Traumatic shock and electroshock: the difficult relationship between anatomic pathology and psychiatry in the early 20th century.

In the conviction that a look at the past can contribute to a better understanding of the present in the field of science too, we discuss here two aspects of the relationship between early 20th century anatomic pathology and psychiatry that have received very little attention, in Italy at least. There was much debate between these two disciplines throughout the 19th century, which began to lose momentum in the early years of the 20th, with the arrival on the scene of schizophrenia (a disease histologically sine materia) in all its epidemiological relevance.The First World War also contributed to the separation between psychiatry and pathology, which unfolded in the fruitless attempts to identify a histopathological justification for the psychological trauma known as shell shock. This condition was defined at the time as a "strange disorder" with very spectacular symptoms (memory loss, trembling, hallucinations, blindness with no apparent organic cause, dysesthesias, myoclonus, bizarre postures, hemiplegia, and more), that may have found neuropathological grounds only some hundred years later.Among the doctors with a passed involvement in the conflict, Ugo Cerletti, the inventor of electroshock treatment, focused on the problem of schizophrenia without abandoning his efforts to identify its organic factors: if inducing a controlled electric shock, just like an experimentally-induced epileptic seizure, seems to allay the psychotic symptoms and heal the patient, then what happens inside the brain? In seeking histological proof of the clinical effects of electroconvulsive therapy ("the destruction of the pathological synapses"), and attempting to isolate molecules (that he called acroagonins) he believed to be synthesized by neurons exposed to strong electric stimulation, Cerletti extended a hand towards anatomic pathology, and took the first steps towards a neurochemical perspective. However his dedication to finding a microscopic explanation for schizophrenia - in the name of a "somatist" approach that, some years earlier, the psychiatrist Enrico Morselli had labelled "histomania" - was unable to prevent psychiatry from moving further and further away from anatomic pathology.

Enrico Sertoli and the supporting cells of the testis "Morphology is function".

In 1865, Enrico Sertoli, at the age of 23, published an article in his own name entitled: "About the existence of special branched cells in the seminiferous tubules of the human testis". These were Sertoli's ideal cells; in this paper he arrived at a perspicacious description of the morphology and function of these cells and in the subsequent articles he investigated the topic of spermatogenesis. Despite the importance of Sertoli's discovery, the attention of the scientific literature remained very limited after Sertoli's death for half a century and the partial eclipse finished only in the 1970s of the twentieth century.

Quality of life in long-term survivors treated for metastatic medulloblastoma with a hyperfractionated accelerated radiotherapy (HART) strategy.

PURPOSE: An intensive therapeutic strategy for metastatic medulloblastoma was launched in 1998 in our Institution. The aim of this study was to examine the long-term quality of life (QoL) in survivor patients at least 3 years after the end of the treatment. METHODS: Patients were asked to complete self-administered QoL questionnaires. An index of physical impairment (IPI) was scored (range 0-100; the lower the score the better) based on clinical objective observations. Patients were divided into two groups (lower IPI group, and higher IPI group) and descriptively compared accordingly. RESULTS: The study was completed by 25/33 eligible patients. Despite patients with a higher IPI reported worse perceived health condition, they had better emotional and psychological scores than those with a lower IPI in all QoL questionnaires. CONCLUSION: In our sample, patients with more severe objective and perceived physical impairments reported a better psychosocial QoL, possibly because the greater attention paid to them by society and family contributes to a better adjustment in long-term survivors. On this base, it should be recommended that all survivors receive a strong support as the most impaired patients.

Airway cell involvement in intermittent hypoxia-induced airway inflammation.

PURPOSE: Respiratory inflammation has been described in patients with obstructive sleep apnea syndrome, but it is unknown whether the increased neutrophil and interleukin (IL)-8 levels observed in induced sputum reflect systemic or local airway inflammation. We assessed the potential role of resident cells in intermittent hypoxia-induced airway inflammation. METHODS: Airway epithelial cells (AEC) and bronchial smooth muscle cells (BSMC) were exposed to intermittent hypoxia (IH) in vitro. Cell supernatants were assessed for matrix metalloproteinase, growth factor, and cytokine expression. The role of IH on neutrophil and BSMC migration capacities was evaluated, and the effect of supernatants from IH-exposed or control AEC was tested. RESULTS: Compared to normoxic conditions, 24 h of exposure to IH induced a significant increase of MMP-9 and MMP-2 expression and pro-MMP-9 activation (p < 0.05), and IL-8 (p < 0.05), platelet-derived growth factor (PDGF)-AA (p < 0.05), and vascular endothelial growth factor (VEGF) (p < 0.05) expression by AEC and VEGF expression (p = 0.04) by BSMC. Neutrophil chemotaxis and BSMC migration were enhanced by IH and supernatants of IH-exposed AEC (112.00 ± 4.80 versus 0.69 ± 0.43 %, p = 0.0053 and 247 ± 76 versus 21 ± 23, p = 0.009 respectively). This enhanced BSMC migration was totally abolished in the presence of an antibody blocking PDGF-AA. CONCLUSIONS: These data suggest a specific inflammatory response of airway cells to IH, independently of systemic events.

[Firearms related suicide/homicide rate among the security guards population in Italy]. / Suicidi e omicidi con l'arma di ordinanza. Analisi della casistica nelle guardie particolari giurate in Italia.

OBJECTIVE: The main aim of this study is evaluating the suicide/homicide rate of the Italian security guards population compared to other armed and general populations during a recent period. METHODS: The authors reviewed the incidence of suicides and homicides among security guards from 1996 to 2006 and, where information was available, a comparison was made with Italian population adapted by age. Comparisons with the general population were also made. RESULTS: The average rate of firearms related suicide among the security guards population during the established period was 11.7 per 100,000 persons-years (95% CI = 6.6-16.7) compared to a guns-related suicide rate of 0.7 per 100,000 person-years, (95% CI = 0.6-0.7) and a non-guns related rate of 5.5 per 100,000 persons-years, (95% CI = 5.2-5.9) for the general population adjusted for age. The overall homicide rate among security guards during the period was 11.4 per 100,000 person-years (95% CI = 6.2-15.4) compared with the homicide rate for the Italian population of 5.4 per 100,000 persons-years, (95% CI = 7.3-15.4). CONCLUSION: The rate of suicide and homicide among the Italian security guards population was higher than the suicide/homicide rate in the general population. These results show that the phenomenon we have described needs attention and specific prevention activities.

Pathologica in the time of "Spanish flu".

The pandemic "Spanish flu", that in a few weeks of the autumn 1918 caused in Italy a number of deaths between 350.000 and 600.000, was widely discussed by the scientific community, although very little of that debate leaked out, because of the military censorship.In the present article we comment on the original papers describing the hemorrhagic pneumonia, and on discussions about the ideas of the origin of the pandemic infection (Pfeiffer bacillus, vs streptococcus or other bacteria vs a "viral hypotesis") that occurred in Pathologica during and soon after that ominous pandemia.

Water load test before and after PPI therapy in patients with gastro-oesophageal reflux disease.

BACKGROUND: Patients with gastro-oesophageal reflux disease may complain of epigastric pain, bloating, early satiety, epigastric fullness, epigastric burning, nausea and vomiting. AIMS: To evaluate the symptoms in response to gastric distension and its relationship to a therapeutic course in patients with gastro-oesophageal reflux disease using the water load test, compared to healthy controls. METHODS: Thirty gastro-oesophageal reflux disease patients with grade A oesophagitis (studied before and after 4 weeks of therapy with esomeprazole, 40 mg per day) and 15 patients with reflux-related symptoms demonstrated at wireless pH monitoring (non-erosive reflux disease) were compared to 30 healthy volunteers. RESULTS: Patients with grade A oesophagitis and with reflux-related symptoms ingested significantly lower water volumes than did controls, before onset of fullness, without statistically significant difference between erosive or non-erosive gastro-oesophageal reflux disease; this variable improved in patients after treatment. Nausea scores were higher basally in patients, pre- and post-therapy, and improved after therapy. Thirty-minute fullness and bloating scores improved after therapy in all gastro-oesophageal reflux disease patients compared to controls and pre-therapy. In all pre-treatment patients, a significant correlation was found only with epigastric fullness; after treatment, there was no significant relationship between the water load and the symptom scores. CONCLUSIONS: In patients with reflux-related symptoms, with or without grade A oesophagitis, the water load test is frequently abnormal, suggesting an altered gastric function. This could explain the incomplete resolution of symptoms after treatment in some patients, and should lead to additional studies aimed at exploring gastric function in gastro-oesophageal reflux disease patients.

Phenomenology and emotional impact of neuropsychiatric symptoms in orthotopic liver transplant for hepatocellular carcinoma.

BACKGROUND: Few studies have focused on neuropsychiatric symptoms like hallucinations or delusions occurring in the early posttransplant period. The aim of this study was to estimate the percentage of patients reporting neuropsychiatric symptoms in the immediate postoperative phase, to describe the phenomenology, and to evaluate the emotional impact of such disorders. METHOD: We studied 94 consecutive patients who underwent orthotopic liver transplant (OLT) for hepatocellular carcinoma at least 30 days prior. The presence of neuropsychiatric symptoms were retrospectively evaluated through a semistructured interview. RESULTS: Overall 49 patients (52%) reported various postoperative neuropsychiatric symptoms. None of the demographic and clinical variables showed significant associations, except for barbiturate administration; patients using barbiturates showed a lower percentage of neuropsychiatric symptoms. It was a time-limited phenomenon that in most cases resolved by day 7 after transplantation. Interestingly, the most frequent emotion perceived was surprise and not fear; a nontrivial amount of patients reported happiness, while many patients reported no emotion. CONCLUSIONS: The results of this study suggested the usefulness of a registry of the neurological and psychiatric complications after OLT that may help to clarify the pathogenic mechanisms of such complications and implement uniform protocols of prevention and treatment. In fact, better knowledge of the phenomenology of neuropsychiatric symptoms in OLT recipients could allow easier symptom recognition and therapy adjustments on the basis of the emotional impact of such symptoms on patients, family, and caregivers, as well as increase patients' awareness and capability to face this experience.

Colon and gastric metastases from a primary signet-ring cell carcinoma of the urinary bladder.

Signet-ring cell carcinoma is a relatively rare neoplasm that rarely occurs in the urinary bladder. We report a case of a 60-year-old man who presented with gross haematuria. Cystoscopy revealed a white sessile tumour of the anterior bladder wall. The histological diagnosis showed a primary signet-ring cell carcinoma of the bladder (T3bN0M0). Eighteen months after radical cystectomy, the patient developed colon and stomach metastases. This case represents the first description of a primary signet-ring cell carcinoma of the urinary bladder with gastrointestinal metastases.

Evidence for a sodium-dependent sugar transport in rat tracheal epithelium.

The presence of Na(+)-coupled sugar transport in rat trachea was investigated using the nonmetabolizable glucose analogs methyl alpha-glucopyranoside and 3-O-methylglucose. The rates of disappearance from tracheal instillates and the tissue uptake of these analogs were compared with those of L-glucose. Experiments were performed in vivo, using a cross-circulation preparation, and in vitro, on tracheal strips. The analog methyl alpha-glucopyranoside was removed in vivo from the tracheal lumen faster than L-glucose. The cellular uptake in vivo or in vitro was determined by lysing the cells lining the tracheal lumen with detergents. This uptake was inhibited by luminal glucose, phloridzin and Na+ substitution with choline. The transport rate of 3-O-methylglucose was very low and thus discouraged inhibition experiments. These results indicate the presence of a Na+/sugar cotransport system in rat trachea. The effects of luminal interactions suggest that the cotransport is located in the apical membrane of the tracheal epithelium. It resembles that previously described in the rat alveolar epithelium, but apparently differs from that found in the fetal sheep lung in which a significant 3-O-methylglucose cotransport with Na+ has been described.

Sodium-dependent phosphate and alanine transports but sodium-independent hexose transport in type II alveolar epithelial cells in primary culture.

Inorganic phosphate, amino acids and sugars are of obvious importance in lung metabolism. We investigated sodium-coupled transports with these organic and inorganic substrates in type II alveolar epithelial cells from adult rat after one day in culture. Alveolar type II cells actively transported inorganic phosphate and alanine, a neutral amino acid, by sodium-dependent processes. Cellular uptakes of phosphate and alanine were decreased by about 80% by external sodium substitution, inhibited by ouabain (30 and 41%, respectively) and displayed saturable kinetics. Two sodium-phosphate cotransport systems were characterized: a high-affinity one (apparent Km = 18 microM) with a Vmax of 13.5 nmol/mg protein per 10 min and a low-affinity one (apparent Km = 126 microM) with a Vmax of 22.5 nmol/mg protein per 10 min. Alanine transport had an apparent Km of 87.9 microM and a Vmax of 43.5 nmol/mg protein per 10 min. By contrast, cultured alveolar type II cells did not express sodium-dependent hexose transport. Increasing time in culture decreased Vmax values of the two phosphate transport systems on day 4 while sodium-dependent alanine uptake was unchanged. This study demonstrated the existence of sodium-dependent phosphate and amino acid transports in alveolar type II cells similar to those documented in other epithelial cell types. These sodium-coupled transports provide a potent mechanism for phosphate and amino acid absorption and are likely to play a role in substrate availability for cellular metabolism and in regulating the composition of the alveolar subphase. The decrease in phosphate uptake with time in culture is parallel to decrease in surfactant synthesis reported in cultured alveolar type II cells, suggesting that phosphate availability for surfactant synthesis may be accomplished by a sodium-dependent phosphate uptake.

Nutritional state and energy balance in cirrhotic patients with or without hypermetabolism. Multicentre prospective study by the 'Nutritional Problems in Gastroenterology' Section of the Italian Society of Gastroenterology (SIGE).

BACKGROUND AND AIMS: A total of 334 stable, compensated cirrhotic patients admitted to 10 Italian Gastroenterology Units were included in a prospective study to evaluate nutritional state and energy balance in liver cirrhosis. MATERIALS AND METHODS: Nutritional state and calorie intake were examined in the total population, while adequacy of calorie intake versus measured total energy expenditure was evaluated in a comparable subpopulation and in 40 matched controls, by computing the energy balance. RESULTS: Our data demonstrated that: (i) malnutrition was present in 25% of the total patients and significantly correlated with the Child's group (A=16%; B=25%; C=44%); (ii) the type of malnutrition is influenced by mBEE: normometabolic patients exhibit a significant (p<0.005) reduction of mid-arm fat area while both hypermetabolic and hypometabolic patients show a significant (p<0.005) decline in kg of free fat mass; (iii) normometabolic and hypometabolic patients have a negative energy balance, due to a high level of physical activity (127+/-14 kJ) in the first group and a reduced energy intake/kg body weight (102+/-12 kJ) in the second; (iv) hypermetabolic patients have a positive energy balance due to decreased daily physical activity/kg body weight (108+/-28 kJ); (v) malnourished and normometabolic patients eat a significantly (p<0.05) reduced percentage of protein whereas malnourished and hypermetabolic patients eat a significantly increased percentage of fat (p<0.05). CONCLUSION: Although multivariate regression analysis confirms that the Child-Pugh's score is a better independent predictor of malnutrition, the measure of REE, TEE, calorie intake and energy balance need to be routinely performed in cirrhotic patients, in order to recognise hypermetabolic and hypometabolic patients (approximately 30%) in whom the nutritional and metabolic parameters are indispensable as a basis for designing and prescribing personalised nutritional strategies that can treat muscle malnutrition and thus improve the morbidity and mortality rates.

Dying after cure: A case of suicide in an adolescent treated for cancer.

Although suicide among childhood cancer survivors is rare, there is still a significantly higher risk in this population than in healthy adolescents. A 17-year-old girl cured of Burkitt lymphoma committed suicide after completing her treatment. She had never previously shown signs of psychological suffering and was in good general health. This case made the operators wonder how this tragic possibility might be prevented. It is essential for the ongoing monitoring of the psychological and social suffering of young people during follow-up programs to be assured by a multidisciplinary team involved in the patient's global care.

Brush-border-enzyme-mediated intestine-specific drug delivery. Amino acid prodrugs of 5-aminosalicylic acid.

5-Aminosalicylic acid (5-ASA) is the active principle of a number of preparations aimed at the treatment of inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis, but its efficacy is limited by early absorption and metabolism. The possibility to exploit the selective hydrolytic activity of brush border enzymes such as aminopeptidase A and carboxypeptidases was studied by preparing the following four amino acid prodrugs of 5-ASA: 5-(N-L-aspartylamino)-2-salicylic acid, disodium salt (18), 5-(N-L-glutamylamino)-2-salicylic acid, disodium salt (19), [(5-aminosalicyl)-L-prolyl]-L-leucine, sodium salt (25), and [[5-(N-L-glutamylamino)salicyl]-L-prolyl]-L-leucine, disodium salt (28). In these compounds, the peptide bond is selectively split by the intestinal brush border aminopeptidase A (compounds 18, 19, and 28) and carboxypeptidases (compounds 25 and 28).

Effects of rilmenidine on bronchomotor responses in the guinea pig.

This study compares the effects of 2 alpha 2-adrenergic agonists, rilmenidine (S 3341) and clonidine, on histamine-induced bronchoconstriction (HIB) in guinea pigs. Clonidine has previously been shown to potentiate HIB in guinea pigs. The study was conducted in anesthetized, paralyzed and ventilated guinea pigs. Six groups of at least 6 guinea pigs were pretreated with saline, rilmenidine (0.1, 0.3 and 1 mg/kg intravenously) or clonidine (0.01 and 0.03 mg/kg intravenously), respectively. Conductance, dynamic compliance and static compliance of the respiratory system were measured before and during histamine infusion (80 ng/kg/s) and expressed as percent variation. Clonidine potentiated HIB as previously reported. In contrast, rilmenidine potentiated HIB only at the dose of 1 mg/kg. As it is well known that HIB is influenced by adrenergic outflow, these results suggest that rilmenidine has less inhibitory effect than clonidine on adrenal secretion.

Failure of enhancement by labetalol of bronchopulmonary effects of histamine in guinea-pigs: independence of alpha-adrenoceptor antagonism.

The effect of labetalol on histamine-induced bronchoconstriction was studied in anaesthetized guinea-pigs. Unlike propranolol (1 mg kg-1), the same dose of labetalol did not enhance histamine-induced bronchoconstriction. To determine whether the absence of enhancement of the respiratory effects of histamine by labetalol was due to its alpha 1-blocking properties or to its partial agonist activity at beta 2-adrenoceptors, the effects of propranolol plus prazosin and of propranolol plus labetalol on histamine-induced bronchoconstriction were examined. In both cases, the bronchoconstrictor effects of histamine were enhanced to the same extent as with propranolol alone. These data support the hypothesis that the non impairment of respiratory mechanics by labetalol is not due to antagonism at alpha-adrenoceptors and may be mediated by its partial agonist activity at beta 2-adrenoceptors.

A possible role for the cortisol/anticortisols imbalance in the progression of human immunodeficiency virus.

The progression of HIV infection is accompanied by complex alterations in the production of adrenal steroids. Cortisol levels are increased in HIV infection whereas those of dehydroepiandrosterone (DHEA), a physiologic antagonist of the immunoregulatory activities of cortisol, decrease. The progression of HIV infection to AIDS is also characterised by a shift from a type 1 to type 2 cytokine production. Thus, defective production of interferon gamma (IFN gamma), interleukin (IL)-2, and IL-12 as well as increased production of IL-4, IL-5, IL-6, and IL-10 are observed in HIV-seropositive individuals and are proposed to be in vitro immunologic marker of progression. Cortisol and pharmacological doses of glucocorticoids (GC) suppress IL-2 and IFN gamma production and favour the production of IL-4. Furthermore, GC and IL-4 stimulate the differentiation of B lymphocytes into IgE producing plasma cells, the concentration of which augments in HIV infection. Finally, GC induce programmed cell death (PCD) in a variety of different cells, including mature T lymphocytes, and type 2 cytokines were recently proposed to augment the susceptibility of T lymphocytes to PCD. It was suggested that the progressive shift from type 1 to type 2 cytokine production characteristic of HIV infection could be at least partially provoked by the increase in the production of cortisol and the reduction of DHEA. This hypothesis is discussed within the scenario of an endrocrinologic imbalance being responsible for HIV progression at least partially via increased susceptibility of HIV + CD4 lymphocyte to PCD.

Airway obstruction in bronchial sarcoidosis: outcome with treatment.

STUDY OBJECTIVE: Airway obstruction (AO) in sarcoidosis is reported to be associated with respiratory symptoms, increased morbidity, and an increased mortality risk. Because AO in sarcoidosis may result from several causes, the therapeutic benefit of corticosteroids is difficult to determine. The aim of this study was to evaluate the therapeutic response of AO attributable to sarcoid granulomas in the bronchial wall. PATIENTS: We selected 11 patients who had sarcoidosis with AO (defined as FEV(1)/vital capacity [VC] < 70%) associated with sarcoid granulomas on an endobronchial biopsy. Exclusion criteria were history of asthma, smoker or ex-smoker, stage 4 disease, evidence of extrinsic compression by enlarged lymph nodes, and localized endobronchial stenosis seen during fiberoptic bronchoscopy. INTERVENTIONS: We compared the results of pulmonary function tests and clinical, radiologic, and biological findings at baseline with those obtained at the time of the last pulmonary function tests available, between the sixth and 12th months of treatment. Eight patients took oral corticosteroids (20 to 60 mg/d initially), one received IV methylprednisolone pulses, another took oral hydroxychloroquine, and the last one received IM methotrexate. MEASUREMENTS AND RESULTS: With treatment, FEV(1) and FEV(1)/VC significantly improved in eight patients (72%), normalized in four patients, and was unchanged in the remaining three patients. The mean FEV(1) increased from 60.8 +/- 10.8% to 76 +/- 13.7% of the predicted value (p < 0.02). VC did not change significantly. FEV(1)/VC increased from 76.1 +/- 6.4% to 87.6 +/- 10.7% of the predicted value (p < 0.01). Dyspnea on exertion and other clinical findings were attenuated in 10 patients; the chest radiograph improved in 9 patients, and normalized in 5 patients. The mean serum angiotensin-converting enzyme level decreased from 112 +/- 48 to 58 +/- 40 IU/mL (p < 0.05), and normalized in four patients. CONCLUSION: The present study indicates that AO caused by sarcoid granulomas in the bronchial wall can be either partially or completely reversed by treatment with a concomitant attenuation of pulmonary symptoms.

Hypoxia regulates gene expression of alveolar epithelial transport proteins.

Alveolar hypoxia occurs during ascent to high altitude but is also commonly observed in many acute and chronic pulmonary disorders. The alveolar epithelium is directly exposed to decreases in O(2) tension, but a few studies have evaluated the effects of hypoxia on alveolar cell function. The alveolar epithelium consists of two cell types: large, flat, squamous alveolar type I and cuboidal type II (ATII). ATII cells are more numerous and have a number of critical functions, including transporting ions and substrates required for many physiological processes. ATII cells express 1) membrane proteins used for supplying substrates required for cell metabolism and 2) ion transport proteins such as Na(+) channels and Na(+)-K(+)-ATPase, which are involved in the vectorial transport of Na(+) from the alveolar to interstitial spaces and therefore drive the resorption of alveolar fluid. This brief review focuses on gene expression regulation of glucose transporters and Na(+) transport proteins by hypoxia in alveolar epithelial cells. Cells exposed to severe hypoxia (0% or 3% O(2)) for 24 h upregulate the activity and expression of the glucose transporter GLUT-1, resulting in preservation of ATP content. Hypoxia-induced increases in GLUT-1 mRNA levels are due to O(2) deprivation and inhibition of oxidative phosphorylation. This regulation occurs at the transcriptional level through activation of a hypoxia-inducible factor. In contrast, hypoxia downregulates expression and activity of Na(+) channels and Na(+)-K(+)-ATPase in cultured alveolar epithelial cells. Hypoxia induces time- and concentration-dependent decreases of alpha-, beta-, and gamma-subunits of epithelial Na(+) channel mRNA and beta(1)- and alpha(1)-subunits of Na(+)-K(+)-ATPase, effects that are completely reversed after reoxygenation. The mechanisms by which O(2) deprivation regulates gene expression of Na(+) transport proteins are not fully elucidated but likely involve the redox status of the cell. Thus hypoxia regulates gene expression of transport proteins in cultured alveolar epithelial type II cells differently, preserving ATP content.

Cholinergic component of histamine-induced bronchoconstriction in newborn guinea pigs.

The magnitude of parasympathetic reflex-mediated bronchoconstriction during histamine infusion was compared in anesthetized paralyzed newborn and adult guinea pigs. The animals were ventilated using a constant-flow ventilator, and the conductance and compliance of the respiratory system were continuously monitored. We found that reactivity to histamine infusion was less in newborns than in adults, because newborns required a larger dose of histamine than adults (300 vs. 125 ng.kg-1.s-1) to produce an equivalent decrease in conductance (42 +/- 13 vs. 42 +/- 15%). Vagal interruption by bilateral cervical vagotomy or muscarinic blockade with atropine (3 mg/kg) significantly reduced the bronchoconstrictor response to histamine in adults. By contrast, neither vagotomy nor atropine significantly changed this response in the newborns. These results indicate the lack of a vagal component in the bronchoconstriction that histamine induced in the newborns. Their relative unresponsiveness to histamine might partly be related to the fact that, in the newborn, histamine mainly acts directly via its airway receptors.