Transient effects of histamine on microvascular fluid movement

M1CROVASCULARRESEARCH23, 316--328 (1982)

Transient Effects of Histamine on Microvascular Fluid Movement RONALD J. KORTHUIS, C . Y .

WANG, AND JERRY

B . SCOTT

Department of Physiology, Michigan State University, East Lansing, Michigan 48824 Received June 24, 1981

There have been many reports on the effect of local intraarterial (IA) histamine on the capillary filtration coefficient (CFC) and the isogravimetfic capillary pressure (P,~). CFC has been reported to increase during infusion of this agent but the reported magnitude of increase is widely variable. Similarly, histamine has been reported to cause little change or a decrease in Pci. It was felt that histamine may have some time-dependent effect on CFC and Pc~ and that this might explain, at least in part, the variation. T o test this hypothesis, CFC and Pci were measured in the isolated, denervated canine forelimb at timed intervals during infusion of local IA histamine (12 I~g base/min). Also, lymph and plasma samples were collected and lymph flow and lymph and plasma protein concentration were determined. Permeability-surface area. (PS) product ratios were estimated from steady-state lymph data. Propranolol (2-3 mg/kg iv priming dose and 123 txg/min locally) was administered throughout the experiment to inhibit possible catecholamine-mediated inhibition of histamine-induced increases in fluid andprotein efflux. CFC averaged 0,013 ml/min/mm Hg/100 g at control and increased to 0.040 and 0.048 after 5 and 10 min of histamine, respectively. Subsequent CFC determinations were not different from control. Pc~ was not altered by histamine at this dose. The estimated PS ratio was 43. Control experiments were conducted in which propranolol and the saline vehicle were infused. No change in any variable in the control group occurred with time. These data indicate tiaat the effect of histamine on the small-pore system, as reflected by changes in CFC, is highly transient.

INTRODUCTION It is well known that local intraarterial histamine administration increases the movement of fluid and protein from the vascular to extravascular space, resulting in an increased interstitial fluid volume and lymph protein concentration (Haddy et al., 1976). Associated with these changes is an increase in the capillary filtration coefficient (CFC) (Kjellmer and Odelram, 1965; Diana et al., 1972; McNamee and Grodins, 1975; Flynn and Owen, 1977; Rippe and Grega, 1978) and little change or decrease in the isogravimetric capillary pressure (Pc,) (Dietzel et al., 1969; Diana et al., 1972; and McNamee and Grodins, 1975). Although histamine administration always results in an increase in CFC, the reported magnitude of increase is widely variable. For example, Kjellmer and Odelram (1965) reported a 6-fold increase in CFC of cat calf muscle during infusion of 27.0 ixg/min 316 0026-2862/82/030316-13502.00/0 Copyright © 1982by AcademicPress, Inc. All rights of reproductionin any formreserved. Primed in U.S.A.

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317

histamine. Diana et al. (1972) noted a twofold increase in CFC during infusion of 20-60 ~g/min histamine int6 isolated dog hindlimbs. Rippe and Grega (1978) measured a 3-fold increase :in CFC during perfusion of 30-60 Ixg histamine/ml blood intorat hindlimbs. McNamee and Grodins (1975), using isolated dog gracilis muscles, reported a 36-fold increase in CFC when 3.3-5 Ixg histamine/ml was added to the perfusate. Flynn. and Owen (1977) measured CFC during infusion of 3 ~g/kg min histamine into isolated skinned cat hindlimbs and found CFC increased by almost 2-fold. Similarly~ reported changes in Pc, during histamine are variable. Dietzel et al. (1969) infused histamine at varying doses and noted a dose-dependent fall in Pci from 10.7 mm Hg at control to 7.7 mm Hg at the highest dose of histamine (68 ~g/min). McNamee and Grodins (1975) reported a much larger fall in Pc, (18.6 to 4.5 mm-Hg) during perfusion of dog gracilis muscle with blood :containing 3~3-5 p.g histamine/ml blood~ Diana et al. (1972) found, in the dog hindlimb, that histamine (1-50 ~g/min) did not alter Pc,. The difference in reported changes in CFC and Pc, may be attributed to differences in (1) species, (2) tissues, (3) dosages, and/or (4) time of measurement after the onset o f histamine administration. In the present study, we tested the hypothesis that t h e time-dependent effects of histamine on CFC and Pc, may contribute to the differences in the literature. Further, a modified method for calculation of CFC is presented. MATERIALS AND METHODS Isogravimetric Forelimb Preparation Adult mongrel dogs of either sex were anesthetized with sodium pentobarbital (25 mg/kg iv) and placed on positive-pressure respiration. Tidal volume and respiratoryrate were adjusted to maintain blood gases and pH within the normal range. The right jugular vein and carotid artery were isolated and cannulated for infusion of drugs and measurement of systemic arterial pressure. The skin of the left forelimb was circumferentially divided about 2-4 cm above the elbow (Fig. t). The left brachial artery and vein and caphalic vein were isolated in preparation for cannulation. The muscles and remaining connective tissue were severed with electrocauteryl Special care was taken to ensure minimal bleeding from the cut surface of the muscles. The humerus was cut and the cut ends packed with bone wax. Immediately prior to heparinization (10,000 U iv), the :forelimb nerves were severed. The brachial artery was temporarily occluded (I-2 min) and the brachial and cephalic veins were cannulated with lengths of PE 320 tubing. Venous outflows were combined and directed via a Y tube through a '~-iri. fine-adjustment needle valve to a reservoir, R~. A second reservoir, Re, partially filled with saline, was also inserted in this circuit. R2 could be eliminated from the circuit by a clamp. However, when open, adjustment of height allowed maintenance of an isogravimetric state when measuring Pc,. Blood from Rl w a s returned to the animal via a femoral vein. The needle valve permitted the precise venous pressure manipulations that were necessary for the determination of CFC. An extracorporeal circuit containing a blood pump was then interposed

318

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in between the femoral and brachial arteries. Following cannulations, the limb was placed on a wire mesh grid and suspended from a sensitive strain gauge (Unimeasure, Inc.). The sensitivity of the gauge was adjusted so that placement of a 5-g weight on the grid produced a pen deflection of 20-25 mm on the recording paper. Blood flow to the limb was adjusted in the control period so that the limb remained in an isogravimetric state. Arterial, perfusion, and venous pressures were recorded with low-volumedisplacement pressure transducers (Statham, model P23Gb) and continuous recordings of pressures and limb weight were made with a direct writing oscillograph (Grass model 5D polygraph). In some experiments, two to three lymph vessels located 2 cm below the elbow on the medial aspect of the left forelimb near the cephalic vein were isolated and occluded and one was cannulated with a 10-cm length of PE 10 tubing. Lymph was collected for 10-min periods in small graduated cylinders. Lymph and plasma protein concentrations were determined spectrophotometrically (Beckman BD spectrophotometer) by the method of Waddell (1956) or by a modified biuret technique (Accu-Stat total protein analyzer) (Tietz, 1970). In all experiments, because of the recent finding (Rippe and Grega, 1978, and Grega et al., 1980) that the catecholamines antagonize histamine-induced increases in fluid and protein fluxes via interaction with the 13-receptors, propranolol (2-3 mg/kg body wt) was administered just after suspension of the limb from the strain gauge. In addition, throughout the experiment 125 ixg/min was infused intraarterially into the isolated forelimb. Adequacy of [3-blockade was periodically tested by challenge with a 2-1xg bolus injection of isoproterenol. Blockade was considered adequate when no decrease in perfusion pressure was noted. Data w e r e analyzed by analysis of variance (randomized block design) and means were compared by Student-Neuman-Keuls test. A p value of less than 0.05 was considered significant.

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EFFECTS OF HISTAMINE

319

Determination of Pc, PC, was determined by the stop flow method of Johnson (1965). Briefly, arterial inflow and venous outflow were simultaneously occluded. By adjusting the height of R2, vascular hydrostatic pressure was adjusted to maintain the limb in an isogravimetric state. This isogravimetric state was sustained for at least I rain. The venous pressure (same as perfusion pressure) at which the limb was maintained isogravimetric at zero flow was taken as Pc,. At least 10 min of recovery time was allowed between each stop flow determination. In a few experiments, both the stop flow method and the method of Pappenheimer and Soto-Rivera (1948) for determination of Pol were compared and the results were indistinguishable.

Determination of CFC CFC was determined by a modification of the method of Pappenheimer and Soto-Rivera (1948). After measuring an initial venous pressure (Pv,) and filtration rate (F1, g/min), venous pressure was elevated 4-8 mm Hg and following the vascular transient, venous pressure (Pv2) and filtration rate (F2) were recorded. CFC was then calculated according to the formula F2 - FI

CFC - Pv2 - Pv,"

(1)

The filtrate was assumed to have a unit density; thus CFC was expressed as milliliters per minute per millimeter Hg per 100 g. A derivation of this equation is given under Treatment of Data.

Determination of Permeability-Surface Area (PS) Product Ratios In these experiments, a 10-rain control lymph sample was taken. Histamine was then infused at 12 Cg base/rain and four subsequent 10-min lymph samples were taken at the 15th, 35th, 55th, and 75th minutes. During histamine infusion, the second and third lymph samples were identical suggesting a steady state. Thus, these data were used in the estimation of PS ratios according to the formula (Kozlowski et al., 1981): (PS)2 (PS)l

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11 R1 1 - R~ '

(2)

where l = single lymph flow, R = lymph-to-plasma protein concentration ratio, and subscripts I and 2 refer to control and lymph steady state during histamine.

Treatment of Data The original method of Pappenheimer and Soto-Rivera (1948) requires isogravimetric states for determination of CFC. This method worked well under normal conditions. However, histamine infusion causes large amounts of fluid to escape to the extravascular space. In previous studies, blood flow to the organ under investigation was reduced to an ischemic state so that the organ remained isogravimetric. We wished to determine the effect of histamine on CFC without

320

KORTHUIS, WANG, AND SCOTT

an isogravimetric state, i.e., without the possible complicating effects of ischemia. The theoretical basis is as follows. Using the Starling equations and thePoiseuiUe equation, F = C F C (Pc - Pc,),

(3)

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(4)

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(5)

where F = rate of fluid movement across the microvasculature, ( + ) = filtration, ( - ) = reabsorption, Pc, Pt = capillary and tissue hydrostatic pressures, *re, "rr, = capillary and tissue colloid osmotic pressures, tr = osmotic reflection coefficient, Rv = venous resistance, Qv = venous flow rate, Pv = venous pressure, we obtained the equation (Eq. (1)) we used to obtain C F C . After recording an initial venous pressure (Pv,) and filtration rate (F1), venous pressure is elevated. The ensuing increased filtration rate (F2) is composed of two phases: an initial, rapid increase in limb weight attributable to vascular volume changes and a slower component attributable to filtration (see Fig. 2). The filtration rate (F2) and venous pressure (Pv~) are m e a s u r e d during this slow

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component. Because this elevation of venous pressure increased capillary pressure,-the two filtration states can be described by Eq. (3): F, = C F C (Pc, - Pc),

(6)

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(7)

We assumed that conditions in and around the microvascular wall are not altered to any significant degree between the two filtration states, such that C F C and Pc, are not greatly influenced. This assumption is probably valid since only 20-30 sec elapsed between the first and second filtration state determinations (Fig. 2). For each C F C d e t e r m i n a t i o n , F1, Pv,, F2, and Pv2 are obtained experimentally. Thus Eq. (6) can-be subtracted from Eq. (7) to obtain F2 - Vl = C F C (Pc2 - Pc).

(8)

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(9)

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(10)

Our experiments show (Fig. 3) venous resistance is constant over a wide range of venous pressures; thus Rv, and Rv~ can be regarded as equal. Qv~ was less than Q,, owing to the increased rate of fluid filtration brought about by the increased capillary pressure. However, the filtration rate F is much less than Qv and Qvl and Q,~ never differed by more than 5%. Thus, Q,, and Qv~ are approximately equal. TherefOre, Eq. (9) can be subtracted from Eq. (10) to obtain Pc2 - Pc, = Pv~ - Pvl-

(11)

Substituting (Pv~ - P~l) for (Pc~ - Pc,) in Eq. (8) and rearranging we obtained Eq. (1). E x p e r i m e n t a l Protocol

In the first series of experiments, propranolol (2-3 mg/kg priming dose and 123 tzg/min locally) was administered. After [3-blockade was complete as judged by no response to isoproterenol, C F C and Pc; were determined periodically over 85 min of propranolol infusion. In the second series of experiments, after control C F C and Pc, determinations, histamine (12 p.g base/min) was infused concomitantly with propranolol Over 85 min. C F C was determined during the 5th, 10th, 15th, 20th, 25th; 45th, 65th, and 85th minutes of histamine. Pc; was determined after the 25th, 45th, 65th and 85th minutes. The thirdseries was similar to the second except that C F C was not determined and Pc, was measured during' the 5th, 15th, 25th, 45th, 65th, and 85th minutes of histamine. The dosage of histamine (12 p~g base/min) used in these experiments was

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selected because it is known to produce maximal hemodynamic effects as well as producing a noticeable gain in limb weight. RESULTS It is evident from Table 1 that infusion of saline alone had no effect on CFC and Pc, over the entire period of the experiment. In four additional animals, CFC and Pc, were measured before and after B-blockade and found to be identical. On the average, propranolol reduced systemic blood pressure from 145.0_+5.1 to 123.0_+4.9 mm Hg and pressure remained depressed at this level throughout the experiment. Perfusion pressure was unaffected by saline infusion. Intraarterial infusion of histamine (12 Ixg base/min) into the constantly perfused isolated B-blocked forelimb produced a sustained fall in systemic blood pressure and perfusion pressure (p<0.001, see Table 2). Lymph flow was markedly elevated (p<0.001) between the 15th and 65th minutes of histamine infusion but had returned to control by the 85th minute. Lymph protein concentration was also markedly elevated by the 35th minute and remained elevated at this level for the subsequent 50 min of histamine. Plasma protein concentration was not affected by histamine infusion at any point during infusion of this agent. Using

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the steady-state lymph flow and lymph and plasma protein concentration data, the ratio of estimated P S products of histamine to control was calculated to be 43. This indicates a large increase in permeability and/or surface area of the large-pore system. The effects of histamine on CFC and Pci are presented in Table 3. CFC averaged 0.013___0.001 ml/min/mm Hg/100 g during the control period. It was markedly elevated at the 5th and 10th minutes of histamine but was not significantly different from control at later times. The time course of the rate of weight gain by the forelimb was similar to the transient changes in CFC. That is, rate of weight gain by the forelimb was markedly elevated during the first 10 min of histamine and began to decrease over the subsequent period of the protocol, finally returning to near isogravimetric levels after 25 min of histamine. In the group of animals in which CFC was measured, it was impossible to determine Pc, at the 5th, 10th, 15th, and 20th minutes because of time constraints. Consequently, Pc, could not be assessed until after the 25th minute. In order to obtain earlier measurements, another series (n = 6) was conducted where Pci was also determined at the 5th and 15th minutes. Pc, measured at any time after the onset of histamine administration was not significantly different from control. DISCUSSION The data presented in Table 3 show the effect of histamine on CFC is transient with CFC increasing by about 3.5 times relative to control during the first 10 min of drug infusion. CFC measurements obtained after this time were not significantly different from control. Measurement of CFC provides a direct measure of transcapillary hydrodynamic conductivity which, in turn, is a product of the capillary surface area (small pore number) available for exchange and capillary permeability (small pore size) (Landis and Pappenheimer, 1963). Therefore, the changes in CFC induced by histamine are due to changes in capillary surface area and/or permeability. Although the present study does not provide data which distinguish between surface area and permeability, the contribution of changes in surface area may be less important than changes in microvascular permeability. Since perfusion pressure fell and remained unchanged throughout the infusion of histamine, and blood flow was held constant, it follows that vascular resistance remained constant and hence Surface area may have also remained constant. This line of reasoning indicates that permeability to water and small molecules at first increased and then decreased back to control. Presently, the mechanism responsible for the transient effect of histamine on CFC is unknown. However, it is unlikely that it is related to a 13-antagonistic action since the limb was [3-blocked throughout the experiment. It seems unlikely that time effects alone can account for the large variation in reported CFC. However, this study demonstrates a large transient effect of histamine on CFC. Thus time is an important factor which must be considered when examining the effect of this agent on the microvasculature. The finding that Pc, did not decrease at this dose of histamine agrees with the results of Diana et al. (1972) in dog hindlimb and is similar to the study of Dietzel et al. (1969) in the dog forelimb. The latter study reported a 2 mm Hg decrease

326

KORTHUIS, WANG,

A N D SCOTT

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in Pc, at a comparable dose. These investigators used a modified Student t test for examining a dose-response effect and it is possible that a more rigorous statistical test would have failed to show significance. In any event, it is surprising that this dose of histamine which increased lymph flow and protein concentration did not significantly decrease Per One possible explanation is that Pt and "trc remained constant. This coupled with a decrease in o" and little change or a slight decrease in ~rt would result in little change or a slight decrease in Per Evidence in support of the assumption that P~ was unchanged comes from the studies of Eliasson et al. (1974) who showed that the interstitial space of skeletal muscle is highly compliant. Thus large amounts of fluid can be mobilized from or added to this space with little change in P~. Even if one assumes that tissue compliance behaves as described by Guyton (1965) for subcutaneous tissue, it is unlikely that P~ was altered. According to Guyton (1965), tissue compliance is very low at "normal" P~, but becomes higher when tissue pressure is greater than 0 mm Hg. Brace and Guyton (1977) have measured Pt by the capsule technique in the isolated canine forelimb and found it to be slightly positive (+ 1 mm Hg). Thus in the present studies due to the isolation procedures used it is probable that compliance of the interstitial space was high. Because the limb weight was increased by only 8-10% in the present studies, it seems unlikely that Pt was significantly altered. In the present study, ~c did not change and also, at least initially, "trt may not have changed or even slightly decreased. The latter could result from a proportionately greater efflux of water than protein. Finally, several studies suggest that or decreases during histamine infusion (Dietzel et al., 1969, and McNamee and Grodins, 1975). However, this explanation seems implausible after 15 min of histamine because CFC had returned to control values. Thus during the latter stages of histamine infusion, we have no explanation for the unaltered Pcl. The steady state in lymph flow and protein was attained after 35 min of histamine infusion. The ratio of estimated P S values obtained from these data increased by about 43-fold. Although there is some dispute (Visscher et al., 1956) as to whether lymph data truly represent what is happening outside the microvasculature the calculation nevertheless indicates a large increase in permeability and/or surface area of the large pores. The fact that the effect of histamine on lymph flow and protein concentration was longer lasting than the effect on CFC suggests that the action of histamine on the large-pore system was sustained relatively longer. Recent reports support this suggestion. Svensjo and Joyner (1981) have shown that histamine administration results in a transient increase in permeability to large molecules which returns to control values within 60 min. Further, Katz (1981) reported that histamine acts on the capillary to transiently increase the transport of protein via convective transport through a pore system of increased size. These data indicate that histamine-induced increases in macromolecular permeability are mediated by a system of enlarged pores and that the effect of histamine on these pores is relatively longer lasting than its effect on the small-pore system. In summary, these results show that the effect of histamine on the small-pore system, as reflected by changes in CFC, is transient. This important time-dependent effect should be carefully taken into account in all permeability studies.

328

KORTHUIS, WANG, AND SCOTT

We suggest that the maximum increase in CFC should always be found and reported. In our case, the maximum occurred within 10 min after the onset of histamine. The present studies clearly show that one may be led to erroneous conclusions if permeability measurements are taken at arbitrary times during histamine infusion.

ACKNOWLEDGMENT This work supported in part by Public Health Service Grant HC-24363.

REFERENCES BRACE, R. A., AND GUYTON, A. C. (1977). Interaction of transcapillary Starling forces in the isolated dog forelimb. Amer. J. Physiol. 233, H136-H140. D1ANA, J. N., LONG, S. C., AND YAO, H. (1972). Effect of histamine on equivalent pore radius in capillaries of isolated dog hindlimb. Microvasc. Res. 4, 413-437. DIETZEL, W., MASSION,W. H., AND HINSHAW, L. B. (1969). The mechanism of histamine-induced transcapillary fluid movement. Pfluegers Arch. 309, 99-106. ELIASSON, E., FOLKOW, B., HILTON, S. M., OBERG, B., AND RIPPE, B. (1974). Pressure volume characteristic of the interstitial fluid space in the skeletal muscle of the cat. Acta Physiol. Scand. 90, 583-593. FLYNN, S. B., AND OWEN, D. A. A. (1977). The effects of histamine on skeletal muscle vasculature in cats. J. Physiol. 265, 795-807. GREOA, G. J., MACIEJKO,J. J., RAYMOND,R. M., AND SAK, D. P. (1980). The interrelationship among histamine, various vasoactive substances, and macromolecular permeability in the canine forelimb. Circ. Res. 46, 264-275. GUYTON, A. C. (1965). Interstitial fluid pressure. II. Pressure-volume curves of the interstitial space. Circ. Res. 16, 452-460. HADDY, F. J., SCOTT, J. B., AND GREGA, G. J. (1976). Peripheral circulation: Fluid transfer across the microvascular membrane. In "Cardiovascular Physiology II" (A. C. Guyton and A. W. Cowley, eds.), Vol. 9, pp. 63-109. Univ. Park Press, Baltimore. JOHNSON, P. C. (1965). Effect of venous pressure on mean capillary pressure and vascular resistance in the intestine. Circ. Res. 16, 294-300. KATZ, M. A. (1981). Effects of intra-arterial histamine on capillary transport properties. Clin. Res. 29, I IA. [Abstract.] KIELLMER,I., ANDODELRAM,H. (1965). The effect of some physiological vasodilators on the vascular bed of skeletal muscle. Acta Physiol. Scand. 63, 94-102. KOZLOWSKI, T., RAYMOND,R. M., KORTHUlS,R. J., WANG, C. Y., GREGA,G. J., ROBINSON,N. E., AND SCOTT, J. B. (1981). Microvascular protein efflux: Interaction of histamine & H1 receptors. Proc. Soc. Exp. Biol. Med. 166, 263-270. LANDIS, E. i . , AND PAPPENHEIMER,J. R. (1963). Exchange of substances through the capillary walls. In "Handbook of Physiology," Section 2, "Circulation," Vol. 2, pp. 961-1034. Williams & Wilkins, Baltimore. MCNAMEE, J. E., AND GROD1NS,F. S. (1975). Effect of histamine on microvasculature of isolated dog gracilis muscle. Amer. J. Physiol. 229, 119-125. PAPEENHEIMER,J. R., AND SOTO-RIVERA,A. (1948). Effective osmotic pressure of the plasma proteins and other quantities associated with the capillary circulation in the hindlimbs of cats and dogs. Amer. J. Physiol. 152, 471-491. RIPPE, B., ANDGREGA, G. J. (1978). Effects of isoprenaline and cooling on histamine induced changes in capillary permeability in the rat hindquarter vascular bed. Acta Physiol. Scand. 103, 252-262. SVENSJO, E., AND JOYNER,W. L. (1981). Microvascular permeability effects of continuous and intermittent stimulation of the hamster cheek pouch with histamine. Fed. Proc. 40, 382. [Abstract.] TIETZ, N. W. (1970). "Fundamentals of Clinical Chemistry," p. 188. Saunders, Philadelphia, Pa. VlSSCHER, M. B., HADDY, F. J., AND STEPHENS,G. (1956). The physiology and pharmacology of lung edema. Pharmacol. Rev. 8, 389-434. WADDELL, W. J. (1956). A simple ultraviolet spectrophotometric method for the determination of protein. J. Lab. Clin. Med. 48, 311-314.