB HCO,' (mmole/liter) Control SEB Total CO, (mmole/liter) Control SEB Base excess (mmole/liter) Control SEB 'Controls, N~9, SEB, N=6.
Values by hr post-SEB (IneaIt~S.E .) 6 7 9 11 7974f0"009 7"362f0"008 7"365f0"Ol 7"373f0-013 7"394f0"020 7"383f0-017 7"378f0"021 367f32 389f23 411 f 16 413f17 413f24 392f17 399±30 33"4 ~2 "4 33-0 f2 "8 31~3 f2 "6 34"2 f3 "3 33 "3 -_~-2~7 32" 1 y3-0 29 "2 ~3~3 19" 1 f 1 "S 19-0 -~ 1 " 7 18 " 1 -~ 1 ~7 18 "1 f2-0 18 "9 ~-1~9 16"4 f1~7 13"9 -2 "2 ZO"4 =1 ~3 20"6 +_ 1 "7 19"6 == I ~6 21 ~3 ± 13 21 "9 ~ 1 "3 20"3 f l "6 19"0 ~2~5 -3 "7 f 1 "3 ~"2 f 1 "4 -3-0 f 1 "4 ~"7 fl "2 -3 "9 a-1~3 -S"9 fl "2 -6"S -~2"0
(Fig. 4), arterial blood pH, PO=, PC02, HCO, -, total C02 andbaseexcess showed little or no changes during the entire I 1-hr experimental period (Table 3). Lung surface tension aiul biochtmical changes Although plasma water content and electrolytes concentrations were not altered after inoculation of staphylococcal enterotoxin B in anesthetized rhesus monkeys ('Table 4), surface tension, organic acid-soluble phosphorus, total water content, extracellular Na+ (mF.q/kg fat-free wet tissue) and total C!- (mEq/fat frce dry tissue) of the lung increased significantly as compared with lungs from control monkeys (Tables 4 and 5). There was also an apparent shift: of intracellular lung water and Na+ to the extracellular space in toxinchallenged monkeys (Table 4). No significant changes were observed in K+ distribution, total lipids, phospholipids and total and inorganic acid-soluble phosphorus of lungs 11-12 hr after a lethal i.v. dose of staphylococcal enterotoxin B ('Tables 4 and 5).
348
C . T . LIU, R . D . DELAUTER, M. J . GRIFFIN and C. L . HADICK
TABLE 4. CHANGES IN WATER AND ELECTROLYTE IN PtASMA AND THE LUNG OF.STAPHYL000CCAL Ei~'rEROTOXFN B (SEBFINOCULATED RHFSUS MONKEYS Sample Plasma
Variable
H=O (g/dl) NaT (mEq/liter) K- (mEq/liter) CI - (mEq/liter) Lung Total Hx0 (g/kg FFWT') Extracellular H,O (g/kg FFWT) Intracellular H,O (g/kg FFWT) Total Na (mEq/kg FFW'i~ Total Na (m1Eq/kg FFDTt) Intracellular Na (mlF.q/kg intracellular HBO) Extracellular Na (mEq/kg FFW'1~ Total K (mEq/kg FFWT) Total K (mEq/kg FFDT) Intracellular K (mEq/kg intracellular H:O) Extraoellular K (mEq/kg FFW'ï) Total Cl (mEq/kg FFWi) Total CI (mEglkg FFD7) 'FFWT=fat free wet tissue. tFFDT=fat free dry tissue . $N= 3 . 4N~6. ilBy independent t-tat, P
0041-0101178/1101-0343f02.00/0
EFFECTS OF STAPHYLOCOCCAL ENTEROTOXIN B ON FUNCTIONAL AND BIOCHEMICAL CHANGES OF THE LUNG IN RHESUS MONKEYS* C. T. Lnr, R. D. DeLAUrER, M. J . Gwr'FIN and C. L. HADICIc U.S . Army Medical Research Institute of Infectious Diseases, Fort Derrick, Frederick, Maryland 21701, U.S.A . (Acceptedjor publication 13 March 1978) C. T. Ltv, R. D. DEI,wrEa, M. J. GRIFFIN and C. L. H~ntctc. Efforts of staphylococcal cnterotoxin B on functional and biochemical changes of the lung in rhesus monkeys. Toxicon 16, 543-SSO, 1978 .-Ef%cts of ataphylaeo~cal entaotoxin B were studied in aneathetimd rhesus monkeys. During the period from 6 to 11 hr following i.v. igjection of the toxin (1 "0 mg/kg), respiratory quotient increased, while functional t+esidual capacity, OOi output, O= oo»sumption and expirod COs concentration da~esaed . By 11 "5 hr, the surface tension of lung extracts and total lung water content increased, as shown by simultaneous accumulations of extratxllular Na+ and water. These results provide evidence to support a hypothesis that pulmonary dysfunction and terminal pulmonary edema contribute to dealt during enterotoxemia by staphylococcal B in rhesus monkeys. INTRODUCTION
Several staphylococcal enterotoxin B-induced physiologic changes, including peripheral capillary pooling (B>r1seL, 1972), intracellular dehydration, hypovolemia (Ltv et al., 1976b) and decreased cardiac functions (Lru et al., 1977) have been considered as possible causes of death during such toxemia in rhesus monkeys, the exact mechanism for induction of irnversible shock during enterotoxemia is still unknown. Pathologic studies revealed that pulmonary interstitial edema and increased lung weights were associated with i.v. inoculation of staphylococcal eaterotoxin B in monkeys (FI1vlcoi.D, 1%7 ; íSTILES and DeNrvISroN, 1971). This investigation was undertaken to study changes induced by this enterotoxin on pulmonary function, metabolic rate and arterial blood gas tensions, as well as lung water content, distribution of electrolytes, and surface tension in anesthetized monkeys. ALTHOUGH
MATERIALS AND METHODS
Healthy male rhesus monkeys (Maaaca »wlatta) wroighing 3ß-S"9 kg were allocated into control (N~9) and toxin-inoculated groups (N6~. The latter group of monkeys had no detectable serum antibody against staphylaooocal enterotoxin B prior to their use. Approximately ~ hr before the expa~imemt, urtilstalal polyethylene catheters (PE 190, i.d.~1"19 mm, o.d.~1"70 mm) were placed in the femoral artery and vein "In conducting the research described in this report, the investigators adhered to the "Guide for the Caro and Use of Laboratory Animals," as promulgated by the Committx on the Revision of the Guide for Laboratory Animal Facilities and Care of the Institute of Laboratory Animal Raoaroea, National Research Council . The facilities are fully accredited by the .4rlaícan Association for Accreditation of Laboratory Animal Care. The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense. This work was reported in part at the Fall Mating of the American Physiological Society, Philadelphia, Pa., August, 1976 [Physiologist, Washington 19, 273 (197] . 543
344
C. T. LIU, R. D. DELAUTER, M. J. GRIFFiN and C. L. HADICK
under Ketamine anesthesia. Monkeys were restrained in primate chairs for recovery from anesthesia (Ltu et al ., 1977)" Highly purified staphylococcal enterotoxin H ( >99 ~) (ScxArrrz et al., 1965) at a single dose of 1 mg/kg was injected into the femoral vein of experimental monkeys, while controls received only isotonic saline. Measured values were compared between normal and toxin~hallenged monkeys under identical experimental conditions . All monkeys were sedated with Ketamine (13 mg/Itg, i.m .) and placed in a supine position approximately 3"3 hr after i.v. injection of staphylococcal enterotoxin B. Endotracheal and intraesophageal intubations were completed within 30 min. Various pulmonary functions, metabolic changes, and blood pH and gas tensions were determined hourly betweat 6 and 11 hr after toxin or saline injection . However, one additional ezperituental monkey died 7"3 hr after enterotoxin inoculation ; its data are reported separately. Detailed information on txhniques for measuring respiratory and metabolic variables in anesthetized rhesus monkeys were described previously (Lrv and DeLAVreR, 1977). The basis of using such methods was that relatively constant respiratory and metabolic functions could be obtained for a period of 6 hr in lightly anesthetized normal monkeys. The voltune of Ox consumption was corrected for temperature, pressure and water vapor saturation . Arterial bloodpH, PO,, PCO,, HCO,' , total CO= and base excess were determined on a blood gas analyzer (Model 163, Conning Scirntific Instrtuneats, Medfield, Mass .) . Within l5 min after completion of pulmonary studies, various tissue samples including a lobe of the right lung, were excised from the anesthetized monkey. Lung samples were immediately blotted with absorbent paper to remove surface blood and for determinations of surface tension, water contrnt, total lipids, phospholipid and electrolytes p> including Na+, K+ (.OvsRtNArt and DAMS, 1947), Cl' (CoTt,ove et al., 1958) and phosphate phosphorus (Fts~ and SUHBAROW, 1925). Lung tissue was homogenized in distilled water (1 :10, w/v), and surface tension of the supernatant measured with a tensiometer (Model 21, Fisher Scientiftc Co., Pittsburgh, Prnn .) . Water content was determined by drying approximately 0"2 g of lung tissue to a rnnstant weight in an oven at 110°C. The Cl- content in the dry minced specimen was extracted for 20-24 hr in 3 ml of distilled water, while Nat, K+ and phosphate phosphorus were extracted from the homogeniud wet lung tissue with S ml of LO'á trichloroacetic acid . Distributions of intracellular and extracellular water and electrolytes in the lung were calculated according to the method of Bertsort et al., (1956) . Tissue phosphate extract was determined as total acid-soluble and inorganic acid-soluble fractions. The former was prepared using concentrated HaSOa digestion at 3í0°C and the latter proceeded without acid digestion . Organic acid-soluble phosphate was calculated from the difference between total and inorganic acid soluble phosphorus . Total lipids in the lung were extracted with a chloroform-methanol mixture (2 :1 v/v) for 20-24 hr at room temperature. The weight of total lipids in the lung was measured gravimetrically after complete evaporation of the solvent from the purified extract in a vacuum oven. Phosphorus contrnt of phospholipid was determined by the method of BARTr.Err (1959) . The phospholipid concentration was obtained by multiplying the phosphorus value by a factor of 25 . Values obtained from the experiments were compared using analysis of variance with repeated measurements. The values at 6 hr were used as the base litres for each monkey to test for significant changes over time. Further, differences from base lines for the control and enterotoxin-inoculated groups were also compared by an independrnt t-test . The Null hypothesis was rejected at the S"ó level.
Pulmonary functions and blood gases
RESULTS
Effects of i.v. inoculation of staphylococcal enterotoxin B on tidal volume, pulmonary ventilation and pulmonary mechanics in anesthetized rhesus monkeys breathing room air for (1 hr are summarized in Table 1 . No significant changes were found ; however, dynamic pulmonary resistance, functional residual capacity and expired COz concentration decreased significantly as compared to control monkeys in the later period (8-ll hr) after toxin injection (Fig. l). The respiratory rate was maintained relatively constant as compared with controls, in which decreased values were observed as a possible result of continuous anesthesia (Fig. 2). Further, one monkey that died earlier (at 7~5 hr) showed increased respiratory rate, dynamic pulmonary resistance and arterial blood PCOz while its tidal volume, dynamic pulmonary compliance, intraesophageal pressure, expired air flow and arterial P02 decreased markedly from control values (Table 2). No change in blood pH was demonstrated (Table 2). As compared to controls, rhesus monkeys showed significantly decreased O~ consumption and increased respiratory quotient values at 6-8 hr after toxin inoculation (Fig. 3). However, the magnitude of changes in Oz consumption and respiratory quotient remained unaltered
SEB and Respiration in
Monkeys
343
TADLE I . EPPECrs OF STAPHYLOCOCCAL ENTEROTOXIN B (SEB) ON TIDALVOLUK, PULMONARY VENTILATION AND PULMONARY MECHAMCd nV AIV~rüETIZED RHióUB MOAi1~Y8 DREATHINO ROOM AIR COI~ARED i0 ODNTROLS Variable
Tidal volume (ml) Minute volume (L/min) Intraesophageal pressure (cm H_O) Transpneumotach pressurc(cmH~O) Transpuhnonary pressure (cm HSO) Expiratory flow (ml/sec) Inspiratory flow (ml/sec) Dynamic pulmonary compliance (ml/cm H,O) Specific compliance (compliance/FRC x 10~ ~) 'Controls,
N=9;
9
SEB,
~
Values by hr post-SEH (mean f S.E.) 6 7 9 11 3Sí4 36f4 41 f6 36íS 38f 10 38f 7 32 íS l "36í0" 16 O"98í0"13 l "44í0"26 l "25í0"17 1 " 16í0A8 l"28í0"17 l "07í0"14 -S"7 f0"6 -S"6 f0"8 -7"1 f0"9 -4"78f 0"9 -S"59f 1 "4 -S"42 f 1"S -6"40f1 "8 1 "13 f0"09 0"85 f0"07 1 "OS íO"12 O"93í0"10 O"91í0" 16 O"98í0"12 O"90í0"09 ~"54f0"SS --4"7Sí0" 78 -6"O3í0"91 -3"85f0"85 -4"tí9 f 1 "22 --4"44f1 "42 -530f 1 "69 66"6 ítí"1 56"9 f8"7 61 "9 í7"S 60"6 f 10 59"6f 11 66"2 f 11 61 "8 f10 64"0 f5" 1 48"4 f3"7 59"S f6"8 52"8 f6 Sl " 3f9 SS"6 f7 SI "1 f3 8~2 f0"9 9"4 f1 "8 7"9 íl "7 ß" 6 f 1 "7 7" 1 f 1"1 9"1 f1 "9 6"8 í 1 "S 72f9 83f 14 S2í 7 77f 18 71 f 13 101 f22 113 f48
Group' Control SEB Control SEB Control SEB Control
S®
Control SEB Control SEB Control SEB Control SEB Control SEH
N=6.
r 0
6
1
~!
q
II
HOUIIS
fla . 1.
EFPECT oF rNTRAVENOVa srAPHYLOOOCCAL ENTmoTOxtx H (SEH) (1 ma/ka) oN DYNAMIC PULMONARY RF~.TrANCE, PUNCI70NAL R~UAL CAPACITY AND EXPIR® OOs TN AiVESrHETIZED RHEdUS MONICEY3 .
as a function of time between 6 and 11 hr after staphylococcal enterotozin B inoculation. Although C02 output and expired CO s concentration were signiScantly decreased at 11 and 9-11 hr, respectively, after toxin inoculation as compared with the control group of monkeys
C. T. LIU, R. D. DELAUTER, M. J. GRIFFIN and C. L. HADICK
S46
6 viW
U Y U
a
HOURS FB3.
2. EPFECT OF INTRAYENIWS STAPÜYLOCOCCAL ENTEAOTOXIN B (SEB) RESPIRATORY RATE IN ANESTHETIZED RHESUS MONKEYS .
(I mg/kg)
ON
TABLE 2. CHANGES IN PULMONARY FUNCTIONS AND ARTERIAL BLOOD pH, PO3 AND PCO, DURING rmTnmvAt srAPHYLOCOCCAL ENTFaoTOxIN B (SEB) ENTEROroxEMu (O'S br IIEFORE DBATH) OOMPARED TO OONTROLS
ValUe3 (meanfS.E .) Control SEB
Variable Tidal volume (IM Raapitatory rata (cycle/min) Dynamic pulmonary compliance (mllcm HBO) Dynamic pulmonary resistance (cm H~O/liter/sec) Intraesopha,eal pressure (cm H=O) Expired airflow (ml/sec) pH Artanal Blood POs (mm Hg) PCO= (mm Hg) fn i 201
Fra. 3.
OXYOI?N
38 f 13 33 f S 8~3=4~3 31 ~-7
19 57 1 ~8 168
~~3~0~7 62 i2 7~375~0~008 88~6 f4~9 29-0 f 2~7
-IS~7 47 7S18 33~3 38~8
oxwcn ca~giwrT~aa
O CONT11p~,f lN.f1 " fCf ~N ." 1 ~ ~spOf
EFFECT O! INTRAVENOUS SiAPHYL000CCAL BNTEROTOXIN B (SEB) (1 mg/1cg) oN COI~tJMI"rFON AND RE4IRATORY QUOTIENT IN ANESTHETIZED RHESUS MONKEYS .
SEB and Respiration in Monkeys
2 ro E w i 1 a
O
z"ce i i
34 7
eoz ounuT
I
_2
_ , .J i
0
6
7
B HOURS
9
i0
~I
FIG. 4. EFFECT OF INTRAVENOUS STAPHYLOCOCCAL ENTEROTOXIN B (SEB) (I mg/kg) ON COZ OUTPUT AND EXPIRED COz DIJRING Oz BREATHING IN ANFSrHETIZED RHESUS MONKEYS.
TABLE
3.
Variable pH
EFFECTS OF STAPHYLOCOCCAL ENTEROTOXIN B (SEB) ON ARTERLAL BLOOD pH, GAS 7ENSION, TOTAL COz AND BASE EXCF~S IN ANPárHETIZED RHESUS MONKEYS BREATHING PURE Oz Group'
Control SEB PO~ (mm Hg) Control SEB Control PCOz (mm Hg) SEB HCO,' (mmole/liter) Control SEB Total CO, (mmole/liter) Control SEB Base excess (mmole/liter) Control SEB 'Controls, N~9, SEB, N=6.
Values by hr post-SEB (IneaIt~S.E .) 6 7 9 11 7974f0"009 7"362f0"008 7"365f0"Ol 7"373f0-013 7"394f0"020 7"383f0-017 7"378f0"021 367f32 389f23 411 f 16 413f17 413f24 392f17 399±30 33"4 ~2 "4 33-0 f2 "8 31~3 f2 "6 34"2 f3 "3 33 "3 -_~-2~7 32" 1 y3-0 29 "2 ~3~3 19" 1 f 1 "S 19-0 -~ 1 " 7 18 " 1 -~ 1 ~7 18 "1 f2-0 18 "9 ~-1~9 16"4 f1~7 13"9 -2 "2 ZO"4 =1 ~3 20"6 +_ 1 "7 19"6 == I ~6 21 ~3 ± 13 21 "9 ~ 1 "3 20"3 f l "6 19"0 ~2~5 -3 "7 f 1 "3 ~"2 f 1 "4 -3-0 f 1 "4 ~"7 fl "2 -3 "9 a-1~3 -S"9 fl "2 -6"S -~2"0
(Fig. 4), arterial blood pH, PO=, PC02, HCO, -, total C02 andbaseexcess showed little or no changes during the entire I 1-hr experimental period (Table 3). Lung surface tension aiul biochtmical changes Although plasma water content and electrolytes concentrations were not altered after inoculation of staphylococcal enterotoxin B in anesthetized rhesus monkeys ('Table 4), surface tension, organic acid-soluble phosphorus, total water content, extracellular Na+ (mF.q/kg fat-free wet tissue) and total C!- (mEq/fat frce dry tissue) of the lung increased significantly as compared with lungs from control monkeys (Tables 4 and 5). There was also an apparent shift: of intracellular lung water and Na+ to the extracellular space in toxinchallenged monkeys (Table 4). No significant changes were observed in K+ distribution, total lipids, phospholipids and total and inorganic acid-soluble phosphorus of lungs 11-12 hr after a lethal i.v. dose of staphylococcal enterotoxin B ('Tables 4 and 5).
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C . T . LIU, R . D . DELAUTER, M. J . GRIFFIN and C. L . HADICK
TABLE 4. CHANGES IN WATER AND ELECTROLYTE IN PtASMA AND THE LUNG OF.STAPHYL000CCAL Ei~'rEROTOXFN B (SEBFINOCULATED RHFSUS MONKEYS Sample Plasma
Variable
H=O (g/dl) NaT (mEq/liter) K- (mEq/liter) CI - (mEq/liter) Lung Total Hx0 (g/kg FFWT') Extracellular H,O (g/kg FFWT) Intracellular H,O (g/kg FFWT) Total Na (mEq/kg FFW'i~ Total Na (m1Eq/kg FFDTt) Intracellular Na (mlF.q/kg intracellular HBO) Extracellular Na (mEq/kg FFW'1~ Total K (mEq/kg FFWT) Total K (mEq/kg FFDT) Intracellular K (mEq/kg intracellular H:O) Extraoellular K (mEq/kg FFW'ï) Total Cl (mEq/kg FFWi) Total CI (mEglkg FFD7) 'FFWT=fat free wet tissue. tFFDT=fat free dry tissue . $N= 3 . 4N~6. ilBy independent t-tat, P
