The effects of air ions of the living mammalian trachea

Studies on the effects of air ions on the functional efficiency of the extirpated tracheal strip have been extended to the trachea of the living rabbit, rat, and mouse. Animals exposed to high mobility (+) air ions administered via a tracheotomy aperture displayed: (a) Decreased ciliary activity. (b) Decline in mucus flow rate, sometimes reversed by prolonged exposure to (+) ions; a frequent drop in the volume of mucous secretion. (c) Contraction of the membranous posterior tracheal wall. (d) Increased vulnerability to trauma of cilia and mucosal blood vessels. Similar treatment with (-) air ions reversed (+) ion effects on ciliary activity, mucus flow, contraction of the tracheal smooth muscle. Continued (-) ion treatment raised the ciliary rate (invariably) and the mucus flow rate (often) above their initial levels. (+) Air ions administered to unoperated resting mice and rats increased the respiratory rate; (-) ions reversed this effect. Long exposure of unoperated ambulatory mice to (+) air ions produced: (a) Decreased ciliary activity. (b) No clear cut effect on mucus flow. (c) Contraction of the posterior tracheal wall. (d) Increased vulnerability of the mucosa to trauma. (-) Air ions increased ciliary activity but had no clear-cut effect on the mucus flow rate.     

Parameters of gaseous ion effects on the mammalian trachea. A. Duration of effects. B. Minimal effective ion densities

A. Duration of Effects Groups of mice exposed to high densities of unipolar light air ions for 72 hours exhibited persistent alterations in the functional efficiency of their tracheas. These effects lasted at least 4 weeks, and in the case of animals treated with (+) ions included diminished ciliary activity, pale and contracted tracheal mucosa, and enhanced vulnerability to trauma. Following treatment with (-) ions, animals displayed increased ciliary activity with no other detectable changes. It required at least 60 minutes of exposure to ions to induce such "permanent" functional changes. B. Minimal Effective Ion Densities The minimal ion densities producing changes in ciliary activity within an arbitrary period of 30 minutes were determined with extirpated tracheal strips from rabbits and guinea pigs. The threshold value for (-) ions was approximately 2.5 x 10³ ions/cm.²/sec. and that for (+) ions was in the range between 1 x 10⁴ and 2.5 x 10⁵ ions/cm.²/sec.The minimal ion densities producing changes in ciliary activity within an arbitrary period of 30 minutes were determined with extirpated tracheal strips from rabbits and guinea pigs. The threshold value for (-) ions was approximately 2.5 x 10³ ions/cm.²/sec. and that for (+) ions was in the range between 1 x 10⁴ and 2.5 x 10⁵ ions/cm.²/sec. The evidence indicates that ion-induced functional changes in the ciliated epithelium of the pulmonary tree are the results of direct contact of ions with surface cells and do not involve participation of the central nervous system or circulation. So far as ciliary activity is concerned, the number of ions required to produce a change in rate is very small.     

The Biological Mechanisms of Air Ion Action : II. Negative air ion effects on the concentration and metabolism of 5-hydroxytryptamine in the mammalian respiratory tract

Negative air ions are shown to decrease 5-hydroxytryptamine concentrations in extirpated strips of rabbit trachea and in the respiratory tracts of living mice. An initial exposure of guinea pigs to (-) air ions causes a transient rise in urinary 5-hydroxyindoleacetic acid excretion which is not observed upon subsequent exposures. These findings are compatible with the hypothesis advanced earlier that (-) air ion effects depend on the ability of (-) ions to accelerate enzymatic oxidation of 5-hydroxytryptamine.     

The effect of negative air ions on the respiratory organs and blood

The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ions/cm³ inhaled by rats was studied. It was demonstrated that the inhalation of negative air ions for 60 min activated the secretion of goblet cells without impairing the tracheal mucosa and changing the protein profile of bronchoalveolar lavage. It was also found that the level of spontaneous production of reactive oxygen species by unfractionated blood cells increased after the action of negative air ions in both males and females. However, the intensity of their generation induced by opsonized zymosan increased only in females. Different sensitivities of the female and male blood antioxidant enzymes—superoxide dismutase and glutathione reductase—to negative air ions were observed. These results allow the effect of negative air ions on the respiratory organs and blood to be interpreted as priming and weak activation via a direct action on the mucosa of primary target respiratory organs and then on the blood.     

Temperature effect on the ciliary beat frequency of human nasal and tracheal ciliated cells.

Even though all human respiratory cilia are similar in structure, they experience a wide range of temperatures between the initial part of the nasal fossae which behave as heat exchangers and the inferior part of the trachea, particularly when we inhale exceedingly cold or hot air. The ciliary beat frequency of ciliated cells from human nasal mucosa and from bronchial mucosa averages 8 Hz when measured at room temperature. In the present study we compared the ciliary beat frequency of human cells from nasal and tracheal mucosa brushings at different temperatures from 5 degrees C to 50 degrees C using two different techniques, ex vivo and in vitro: ex vivo in culture medium less than 24 h after sampling and in vitro after demembranation and reactivation according to a standard procedure developed in our laboratory. Measuring the ATP-reactivated ciliary beat frequency allowed us to check the thermal parameters of the dynein ATPase and all the axonemal machinery. No significant difference in frequency was observed between nasal fossae cilia and tracheal cilia when comparing extreme temperatures in both experimental procedures.     

Effect of Pseudomonas aeruginosa rhamnolipids on mucociliary transport and ciliary beating.

Pseudomonas aeruginosa rhamnolipid causes ciliostasis and cell membrane damage to rabbit tissue, is a secretagogue in cats, and inhibits epithelial ion transport in sheep tissue. It could therefore perturb mucociliary clearance. We have investigated the effect of rhamnolipid on mucociliary transport in the anesthetized guinea pig and guinea pig and human respiratory epithelium in vitro. Application of rhamnolipid to the guinea pig tracheal mucosa reduced tracheal mucus velocity (TMV) in vivo in a dose-dependent manner: a 10-microgram bolus caused cessation of TMV without recovery; a 5-micrograms bolus reduced TMV over a period of 2 h by 22.6% (P = 0.037); a 2.5-microgram bolus caused no overall changes in TMV. The ultrastructure of guinea pig tracheal epithelium exposed to 10 micrograms of rhamnolipid in vivo was normal. Application of 1,000 micrograms/ml rhamnolipid had no effect on the ciliary beat frequency (CBF) of guinea pig tracheal rings in vitro after 30 min, but 250 micrograms/ml stopped ciliary beating after 3 h. Treatment with 100 micrograms/ml rhamnolipid caused immediate slowing of the CBF (P less than 0.01) of human nasal brushings (n = 7), which was maintained for 4 h. Mono- and dirhamnolipid had equivalent effects. The CBF of human nasal turbinate organ culture was also slowed by 100 micrograms/ml rhamnolipid, but only after 4 h (CBF test, 9.87 +/- 0.41 Hz; control, 11.48 +/- 0.27 Hz; P less than 0.05, n = 6), and there was subsequent recovery by 14 h.(ABSTRACT TRUNCATED AT 250 WORDS)     

Side specific effect of 5-hydroxytryptamine on NaCl transport in the apical and basolateral membrane of rat tracheal epithelia

5-Hydroxytryptamine (5-HT) can be released from mast cells and platelets through an IgE-dependent mechanism and may play a role in the pathogenesis of allergic bronchoconstriction. However, the effect of 5-HT on ion transport by the airway epithelium is still controversial. The objective of this study was to determine whether 5-hydroxytryptamine (5-HT) regulates NaCl transport by different mechanisms in the apical and basolateral membrane of tracheal epithelia. We studied the rat tracheal epithelium under short-circuit conditions in vitro. Short-circuit current (I(sc)) was measured in rat tracheal epithelial monolayers cultured on porous filters. 5-HT inhibited Na(+) absorption [measured via Na(+) short-circuit current (I(Na)(sc))] in the apical membrane and stimulated Cl(-) secretion [measured via Cl(-) short-circuit current (I(Cl)(sc))] in the basolateral membrane. Functional localization using selective 5-HT agonists and antagonists suggest that I(Cl)(sc)is stimulated by the basolateral membrane-resident 5-HT receptors, whereas I(Na)(sc) is inhibited by the apical membrane-resident 5-HT2 receptors. The basolateral addition of 5-HT increases intracellular cAMP content, but its apical addition does not. The addition of BAPTA/AM blocked the decrease of I(Na)(sc)which was induced by the apical addition of 5-HT, and 5-HT increased intracellular Ca concentrations. These results indicate that 5-HT differentially affects I(Na)(sc)and I(Cl)(sc)across rat tracheal monolayers through interactions with distinct receptors in the apical and the basolateral membrane. These effects may result in an increase of water movement towards the airway lumen.     

Tannic Acid Supplemented Fixation Improves Ultrastructural Evaluation of Respiratory Epithelium in Children with Recurrent Respiratory Tract Infections

Samples of the respiratory mucosa of children with recurrent respiratory infections suspected of having primary ciliary dyskinesia are routinely fixed with glutaraldehyde before ultrastructural examination. This standard technique, however, may not be optimal for visualizing ciliary components or for preserving several cellular and extracellular structures during dehydration and embedding procedures. In this study, brushes of nasal (28 samples) and/or tracheal (9 samples) mucosa from 32 children with recurrent respiratory tract infections were examined. Twenty-nine samples were fixed with glutaraldehyde supplemented with tannic acid to determine if the ultrastructural analysis of respiratory epithelium and bronchial secretions could be improved. Eight samples were conventionally fixed with glutaraldehyde alone. Lesions of the cellular membrane and damaged cells were easily visualized using tannic acid supplemented fixation. Internal ciliary structures including individual microtubules and dynein arms were also more clearly observed. In addition, the internal structure of microvilli of the respiratory epithelium could be studied and the presence of phospholipid-rich surfactant-like material within nasal and tracheal secretions were visualized after tannic acid supplemented fixation. We suggest that addition of tannic acid during fixation is useful for accurate ultrastructural evaluation of respiratory mucosa in both clinical and experimental situations.     

K(+) and Mg(2+) ions promote the self-splicing of the td intron RNA inhibited by spectinomycin

The effects of Mg(2+) and K(+) ions on the self-splicing inhibition of the td (thymidylate synthase gene) intron RNA by spectinomycin were investigated. The maximum splicing activity occurred at 20 mM KCl. The K(m) and V(max) values for GTP in the presence of 5 mM Mg(2+) are 2.25 microM and 0.55 min(-1), whereas those for GTP both in the presence of 5 mM Mg(2+) and 5 mM K(+) are 1.23 microM and 0. 46 min(-1), respectively. Spectinomycin at 10 mM concentration inhibited the splicing by about 10%, but at 20 mM concentration, the splicing rate was inhibited by about 63%. The splicing inhibition by the low concentration of spectinomycin was overcome markedly as the concentration of Mg(2+) ion was raised. At 30 mM spectinomycin, however, the splicing inhibition was not significantly affected by increasing the concentration of Mg(2+). A similar activation of the splicing rate was observed as the concentration of K(+) ion was increased. The concentration of K(+) ion required for the normal recovery of the splicing was much higher than that of Mg(2+) ion. Unlike Mg(2+) ion, 30 mM K(+) ion effectively alleviated the splicing inhibition by spectinomycin at its high concentration. The results indicate that K(+) and Mg(2+) ions may show mechanistically different interactions with spectinomycin in the self-splicing reaction of the td intron RNA.     

The effects of potassium, 5-hydroxytryptamine, adrenocorticotrophin and angiotensin II on the concentration of adenosine 3′:5′-cyclic monophosphate in suspensions of dispersed rat adrenal zona glomerulosa and zona fasciculata cells

Dispersed rat adrenal cells prepared from both the capsule and the decapsulated gland were used to investigate the effects on cyclic AMP accumulation of known stimuli of steroidogenesis [ACTH (adrenocorticotrophin), angiotensin II, K(+) ions and 5-hydroxytryptamine]. Since glomerulosa-cell preparations from capsular strippings are normally contaminated with a proportion of fasciculata cells, cells purified by fractionation on a bovine serum albumin gradient were also used. The results showed that: (1) ACTH and angiotensin II stimulated cyclic AMP accumulation in both fractionated and unfractionated zona fasciculata cells; (2) 5-hydroxytryptamine and an increased extracellular K(+) concentration (from 3.6 to 8.4mm) had no effect on cyclic AMP concentrations in fasciculata cell preparations; (3) the addition of ACTH, angiotensin II, 5-hydroxytryptamine or K(+) to the incubation medium resulted in increased cyclic AMP concentrations in unpurified zona glomerulosa cell preparations; (4) fractionation and hence the virtual elimination of fasciculata contamination, did not affect the response to 5-hydroxytryptamine and increased K(+) concentration. However, the responses to ACTH and angiotensin II were markedly lowered but not abolished. These results strongly suggest a link between cyclic AMP production and steroidogenesis in the zone of the adrenal gland that specifically secretes aldosterone. All four agents used stimulated both steroid output and cyclic AMP accumulation. However, at certain doses of 5-hydroxytryptamine, K(+) and angiotensin II the significant increases in corticosterone output were not accompanied by measurable increases in cyclic AMP accumulation.     

Assessment of the tracheal ring bioassay for detection of the cystic fibrosis serum factor

We have examined the effects of serum from cystic fibrosis patients, healthy human volunteers and from guinea pigs on ciliary activity of guinea pig tracheal ring explants after 48 hours in culture. Sera from 9 out of 10 cystic fibrosis patients produced ciliostasis. This is a significantly greater percentage than the 7 out of 21 serum samples from healthy volunteers that produced ciliostasis. Ninety-two percent of the explants in guinea pig serum had unaltered ciliary activity, illustrating the importance of intrinsic control in the bioassay design. These result suggest that the guinea pig tracheal ring bioassay may be of value as a means of identifying the presence of the ciliotoxic factor in cystic fibrosis serum for research use but is a poor discriminator for diagnostic purposes. Modification such as rinsing the tracheal mucosa with sterile medium and a new chamber for the microscopic observation of the tissue have simplified the assay.     

Structural deformation of the preterm trachea during acute distention and collapse.

The compliant airways of the premature neonate undergo episodic distention and collapse in response to changes in transmural pressure such as occur during spontaneous breathing, mechanical ventilation, and various therapeutic maneuvers. To identify and quantitate the effects of distending and collapsing transmural pressures on the structure of immature airways, tracheal segments from fetal rabbits, fixed at 0, +30, and -30 cm H2O transmural pressure, were examined using histologic and morphometric techniques. In comparison to control sections fixed at 0 cm H2O transmural pressure, application of distending pressures led to evagination of the posterior tracheal wall and significantly increased (P less than 0.05) cross-sectional area, antero-posterior diameter, circumference and muscle length, and decreased muscle thickness. Collapsed tracheal segments (-30 cm H2O) demonstrated invagination of the posterior wall and significantly (P less than 0.05) lower cross-sectional area, and antero-posterior diameter compared to the control segments; all the other parameters remained relatively unchanged. These data demonstrate extreme changes in tracheal geometry in response to the acute application of transmural pressure. From a methodological perspective, these observations suggest that fixation pressures may present significant artifact in histological analyses. Functionally, the noted deformation may lead to alterations in anatomic dead space and airway resistance, and mechanical function of the airways; all of which may compromise respiratory status in ventilated premature infant.     

Electron microprobe analysis of rabbit ciliary epithelium indicates enhanced secretion posteriorly and enhanced absorption anteriorly

The rate of aqueous humor formation sequentially across the pigmented (PE) and nonpigmented (NPE) ciliary epithelial cell layers may not be uniform over the epithelial surface. Because of the tissue's small size and complex geometry, this possibility cannot be readily tested by conventional techniques. Rabbit iris-ciliary bodies were divided, incubated, quick-frozen, cryosectioned, and freeze-dried for electron probe X-ray microanalysis of the elemental contents of the PE and NPE cells. We confirmed that preincubation with ouabain to block Na(+),K(+)-ATPase increases Na(+) and decreases K(+) contents far more anteriorly than posteriorly. The anterior and posterior regions were the iridial portion of the primary ciliary processes and the pars plicata, respectively. Following interruption of gap junctions with heptanol, ouabain produced smaller changes in anterior PE cells, possibly reflecting higher Na(+) or K(+) permeability of anterior NPE cells. Inhibiting Na(+) entry selectively with amiloride, benzamil, or dimethylamiloride reduced anterior effects of ouabain by approximately 50%. Regional dependence of net secretion was also assessed with hypotonic stress, which stimulates ciliary epithelial cell regulatory volume decrease (RVD) and net Cl(-) secretion. In contrast to ouabain's actions, the RVD was far more marked posteriorly than anteriorly. These results suggest that 1) enhanced Na(+) reabsorption anteriorly, likely through Na(+) channels and Na(+)/H(+) exchange, mediates the regional dependence of ouabain's actions; and 2) secretion may proceed primarily posteriorly, with secondary processing and reabsorption anteriorly. Stimulation of anterior reabsorption might provide a novel strategy for reducing net secretion.     

Quinone reduction by the Na+-translocating NADH dehydrogenase promotes extracellular superoxide production in Vibrio cholerae

The pathogenicity of Vibrio cholerae is influenced by sodium ions which are actively extruded from the cell by the Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR). To study the function of the Na(+)-NQR in the respiratory chain of V. cholerae, we examined the formation of organic radicals and superoxide in a wild-type strain and a mutant strain lacking the Na(+)-NQR. Upon reduction with NADH, an organic radical was detected in native membranes by electron paramagnetic resonance spectroscopy which was assigned to ubisemiquinones generated by the Na(+)-NQR. The radical concentration increased from 0.2 mM at 0.08 mM Na(+) to 0.4 mM at 14.7 mM Na(+), indicating that the concentration of the coupling cation influences the redox state of the quinone pool in V. cholerae membranes. During respiration, V. cholerae cells produced extracellular superoxide with a specific activity of 10.2 nmol min(-1) mg(-1) in the wild type compared to 3.1 nmol min(-1) mg(-1) in the NQR deletion strain. Raising the Na(+) concentration from 0.1 to 5 mM increased the rate of superoxide formation in the wild-type V. cholerae strain by at least 70%. Rates of respiratory H(2)O(2) formation by wild-type V. cholerae cells (30.9 nmol min(-1) mg(-1)) were threefold higher than rates observed with the mutant strain lacking the Na(+)-NQR (9.7 nmol min(-1) mg(-1)). Our study shows that environmental Na(+) could stimulate ubisemiquinone formation by the Na(+)-NQR and hereby enhance the production of reactive oxygen species formed during the autoxidation of reduced quinones.     

Catecholamines abolish vagal but not acetylcholine tone in the intact cat trachea

To obtain evidence in the airways that catecholamines inhibit cholinergic neurotransmission, we recorded transverse tension in the posterior wall of an upper tracheal segment in anesthetized cats and compared the inhibitory effect of stimulating cervical sympathetic nerves when segment contraction was evoked by endogenous acetylcholine (vagal tone) with the effect when contraction was evoked by exogenous acetylcholine applied directly to the mucosal surface of the tracheal segment (ACh tone). We found that sympathetic stimulation abolished all contraction evoked by vagal tone but reduced ACh tone by only one-half. In a second group of cats we compared the inhibitory effects of sympathetic stimulation and intravenous isoproterenol during vagal and ACh tone and also during tone evoked by exogenous 5-hydroxytryptamine (5-HT tone). Sympathetic stimulation or isoproterenol injection abolished all vagal and 5-HT tone but again reduced ACh tone by only one-half. Our results suggest that catecholamines released from sympathetic nerves or injected into the circulation completely inhibit vagal tone. This inhibition may be partially responsible for inducing relaxation in airway smooth muscle.     

Nipradilol induces vasodilation of canine isolated posterior ciliary artery via stimulation of the guanylyl cyclase-cGMP pathway

We examined the effect of nipradilol on contraction of the posterior ciliary artery induced by high potassium or norepinephrine and on cyclic GMP (cGMP) levels in the posterior ciliary artery of dogs. Nipradilol caused dose-dependent relaxation of KCl-and norepinephrine-induced contractions of posterior ciliary artery. The relaxant effect of nipradilol on norepinephrine-contracted ciliary artery was significantly greater than that on KCl-contracted ciliary artery. In KCl-contracted ciliary artery, N(G)-nitro-L-arginine methyl ester hydrochloride (L-NAME, 10(-4) M) did not alter the relaxant effect of nipradilol, whereas 1H-1,2,4-oxadiazolo-4,3-a-quinoxalin-1-one (ODQ, 10(-6) M) significantly inhibited this effect. Ethacrynic acid at 10(-5) M, sulfasalazine at 10(-4) M and S-decylglutathione at 10(-4) M (glutathione S-transferase inhibitors) did not inhibit the relaxant effect of nipradilol. In addition, nipradilol produced dose-dependent increases in cGMP levels in the canine posterior ciliary artery. These findings indicate that nipradilol-induced vasorelaxation in the canine posterior ciliary artery occurs via stimulation of the guanylyl cyclase-cGMP pathway.     

Functional activity of ciliated outgrowths from cultured human nasal and tracheal epithelia

Primary cultures of respiratory epithelium were produced as outgrowths from human fetal and adult tracheal and nasal polyp explants. Video recordings of the epithelial cell outgrowths were carried out after 5 days of culture and the ciliary beating frequency was analyzed by using a video technique. Uniform fields of differentiated ciliated cells were observed near the edge of the explant. In the transition region of the outgrowth from the explant to the outgrowth periphery, isolated ciliated cells were present, as well as cells with fused cilia. The ciliary beating frequency of the outgrowth of well-differentiated ciliated cells (13.5 +/- 1.4 Hz) was significantly higher (p less than 0.001) than the beating frequency of both the explant (11.9 +/- 0.7 Hz) and the ciliated cells with fused cilia (9.8 +/- 1.7 Hz). The same differentiation stages and functional activities were observed in the outgrowth cultures, whatever their origin. These in vitro models are comparable with each other and therefore could be useful for studying the ciliogenesis and functional activity of the human respiratory epithelium.     

Modulation of laryngeal and respiratory pump muscle activities with upper airway pressure and flow.

The hypothesis that upper airway (UA) pressure and flow modulate respiratory muscle activity in a respiratory phase-specific fashion was assessed in anesthetized, tracheotomized, spontaneously breathing piglets. We generated negative pressure and inspiratory flow in phase with tracheal inspiration or positive pressure and expiratory flow in phase with tracheal expiration in the isolated UA. Stimulation of UA negative pressure receptors with body temperature air resulted in a 10--15% enhancement of phasic moving-time-averaged posterior cricoarytenoid electromyographic (EMG) activity above tonic levels obtained without pressure and flow in the UA (baseline). Stimulation of UA positive pressure receptors increased phasic moving-time-averaged thyroarytenoid EMG activity above tonic levels by 45% from baseline. The same enhancement of posterior cricoarytenoid or thyroarytenoid EMG activity was observed with the addition of flow receptor stimulation with room temperature air. Tidal volume and diaphragmatic and abdominal muscle activity were unaffected by UA flow and/or pressure, whereas respiratory timing was minimally affected. We conclude that laryngeal afferents, mainly from pressure receptors, are important in modulating the respiratory activity of laryngeal muscles.     

Acute effects of parainfluenza virus on epithelial electrolyte transport

Parainfluenza viruses are important causes of respiratory disease in both children and adults. In particular, they are the major cause of the serious childhood illness croup (laryngotracheobronchitis). The infections produced by parainfluenza viruses are associated with the accumulation of ions and fluid in the respiratory tract. It is not known, however, whether this accumulation is because of a direct effect of the viruses on ion and fluid transport by the respiratory epithelium. Here we show that a model parainfluenza virus (the Sendai virus), in concentrations observed during respiratory infections, activates Cl- secretion and inhibits Na+ absorption across the tracheal epithelium. It does so by binding to a neuraminidase-insensitive glycolipid, possibly asialo-GM1, triggering the release of ATP, which then acts in an autocrine fashion on apical P2Y receptors to produce the observed changes in ion transport. These findings indicate that fluid accumulation in the respiratory tract associated with parainfluenza virus infection is attributable, at least in part, to direct effects of the virus on ion transport by the respiratory epithelium.     

Effect of negative air ions on respiratory organs and blood

The effect of negatively charged ions on respiratory organs and blood of rats has been studied. It was shown that the inhaling of negative air ions (NAI) for 60 min with a concentration of NAI at the place of location of animals 320-350 000 ions/cm2 activated the secretion of goblet cells without damaging the mucosa of the trachea and changed the spectrum of proteins of bronchopulmonary lavage. It was also found that the spontaneous production of reactive oxygen species (ROS) by cells of nonfractionated blood after the exposure to NAI increased in both males and females; the intensity of ROS generation induced by opsonized zymosan increased only in females. Different sensitivity of the antioxidant enzymes superoxide dismutase and glutathione reductase of blood to NAI in females and males was revealed. These results enable one to consider the effect of NAI as priming and a weak activation of the respiratory organs through the direct action on the mucosa of the primary target organs of the respiratory tract and then on the blood.