[Effect of perftoran emulsion ventilation of lungs on the pulmonary surfactant system in patients with acute lung injury syndrome]. / Vplyv emul'siinoï ventyliatsiï lehen' "perftoranom" na surfaktantnu systemu lehen' u khvorykh iz syndromom hostroho lehenevoho poshkodzhennia.

The condition was studied of the pulmonary surfactant system in those patients with the syndrome of acute lung injury who had been placed on a partial emulsion ventilation of the lungs. The study of the surface tension of the endobronchial washings was made with the aid of the modified Willihelm balance before the start of the treatment and at post-treatment day 4, 6 and 8. The initial level of surface tension has been found out to be increased by 8.9%. The controlled indices were gradually returning to normal in the wake of the emulsion ventilation of the lungs. Partial emulsion ventilation of the lungs with perftoran makes for a prompt and complete restoration of surface activity of the pulmonary surfactant within 7 days. We consider it essential that a conventional intensive therapy of the acute lung injury syndrome be supplemented by partial emulsion ventilation of the lungs with perftoran.

Early gestational intra-amniotic endotoxin: lung function, surfactant, and morphometry.

We determined the effects in preterm lambs of endotoxin-induced inflammation at early gestational ages on lung function and structure and on the surfactant system. Pregnant ewes were randomized to one of five intra-amniotic endotoxin (Escherichia coli 055:B5) groups: 1 mg injected at 60 days of gestation, 1 mg at 80 days, 1 mg at 100 days, 1 mg at 60 days plus 100 days, or 0.6 mg/ day infused from Day 80 to Day 108. Control lambs received saline treatments. At 125 days, lung function was improved in all endotoxin groups. Marked increases in saturated phosphatidylcholine in lung tissue but not alveolar lavage samples were seen in all endotoxin groups except the 60- plus 100-day group. Surfactant protein mRNA and protein pool sizes were affected differently according to the timing of endotoxin treatment, but a large increase in the amount of mature surfactant protein B in alveolar lavage samples was observed in all endotoxin groups. Lung-to-body weight ratio, alveolar number, total surface area, and alveolar wall thickness were reduced by 80- to 108-day endotoxin. Intra-amniotic inflammatory stimuli in early gestation can alter pulmonary development, with the net effect of improving preterm lung function, despite changes in surfactant and lung growth that are similar to changes in the lungs of ventilated animals developing bronchopulmonary dysplasia.

[Comparative study of the effects of thymalin and vitamin E on certain indices for local pulmonary protection in rheumatoid arthritis]. / Sravnitel'noe izuchenie vliianiia timalina i tokoferola atsetat na nekotorye pokazateli mestnoi zashchity legkykh pri revmatoidnom artrite.

In experimental rheumatoid arthritis, certain indices for local defence of the lung were studied together with effects on these of preparations of vitamin E and thymalin. Noted in experimental rheumatoid arthritis are manifest changes in quantitative indices for cellular population of the bronchoalveolar space and disturbances in humoral mechanisms of defence of the lungs. The drugs employed for the treatment of the affliction have a positive effect on quantitative indices for the cell population of the lung local defence factors. But no significant effects could be demonstrated of thymalin on humoral factors of defence of the lungs. Unlike thymalin, tocopheroli acetas is noted to augment the secretion of lysozyme, to decrease the activity of phospholipase A2, to improve the surface-active properties of the lung surfactant. It is suggested that its antioxidant, membrane-stabilizing action may be responsible for the positive effect on indices for local defence of the lung.

Restoring effects of vitamin A on surfactant synthesis in nitrofen-induced congenital diaphragmatic hernia in rats.

Congenital diaphragmatic hernia (CDH) is a major cause of refractory respiratory failure in the newborn. Besides pulmonary hypoplasia, the pathophysiology of CDH also includes surfactant deficiency. Vitamin A (vit A) is important for various aspects of lung development. We hypothesized that antenatal treatment with vit A would stimulate lung surfactant synthesis in experimental CDH induced in rats by maternal ingestion of the herbicide nitrofen (2,4-dichloro-phenyl-p-nitrophenyl-ether) on Day 12. Fetuses were assigned to six experimental groups: (1) controls from rats that received olive oil, the vehicle; (2) fetuses from rats that received olive oil on Day 12 and vit A orally (15,000 IU) on Day 14; (3) nitrofen (N)-exposed fetuses without diaphragmatic hernia (N/no DH); (4) N/no DH from rats given vit A on Day 14; (5 ) nitrofen-exposed fetuses with DH (N/+DH); (6) N/+DH from rats given vit A on Day 14. Fetuses were delivered by C-section at Day 21. Lung DNA content was lowered in the nitrofen group as compared with the controls group, but increased by subsequent vit A treatment. Lung surfactant disaturated phosphatidylcholine was reduced in the N/+DH group and restored to control level by vit A. The expression level of surfactant proteins (SP) -A and -C was decreased in vit A-treated control rats and in nitrofen-exposed fetuses with or without DH. Vit A restored SP-A and -C mRNA expression to control levels in N/+DH. SP-B expression was lowered in N/no DH and increased by vit A in this group. The proportion of type II cells assessed by SP-B immunolabeling was lowered in N/+DH and restored by vit A treatment. We conclude that antenatal treatment with vit A restores lung maturation in nitrofen-induced hypoplastic lungs with CDH. These findings point out vit A as a potential therapeutical agent for correcting surfactant deficiency in CDH.

Identification of a novel DNA regulatory element in the rabbit surfactant protein B (SP-B) promoter that is a target for ATF/CREB and AP-1 transcription factors.

Surfactant protein B (SP-B) is required for the maintenance of biophysical properties and physiological function of pulmonary surfactant. SP-B is expressed in a cell/tissue-specific manner by the alveolar type II and bronchiolar (Clara) epithelial cells of the lung and is developmentally and hormonally regulated. We previously identified a minimal promoter region containing -236/+39 base pairs (bp) of rabbit SP-B gene that is necessary and sufficient for high level promoter activity in NCI-H441 cells, a cell line with characteristics of Clara cells. In this study, we have characterized the functional importance of a novel DNA regulatory element, termed SP-B CRE, with the sequence TGAGGTCA in the SP-B minimal promoter. The SP-B CRE sequence shared homology to cyclic AMP responsive element (CRE) binding sequence and contained an overlapping nuclear receptor element binding half-site. Mutation of SP-B CRE into a scrambled sequence reduced promoter activity by greater than 70%, whereas mutation into a palindromic consensus CRE increased the promoter activity by 100%. Electrophoretic mobility shift assay (EMSA) and Western immunoblot analysis of affinity purified proteins interacting with SP-B CRE showed that it is a target for binding of members of the activating transcription factor (ATF)/cyclic AMP response element binding protein (CREB) family of transcription factors, such as CREB, CREM, ATF-1, ATF-2 as well as c-Jun and TTF-1. Overexpression of CREB, ATF-2 and c-Jun inhibited SP-B promoter activity in NCI-H441 cells. These data have shown that members of the ATF/CREB family of transcription factors and c-Jun play important roles in mediating the transcriptional regulation of the SP-B gene.

Therapeutic time-window of a group IIA phospholipase A2 inhibitor in rabbit acute lung injury: correlation with lung surfactant protection.

OBJECTIVE: We attempted to determine whether group IIA secretory phospholipase A2 (sPLA2-IIA) blockade after the onset of lung injury exerted therapeutic efficacy in the treatment of oleic acid (OA)-induced acute lung injury by using S-5920/LY315920Na, a novel specific inhibitor of sPLA2-IIA, with special interest in the changes of lung surfactant. DESIGN: Prospective animal study. SETTING: University laboratory. SUBJECTS: Forty Japanese white rabbits. INTERVENTIONS: The rabbits, under anesthesia, were endotracheally intubated and mechanically ventilated and then were divided into the following groups: OA + vehicle groups, intravenous infusion of OA for the first 2 hrs (0.1 mL x kg(-1) x hr(-1)) with the addition of vehicle (1 or 2 hrs after OA administration, each n = 9, total 18 rabbits); OA + S-5920/LY315920Na groups, treated identically to the OA control with the addition of S-5920/LY315920Na (1 mg/kg bolus followed by infusion at 0.5 mg x kg(-1) x hr(-1)) after OA (1 or 2 hrs after OA administration, each n = 9, total 18 rabbits); saline control groups, treated with saline instead of OA with the addition of vehicle (1 hr after OA administration, 4 rabbits). Arterial blood gas, lung mechanics, lung inflammation, lung surfactant phospholipids, and production of inflammatory mediators in the lung were measured. MEASUREMENTS AND MAIN RESULTS: Treatment with S-5920/LY315920Na 1 hr after OA infusion, but not 2 hrs after infusion, significantly attenuated the lung injury, as estimated by hypoxemia, decreased lung compliance, pulmonary edema, and vascular permeability. The therapeutic efficacy was similar to that found in our previous pretreatment study. The treatment after 1 hr dramatically inhibited OA-induced surfactant degradation in the bronchoalveolar lavage fluid (BALF), without affecting the concentrations of thromboxane A2, leukotriene B4, and interleukin-8 in BALF. The degree of surfactant degradation in BALF paralleled well with the severity of the lung injury. Furthermore, recombinant human sPLA2-IIA reproduced the similar hydrolysis pattern of isolated surfactant in vitro, which was inhibited by S-5920/LY315920Na. CONCLUSIONS: Our results indicate that therapeutic blockade of sPLA2-IIA ameliorated lung dysfunction via protection of surfactant degradation in an animal model of acute lung injury, and they suggest a new strategy in treating clinical acute lung injury.

Glucagon-like peptide-1(7-36) amide stimulates surfactant secretion in human type II pneumocytes.

To determine the influence of glucagon-like peptides on the secretion of human pulmonary surfactant, we used human type II pneumocytes. In these cells, GLP-1(7-36) amide and exendin-4 stimulated phosphatidylcholine secretion (PC) and cAMP formation in a concentration-dependent manner; these effects were reversed by exendin(9-39). No changes were observed with other related peptides. The mechanism by which GLP-1(7-36) amide exerts its stimulatory effect was investigated with various agents that are well known to be stimulators or inhibitors of PC secretion. Thus, 8-bromo-cAMP increased and both Rp-cAMPS and H-89, the latter an inhibitor of protein kinase A (PKA), reduced pulmonary surfactant secretion in type II pneumocytes. Also, GLP-1(7-36) amide and TPA exerted additive effects in stimulating PC secretion, and Calph C, a potent inhibitor of protein kinase C (PKC), blocked most of the effect of GLP-1(7-36) amide. By contrast, both the calcium ionophore A23187 and GLP-1(7-36) amide had additive effects in increasing PC secretion, and the specific inhibitor of Ca(2+)-calmodulin-dependent protein kinase (Ca-CM-PK), KN-62, inhibited the effect of A23187 but did not alter the stimulatory action of GLP-1(7-36) amide. Our findings suggest that both PKA and PKC are involved in the stimulatory effects of GLP-1(7-36) amide on PC secretion, whereas this peptide has no effect on PC secretion through a Ca-CM-PK mechanism.

Deactivation of the pulmonary surfactant dynamics by toxic aerosols and gases.

Interactions between selected toxic aerosols and gases occurring in the air at the workplace and the pulmonary surfactant (PS) have been studied with two physicochemical techniques in vitro. The Pulsating Bubble Surfactometer (PBS) and the Langmuir-Wilhelmy Balance (LWB) have been used for measurements of dynamic interfacial properties of the PS material after its contact with several gases (sulfur dioxide, nitrogen oxides, ozone, ammonia) and liquids (sulfuric, nitric and hydrochloric acids and ammonium hydroxide), which can be brought into the alveoli with the inhaled air. Surface tension-area relationships for the interface oscillations have been analyzed using qualitative criteria of normalized hysteresis area (HA(N)) and minimum surface tension (sigma(min)). It was demonstrated that, for each analyzed compound, inactivation of the surfactant occurs, but the critical concentrations and doses are compound specific, which suggests the toxic potential of the investigated substances with respect to PS. Possible mechanisms of the interactions between the investigated substances and the surfactant components are discussed. Degradation of the PS dynamical interfacial properties (HA(N) and sigma(min)), important from the physiological viewpoint, observed in our in vitro experiments, suggests a possibility of adverse health effect in the case of a chronic inhalation of toxic gases and aerosols, even at low concentration or after a short exposure to strongly contaminated air. It results in a slowdown of the pulmonary clearance rate and increase of the lung burden for both considered cases.

Isoflurane aggravates the decrease of phosphatidycholine synthesis in alveolar type II cells induced by hydrogen peroxide.

The influence of isoflurane (Iso) on the synthesis and secretion of phosphatidylcholine (PC) of alveolar type II cells (AT II cells) injured by hydrogen peroxide (H2O2) was investigated. After primary culturing for 32 h, AT II cells isolated and purified from adult Sprague-Dawley rats were randomly divided into six groups: control group, 02.8 mM Iso group, 2.8 mM Iso group, 75 microM H2O2 group, 75 microM H2O2 + 0.28 mM Iso group, and 75 microM H202 + 2.8 mM Iso group. Synthesis and secretion of phosphatidylcholine (PC) were detected by 3H-choline chloride incorporation. It was found that 0.28 mM and 2.8 mM Iso significantly reduced PC synthesis compared with the control group (p <0.05, p <0.01, respectively), but not PC secretion. 75 microM H2O2 markedly decreased the synthesis and secretion of PC in AT II cells compared with the control group (p <0.01). 0.28 mM and 2.8 mM Iso aggravated the decrease of PC synthesis induced by H2O2 (p <0.05, p <0.01, respectively), but did not affect PC secretion. These findings suggest that Iso itself may inhibit the synthesis of PC of AT II cells in vitro and further damage the cells' function under peroxidation.

Chorioamnionitis decreased incidence of respiratory distress syndrome by elevating fetal interleukin-6 serum concentration.

Respiratory distress syndrome (RDS) of newborns is one of the most important factors determining neonatal morbidity and mortality. The interleukin-6 (IL-6) titre in cord sera of RDS-free neonates born to mothers with histological chorioamnionitis was significantly higher than that in RDS-complicated neonates without chorioamnionitis. Maternal administration of glucocorticoid suppressed the IL-6 concentrations in the cord sera of fetuses with chorioamnionitis. The fetuses without chorioamnionitis who suffered from RDS even after maternal glucocorticoid administration showed a similar IL-6 titre to that of RDS-affected neonates without chorioamnionitis. Examination of the mechanism by which IL-6 decreased the incidence of fetal RDS revealed that H441-4, a human pulmonary adenocarcinoma cell line, stimulated with recombinant (r)-IL-6 started the synthesis of mRNA and protein of pulmonary surfactant protein (SP)-A. The present study shows that IL-6 elevation in fetuses with chorioamnionitis promotes fetal lung maturation by inducing SP-A synthesis, thereby decreasing the incidence of RDS in the preterm neonates.

Effect of budesonide and salbutamol on surfactant properties.

The objective of this study was to evaluate the in vitro effect of budesonide and salbutamol on the surfactant biophysical properties. The surface-tension properties of two bovine lipid extracts [bovine lipid extract surfactant (BLES) and Survanta] and a rat lung lavage natural surfactant were evaluated in vitro by the captive bubble surfactometer. Measurements were obtained before and after the addition of a low and high concentration of budesonide and salbutamol. Whereas salbutamol had no significant effect, budesonide markedly reduced the surface-tension-lowering properties of all surfactant preparations. Surfactant adsorption (decrease in surface tension vs. time) was significantly reduced (P < 0.01) at a high budesonide concentration with BLES, both concentrations with Survanta, and a low concentration with natural surfactant. At both concentrations, budesonide reduced (P < 0.01) Survanta film stability (minimal surface vs. time at minimum bubble volume), whereas no changes were seen with BLES. The minimal surface tension obtained for all surfactant preparations was significantly higher (P < 0.01), and the percentage of film area compression required to reach minimum surface tension was significantly lower after the addition of budesonide. In conclusion, budesonide, at concentrations used therapeutically, adversely affects the surface-tension-lowering properties of surfactant. We speculate that it may have the same adverse effect on the human surfactant.

Mitochondrial glutathione replacement restores surfactant synthesis and secretion in alveolar epithelial cells of ethanol-fed rats.

BACKGROUND: Chronic alcohol abuse increases the incidence and severity of acute lung injury in critically ill patients. Previously we determined that ethanol ingestion in rats dramatically decreased alveolar epithelial cellular levels of glutathione and surfactant synthesis and secretion in vitro. Previous studies in alcoholic liver disease suggest that mitochondrial glutathione levels, and not cellular levels per se, are involved in the pathogenesis of ethanol-mediated hepatotoxicity. Therefore, we hypothesized that alveolar epithelial mitochondrial glutathione depletion mediates the observed defects in surfactant synthesis and secretion in ethanol-fed rats. METHODS: Male Sprague-Dawley rats were fed the Lieber-DeCarli liquid diet with or without ethanol (36% of total calories) for 6 weeks. In some experiments, ethanol-fed rats were then switched to the control diet for 1 week, with or without glutathione supplementation with either N-acetylcysteine (NAC) or procysteine (PRO). Alveolar epithelial type II cells were then isolated and glutathione levels (cytosolic and mitochondrial) and surfactant production (synthesis and secretion) were determined. RESULTS: Ethanol ingestion decreased (p < 0.05) mitochondrial and cytosolic levels of glutathione, and surfactant synthesis and secretion in isolated type II cells when compared to cells from control-fed rats. NAC treatment restored (p < 0.05) cytosolic but not mitochondrial glutathione levels (p > 0.05), and had no effect (p > 0.05) on surfactant synthesis and secretion in type II cells isolated from ethanol-fed rats. In contrast, PRO treatment restored (p < 0.05) cytosolic and mitochondrial glutathione levels, and normalized (p < 0.05) surfactant synthesis and secretion in type II cells isolated from ethanol-fed rats. CONCLUSIONS: These results suggest that mitochondrial, and not simply cytosolic, replacement of glutathione is necessary to improve surfactant function in critically ill patients with a history of alcohol abuse.

Self-aggregation of surfactant protein A.

Environmental factors of physiological relevance such as pH, calcium, ionic strength, and temperature can affect the state of self-aggregation of surfactant protein A (SP-A). We have studied the secondary structure of different SP-A aggregates and analyzed their fluorescence characteristics. (a) We found that self-aggregation of SP-A can be Ca(2+)-dependent. The concentration of Ca(2+) needed for half-maximal self-association (K(a)(Ca)()2+) depended on the presence of salts. Thus, at low ionic strength, K(a)(Ca)()2+ was 2.3 mM, whereas at physiological ionic strength, K(a)(Ca)()2+ was 2.35 microM. Circular dichroism and fluorescence measurements of Ca(2+)-dependent SP-A aggregates indicated that those protein aggregates formed in the absence of NaCl are structurally different from those formed in its presence. (b) We found that self-aggregation of SP-A can be pH-dependent. Self-aggregation of SP-A induced by H(+) was highly influenced by the presence of salts, which reduced the extent of self-association of the protein. The presence of both salts and Ca(2+) attenuated even more the effects of acidic media on SP-A self-aggregation. (c) We found that self-aggregation of SP-A can be temperature-dependent. At 20 degrees C, SP-A underwent self-aggregation at physiological but not at low ionic strength, in the presence of EDTA. All of these aggregates were dissociated by either adding EDTA (a), increasing the pH to neutral pH (b), or increasing the temperature to 37 degrees C (c). Dissociation of Ca(2+)-induced protein aggregates at low ionic strength was accompanied by an irreversible loss of both SP-A secondary structure and SP-A-dependent lipid aggregation properties. On the other hand, temperature-dependent experiments indicated that a structurally intact collagen-like domain was required for either Ca(2+)- or Ca(2+)/Na(+)-induced SP-A self-aggregation but not for H(+)-induced protein aggregation.

Activation of surfactant protein-B transcription: signaling through the SP-A receptor utilizing the PI3 kinase pathway.

This study describes receptor-activated signaling initiated by surfactant protein-A (SP-A), and the means by which it activates transcription of surfactant protein-B. Pulmonary surfactant is a mixture of lipids and associated proteins produced by type II pneumocytes. Interaction of SP-A with its cognate receptor (SPAR) on type II cells is involved in regulating surfactant secretion. This interaction also increases transcription of surfactant proteins and several other genes. To study SP-A cytokine activity, we used as a model surfactant-protein (SP-B) transcription, the activators of which have been characterized. HNF-3 and TTF-1 transcription factors are known to stimulate SP-B transcription. SP-A caused increased phosphorylation and nuclear localization of both. Corresponding increases in protein binding to the SP-B promoter were demonstrated by gel shift analysis. SP-A increased protein binding to HNF-3 and TTF-1 consensus recognition elements. Footprinting analysis indicated that SP-A-induced protein binding to SP-B promoter was greater in amount, but not different in location, from that seen in control cells, which normally transcribe SP-B. SP-A caused transient increases in PI3 kinase localization at the plasma membrane, and SP-A signaling to elicit increased SP-B transcription was blocked by LY294002, an inhibitor of PI3 kinase. Therefore, SP-A signals through PI3 kinase to increase SP-B transcription in type II pneumocytes by enhancing TTF-1 and HNF-3 activation of the SP-B promoter. SP-A activation of this signaling pathway, which affects many cellular functions and has not previously been implicated in type II cell transcriptional activity, has profound import for understanding type II cell biology.

Effects of eicosapentaenoic and gamma-linolenic acids (dietary lipids) on pulmonary surfactant composition and function during porcine endotoxemia.

STUDY OBJECTIVES: To investigate whether a diet enriched with fish and borage oils, with their high polyunsaturated fatty acid (PUFA) content, alters surfactant composition and function during endotoxemia. DESIGN: Prospective, randomized, blinded, controlled animal study. SETTING: Research laboratory at a medical center. PARTICIPANTS: Thirty-six 15- to 25-kg, disease-free, castrated male pigs. DIETS AND MEASUREMENTS: Three groups of pigs (n = 12 per group) were fed for 8 days diets containing either omega-6 fatty acids (FAs) (corn oil; diet A), or omega-3 FAs (fish oil; diet B), or a combination of omega-6 and omega-3 FAs (borage and fish oils; diet C). Eight of 12 pigs in each group received a 0.1-mg/kg bolus of Escherichia coli endotoxin followed by a continuous infusion (0. 075 mg/kg/h). One lung was subsequently isolated ex vivo, and pressure-volume curves were measured. The contralateral lung was lavaged, and surfactant was analyzed for total and individual phospholipids and FA composition. Minimum and maximum surface tension was measured by bubble surfactometry. RESULTS: Pigs fed either diet B or C had increased oleic acid (C(18:1) omega-9), eicosapentaenoic acid (EPA; C(20:5) omega-3), docosahexaenoic acid (C(22:6) omega-3), and total omega-3 and monounsaturated FAs in their surfactant PUFA pools. The relative percentage of linoleic acid (C(18:2) omega-6) and total omega-6 FAs were significantly lower from pigs fed diets B and C compared with diet A. Palmitic acid (C(16:0)) concentrations, the primary FA in surfactant, had a tendency to be lower in pigs fed diets B and C. There were no demonstrable effects on surfactant function or pulmonary compliance. CONCLUSIONS: Diets containing EPA or EPA and gamma-linolenic acid altered the PUFA composition of pulmonary surfactant, but without demonstrable effects on surfactant function during porcine endotoxemia.

The effects of volatile anesthetic agents on pulmonary surfactant function.

The purpose of this article is to review the findings from research directed at understanding the effects of volatile anesthetics on the respiratory surface known as pulmonary surfactant. Anesthetics have long been known to have a disruptive effect on biological membranes. This review will highlight the interactions of volatile anesthetics with pulmonary surfactant. This paper has emphasized the interaction of volatile anesthetics with the pulmonary surfactant monolayer versus the lipid bilayer. The goal of this review is to uncover to what extent this understanding has progressed in forty years. Although the goal is quite broad, the information gathered and the advice given is specific. Theories of anesthesia and surfactant structure and function are summarized and discussed in light of early physico-chemical approaches and extend to an era where powerful new three-dimensional structural techniques can be used to answer this question.

Morphologic and biochemical changes in male rat lung after surgical and pharmacological castration.

The morphology of the rat lung was studied by light microscopy in different situations: after surgical and pharmacological castration and after administration of testosterone to the castrated rat to determine if the androgen is required to maintain the normal morphology of the lung. We also determined the effect of flutamide on the phospholipid composition of both the surfactant and microsomes of the lung. Rats were separated into five groups: I - control non-castrated rats, II - castrated rats sacrificed 21 days after castration, III - castrated rats that received testosterone daily from day 2 to day 21 after castration, IV - castrated rats that received testosterone from day 15 to day 21 after castration, and V - control rats injected with flutamide for 7 days. The amount of different phospholipids in the surfactant and microsomes of the lung was measured in group I and V rats. At the light microscopy level, the surgical and pharmacological castration provoked alterations in the morphology of the lung, similar to that observed in human lung emphysema. The compositions of surfactant and microsomes of the lung were similar to those previously reported by us for the surgically castrated rats. These results indicate that androgens are necessary for the normal morphology as well as for some metabolic aspects of the lung.

Morphologic and biochemical changes in male rat lung after surgical and pharmacological castration

The morphology of the rat lung was studied by light microscopy in different situations: after surgical and pharmacological castration and after administration of testosterone to the castrated rat to determine if the androgen is required to maintain the normal morphology of the lung. We also determined the effect of flutamide on the phospholipid composition of both the surfactant and microsomes of the lung. Rats were separated into five groups: I - control non-castrated rats, II - castrated rats sacrificed 21 days after castration, III - castrated rats that received testosterone daily from day 2 to day 21 after castration, IV - castrated rats that received testosterone from day 15 to day 21 after castration, and V - control rats injected with flutamide for 7 days. The amount of different phospholipids in the surfactant and microsomes of the lung was measured in group I and V rats. At the light microscopy level, the surgical and pharmacological castration provoked alterations in the morphology of the lung, similar to that observed in human lung emphysema. The compositions of surfactant and microsomes of the lung were similar to those previously reported by us for the surgically castrated rats. These results indicate that androgens are necessary for the normal morphology as well as for some metabolic aspects of the lung.