[Three siblings with interstitial pneumonia]

Patient 1: A 64-year-old woman was admitted for further examination after reticulonodular shadows were found on a chest X-ray film. Idiopathic interstitial pneumonia (IIP) was diagnosed. Patient 2: The 60-year-old sister of patient 1 was admitted for further examination after reticulonodular shadows were found on a chest X-ray film. IIP was diagnosed. About half a year later, her proximal interphalangeal joints had become swollen and the result of a rheumatoid hemagglutination test was positive. Therefore, the pneumonia was suspected to have been caused by a collagen-vascular disease (CVD), rheumatoid arthritis. Patient 3: The 64-year-old brother of patient 1 was examined. A chest X-ray film revealed reticulonodular shadows that were strongly suggestive of IIP. The remaining three siblings were examined. In a 62-year-old sister, the chest X-ray film was normal, but the level of anti-nuclear antigen was elevated. The fact that the level of this antigen was high in these four siblings and that the 60-year-old sister later suffered from rheumatoid arthritis suggested the presence of a factor predisposing to CVD in these siblings. The interstitial pneumonia in these siblings may have been related to CVD.

[Pulmonary nitric oxide synthase isoform expression and their functional significance]

Nitric oxide (NO), discovered as an endothelium derived relaxing factor, is generated during conversion of L-arginine to L-citrulin by nitric oxide synthase (NOS). Now, genes for three isoforms of NOS (nNOS, eNOS, and iNOS) have been cloned and pulmonary expressions of these NOS isoforms have been studied extensively. Localization of these NOS isoforms in the lung and their functional roles are discussed.

[Idiopathic interstitial pneumonia and TNF gene restriction fragment length polymorphism]

Tumor necrosis factor alpha (TNF alpha) and lymphotoxin (TNF beta) are cytokines with numerous similar immunoregulatory effects. In pulmonary fibrosis, TNF alpha/beta appears to play a critical role in the regulation of the fibroproliferative response. The human TNF alpha/beta genes are located between the HLA-B and the HLA-DR region. In man 5.5 kb and 10.5 kb of TNF alpha/beta restriction fragment length polymorphic (RFLP) bands have recently been identified by means of enzyme NcoI. TNF alpha/beta production is reported to be correlated to the NcoI RFLP. In some collagen diseases, a decreasing frequency of the 10.5 kb band is reported. The two allele NcoI RFLP of the TNF alpha region, yielding bands of 5.5 kb and 10.5 kb, was investigated in normal Japanese subjects and patients with IIP. The frequency of these bands was not different between normal subjects and patients with IIP. However, in female patients, the frequency of the 5.5 kb band was significantly increased compared with those in the male patients and normal subjects. The increase of this band may have some relation to the pathogenesis of idiopathic interstitial pneumonia.

Nitrooxy alkyl apovincaminate modulates GABA(A) receptor in rat neocortical neurones

We investigated the effects of VA-045 ((+)-eburnamenine-14 carboxylic acid (2-nitroxyethyl) ester) on GABA(A) receptor-mediated Cl- currents in dissociated rat cerebral cortical neurones, using a nystatin-perforated patch recording configuration. At a holding potential of - 40mV, the external application of GABA evoked an inward Cl- current with an EC50 value of 5.6 x 10(-6)M. VA-045 increased the GABA response at GABA concentrations below 3.0 x 10(-6)M. The GABA response showed a time dependent decay consisting of fast and slow components and VA-045 significantly accelerated both components. The site of action for VA-045 was considered to be different from that for benzodiazepines or barbiturates.

Mechanisms of epidermal growth factor-induced contraction of guinea pig airways

We investigated the functional effects of epidermal growth factor (EGF) on guinea pig airways in vitro. EGF (3 ng/ml to 1 microgram/ml) induced a concentration-dependent contraction in epithelium-denuded strips. The average maximal contraction was 0.64 +/- 0.1 g (mean +/- S.E., for n = 27), which was 72.0 +/- 9.5% of the 100 mM KCl-induced contraction. The EC50 was 12.3 +/- 1.6 ng/ml. The presence of the epithelium significantly suppressed the EGF-induced contraction (P < 0.01). EGF-induced contraction was abolished by cyclooxygenase inhibitors (indomethacin and ibuprofen) and a 5-lipoxygenase inhibitor, 2-(12-hydroxydodeca-5,10-diynyl)-3,5,6-trimethyl-1,4-benz oqu inone (AA-861). It was also inhibited by a leukotriene-receptor antagonist, 8-[p-(4-phenylbutyloxy)benzoyl]amino-2-(tetrazol-5-yl)-4-oxo -4H-1-benzopyran hemihydrate (ONO-1078) but not affected by a thromboxane A2-synthetase inhibitor, (E)-3-[4-(1-imidazolylmethyl)phenyl]-2-propenoic acid (OKY-046) or a thromboxane A2-receptor antagonist, 9,11-epithio-11,12-methano-thromboxane A2 (ONO-3708). A phospholipase A2 inhibitor (mepacrine) inhibited the EGF-induced contraction but a diacylglycerol-lipase inhibitor, 1,6-di-(O-(carbamoyl)cyclohexanone oxime)hexane (U-57908) and a phospholipase D inhibitor (wortmannin) did not affect it. A tyrosine kinase inhibitor (genistein) abolished it. Measurement of prostanoids showed that EGF (300 ng/ml) did not increase the prostaglandin F2 alpha level in either epithelium-intact or epithelium-denuded strips. In epithelium-intact strips, EGF significantly increased the prostaglandin E2 concentration (P < 0.01). These results suggest that EGF causes contraction of guinea pig airway smooth muscle by activating tyrosine kinase followed by phospholipase A2 activation, and that arachidonic acid metabolites, especially leukotrienes, may have important roles in this contraction.

Seasonal variation in blood pressure in normotensive women studied by home measurements

1. The factors influencing the seasonal variation in blood pressure measured at home in normotensive women were examined. 2. Sixteen female subjects (56.3 +/- 7.9 years old, mean +/- SD) measured their blood pressure and pulse rate at home each morning for more than 20 times per month for at least 1.5 years. Blood pressure and body weight were also determined in the office once or twice a month in that period. Monthly means of outdoor and indoor temperatures and daytime length were obtained from the Meteorological Observatory. The single cosinor method was used to evaluate circannual rhythm. 3. We observed a biphasic seasonal variation in self-recorded blood pressure measured at home, environmental temperature and daytime length but found no apparent seasonal variation in body weight and blood pressure measured in the office. The lowest levels of systolic and diastolic blood pressure measured at home were observed in July. The longest daytime length was recorded in June, while the highest outdoor temperature and indoor temperature were recorded in August, indicating that the longest daytime length preceded and the highest environmental temperature lagged behind the lowest level of blood pressure. The shortest daytime length is in December. The lowest outdoor and indoor temperature were observed in January, while the highest levels of self-recorded systolic blood pressure and diastolic blood pressure were in January and December, respectively. Half-amplitudes of self-recorded systolic and diastolic blood pressure were 2.6 +/- 1.0 mmHg and 2.0 +/- 0.8 mmHg, respectively. 4. These findings indicate the importance of a seasonal effect, i.e. daytime length and the environmental temperature, on the blood pressure of individuals.

Role of vasopressin in neurocardiogenic responses to hemorrhage in conscious rats

Vasovagal reflexes, such as hypotension and bradycardia, are induced by rapid hemorrhage and mimic neurocardiogenic reflexes in mammals. We examined the role of vasopressin in the neurocardiogenic responses to mild, rapid hemorrhage (1 mL/100 g for 30 seconds) and severe hemorrhage (1 mL/100 g body wt for 30 seconds repeated three times at 11-minute intervals) in homozygous Brattleboro and Long-Evans rats. Mild, rapid hemorrhage induced severe bradycardia and hypotension only in Long-Evans rats. Exogenous vasopressin (1.85 pmol/kg per minute for 1 hour) restored both the bradycardic and hypotensive responses in Brattleboro rats. DDAVP, a vasopressin V2-receptor agonist (0.19 pmol/kg per minute for 24 hours), did not affect the cardiovascular responses to hemorrhage in Brattleboro rats, although it maintained urine production within normal limits. However, OPC-31260 (21.6 mumol/kg IV), a vasopressin V2-receptor antagonist, attenuated both the hypotensive and bradycardic responses to hemorrhage in Long-Evans rats. A vasopressin V1-receptor antagonist attenuated bradycardia and delayed the recovery of arterial pressure after hemorrhage but did not affect the hypotension that occurred immediately after hemorrhage in Long-Evans rats. Methylatropine also attenuated both the bradycardic and hypotensive responses induced by hemorrhage, but propranolol had no effect on the cardiovascular responses to hemorrhage in Long-Evans rats. The recovery of arterial pressure after repeated hemorrhage was less adequate in Brattleboro rats than in Long-Evans rats. Our results suggest that the neurocardiogenic responses to hemorrhage, especially hypotension, may be related to vasodilation induced by a V2-receptor-mediated mechanism and by the vagal reflex, both of which are substantiated by the existence of vasopressin. The coexistence of V1- and V2-receptor mechanisms may be necessary for the hypotensive response to hemorrhage. We found that a V2-receptor antagonist attenuated the hypotension mediated by the so-called neurocardiogenic reflex.

Dual mechanisms of GABAA response inhibition by beta-lactam antibiotics in the pyramidal neurones of the rat cerebral cortex

1. The effects of beta-lactam antibiotics on the gamma-aminobutyric acid (GABA)-induced Cl- current were investigated in pyramidal neurones freshly dissociated from the rat frontal cortex by the use of a nystatin-perforated patch recording mode under voltage-clamp conditions. 2. The GABA-induced inward current increased in a concentration-dependent manner with an EC50 of 6.7 x 10(-6) M at a holding potential of -40 mV. The GABA response was accompanied by an increase in the membrane conductance and reversed at near the Cl- equilibrium potential. 3. All beta-lactams (penicillin, imipenem, aztreonam and cefotiam) inhibited the 10(-5) M GABA-induced response in a concentration-dependent manner with an IC50 and Hill coefficient of 1.3 x 10(-3) M and 0.64 for penicillin, 9.6 x 10(-4) M and 0.83 for imipenem, 2.5 x 10(-3) M and 9.99 for aztreonam, and 2.9 x 10(-4) M and 1.03 for cefotiam. 4. Imipenem inhibited the GABA-response competitively while penicillin inhibited the same response in a noncompetitive fashion. 5. The inhibitory action of imipenem showed no voltage-dependency, whereas the effect of penicillin was voltage-dependent. 6. It is thus proposed that some classes of beta-lactams, including imipenem may have a mechanism that is different from penicillin and competitively affects the GABAA receptor.

Increased gain in baroreceptor-heart rate reflex in patients with primary aldosteronism

OBJECTIVE

Reduced baroreflex sensitivity has been reported in several kinds of human hypertension. However, the nature of the baroreceptor-heart rate reflex in hypertension due to excess mineralocorticoid has never been fully explored.

PATIENTS AND METHODS

Thirty patients with primary aldosteronism, 60 patients with essential hypertension (World Health organization stages I or II) and 45 normotensive subjects were enrolled. The groups did not differ in mean age. Blood pressure was similar between patients with primary aldosteronism and those with essential hypertension. Blood pressure (Finapres) and the RR interval (ECG) were monitored continuously at rest. The closed loop gain between systolic blood pressure and RR interval variabilities was used to measure the sensitivity of the baroreceptor-heart rate reflex.

RESULTS

Baroreflex sensitivity in the group with primary aldosteronism was significantly greater than in the essential hypertensive group, but did not differ significantly between the group with aldosteronism and the normotensive group. Three to four weeks after removal of an adrenal adenoma (n = 25), both systolic and diastolic blood pressure were decreased significantly in the aldosteronism group but were still higher than in the normotensive group. The baroreflex sensitivity was reduced by about 40% after adrenalectomy compared to pre-operative values. The decrease in the baroreflex gain following adrenalectomy was correlated negatively with the decrease in systolic blood pressure (r = -4.00, P=0.05).

CONCLUSION

These results demonstrate that hypertension due to excess mineralocorticoids is characterized by an increase in the gain of the baroreceptor-heart rate reflex. The reduction in baroreflex gain following adrenalectomy may delay the normalization of blood pressure.

Increased susceptibility to silicosis and TNF-alpha production in C57BL/6J mice

Toxic oxygen species and several proinflammatory cytokines are involved in the pathogenesis of silicosis. In order to understand whether factors that lead to susceptibility to ozone are also important in silicosis or not, we examined ozone-sensitive C57BL/6J mice and ozone-resistant C3H/HeJ mice as models of silicosis. We also analyzed the production of proinflammatory cytokines in both the acute and the chronic phases. On Day 2 after silica injection, the ozone-resistant C3H/HeJ mice showed significantly higher cellular responses as recognized by bronchoalveolar lavage (BAL) cell counts than did the C57BL/6J mice. In the chronic phase (Day 28 after silica injection), the ozone-sensitive C57BL/6J mice showed significantly greater responses to instilled silica judged by total protein and cell number in BAL fluid, hydroxyproline content, and histology than the ozone-resistant C3H/HeJ mice. TNF-alpha production by BAL cells after silica exposure was significantly higher in C57BL/6J mice than in C3H/HeJ mice in the chronic phase, whereas there was no significant difference in IL-1 alpha production between both strains of silica-injected mice. Also, the control C57BL/6J mice had significantly higher secretions of TNF-alpha than did the control C3H/HeJ mice in the acute phase. These results suggest that ozone-sensitive C57BL/6J mice are also more susceptible to silicosis than are ozone-resistant C3H/HeJ mice, and that the initial lower cellular responses and increase in TNF-alpha production may be related to the higher level of inflammatory and fibrotic response in the C57BL/6J mice.

Smoking promotes insidious and chronic farmer's lung disease, and deteriorates the clinical outcome

Although the prevalence of serum precipitating antibodies for farmer's lung disease (FLD) is lower in smokers than in nonsmokers and FLD predominates in nonsmokers, the affects of smoking on the clinical course of the disease is not known. We compared the clinical findings and the prognosis between 12 smokers (SM-FLD) and 31 non-smokers with FLD (NS-FLD). There was no difference in age, sex, working years on farm, clinical symptoms, laboratory findings, radiographic findings, between the two groups. However, for the type of onset on the first visit for FLD, "acute single episode" type was less common, and "recurrent" and "insidious onset" types were more common in SM-FLD than in NS-FLD (8.3 vs 58.1, 91.7 vs 41.9%, respectively, p < 0.05). Although working status and mask wearing status were not significantly different between the two groups after the diagnosis of FLD, patients with symptoms and/or radiographic abnormalities of FLD of more than 6 months were found more frequently in SM-FLD than in NS-FLD (66.7 vs 19.4%, p < 0.005). And also SM-FLD had more recurrences of FLD than NS-FLD after the initial diagnosis of FLD (1.58 +/- 1.56 vs 0.47 +/- 1.07, p < 0.05). SM-FLD tended to have lower % VC than NS-FLD (73.6 +/- 7.4 vs 88.5 +/- 3.9%, respectively, p = 0.06). Regarding the prognosis, the 10-year survival rates were 70.7% in SM-FLD, and 91.5% in NS-FLD (p < 0.05). These results suggest that smoking may make FLD insidious and chronic, and deteriorates the clinical outcome.

Effects of vasopressin V1 and V2 receptor antagonists on the development of salt-induced hypertension in Dahl rats

To determine whether the vasopressor and antidiuretic actions of arginine vasopressin (AVP) may participate in the development of salt-induced hypertension, we examined the long-term effects of AVP V1 and V2 receptor antagonists on blood pressure (BP) in Dahl-Iwai salt-sensitive (DS) and salt-resistant (DR) rats. From age 7 weeks, DS and DR rats were fed a diet containing 8% NaCl, alone (control group); 8% NaCl and 1% OPC-21268 (V1 antagonist-treated group); or 8% NaCl and 0.05% OPC-31260 (V2 antagonist-treated group). The pressor response to AVP was significantly inhibited in DS rats treated with OPC-21268. Urinary volume and water intake were significantly increased by administration of OPC-31260; this increase was greater in DR rats than in DS rats. Indirect BP measurements obtained using tailcuff plethysmography showed that DS but not DR rats developed hypertension when fed high-salt diets. However, chronic treatment with either OPC-21268 or OPC-31260 did not alter the course of hypertension in DS rats, despite the effective blocking actions of these antagonists. This finding also was confirmed by direct BP measurements. Our results indicate that even if AVP plays a role in salt-induced hypertension peripheral blockade of either subtype of AVP receptors does not prevent the development of hypertension in DS rats.

Three cases of idiopathic interstitial pneumonia with bullae seen in schoolteachers

We encountered three patients with chronic interstitial pneumonia with many bullae in the lower lung fields whose lifetime occupation was teaching school. Pathological examination of autopsy lungs of these patients revealed interstitial pneumonia and multiple bullae throughout the lungs, including the lower lobe. Since blackboard chalk has been used as a popular writing material among teachers in Japan, the mineral contents in the lungs of two of the three cases and four control cases with idiopathic interstitial pneumonia (IIP) (whose occupations were not teaching) were analyzed. The amount of deposition of total dust, inorganic dust, non-SiO2 inorganic dust, and calcium was significantly higher in the lungs of two schoolteachers compared with those of the control lungs. The amount of free silica in case 1 and alpha-quartz in case 3 were also significantly higher than in the controls. Two thirds of the chalk produced in Japan is still made from gypsum and involves small amounts of silica and other minerals, in addition to calcium. These findings indicated the deposition of chalk in the lungs of these patients with interstitial pneumonia and multiple bullae.

[A case of mycosis fungoides with pulmonary involvement: effect of etoposide and prednisolone]

Persistent coughing and bloody sputum developed in a 75-year-old man with mycosis fungoides. Chest X-ray films on admission showed combined patterns of alveolar and interstitial shadows in both lung fields. Histological examination of the transbronchial lung biopsy specimen revealed patchy infiltration of mycosis fungoides cells in alveolar septa. VEPA chemotherapy was ineffective against skin lesions and caused bacterial pneumonia, but combined treatment with etoposide (200 mg, once a week) and prednisolone (30 mg, 3 days per week) resulted in remission. The patient has been taking oral etoposide and prednisolone regularly, and has been free of skin and pulmonary lesions for two years. Combined therapy with low-dose etoposide and prednisolone may be worth trying in cases of advanced mycosis fungoides with pulmonary involvement.

[Acyclovir and guinea-pig airway smooth muscle]

Acyclovir, an anti-herpes virus drug, has been reported to affect aspirin-induced asthma (AIA). Acyclovir was reported to decrease the sensitivity to aspirin in some AIA patients. Although the hypothesis that AIA is related to viral infection has been stated, there is no proof that patients with AIA are infected with a specific virus. Therefore, whether the effect of acyclovir on AIA is due to an antiviral effect is not clear. We hypothesized that acyclovir directly affects airway smooth muscle. To test this hypothesis, we examined whether acyclovir can directly contract or relax guinea-pig airway strips, and whether it can modify contraction or relaxation induced with several agents in vitro. Acyclovir did not directly affect basal smooth muscle tone and did not affect the responses to leukotriene D4, prostaglandin E2, carbachol, or KCl. We conclude that acyclovir has no direct effect on the function of guinea-pig airway smooth muscle.

[A patient with cryptogenic organizing pneumonitis who presented with multiple patchy shadows]

A 62-year-old woman was admitted to our institution for abnormal shadows on a screening chest roentgenogram. An immunoelectrophoresis test on admission revealed a polyclonal gammopathy. In her bronchoalveolar lavage fluid, the percentage of lymphocytes was found to be high: 47%. These results indicated an abnormal immunological state. A chest X-ray film showed multiple patchy shadows in both lungs. A chest CT scan revealed that the shadows were distributed peripherally, and abutted the pleura. Before treatment, the lesions enlarged toward the hilum concentrically, and cleared from the pleural side. This change is characteristic of cryptogenic organizing pneumonitis. The pathological finding at open lung biopsy was organizing pneumonitis. Bronchiolitis obliterans was not pathologically recognized. The shadows on the chest X-ray film almost completely disappeared after treatment with predonisolone at a daily dose of 30 mg. We diagnosed this as a case of cryptogenic organizing pneumonitis with typical shadows.

[Role of viral infections in acute exacerbation of idiopathic interstitial pneumonia]

To evaluate the possibility that viral infections can trigger acute exacerbations of idiopathic interstitial pneumonia (IIP), we analyzed data from 105 patients with IIP. Acute exacerbation was defined as an increase in dyspnea, a decrease in PaO2 by more than 10 Torr, and worsening of chest radiographic findings within one month. Viral infection was said to be involved when patients had more than a 4-fold change in viral antibody titer or viral inclusion bodies in sputum during the acute exacerbation. Of the 105 patients with IIP, 30 had acute exacerbations. Among these 30 patients, viral infection was said to be involved in 11 (37%). Presumptive viruses were influenza virus (n = 6), parainfluenza virus (n = 1), herpes simplex virus (n = 1), RS virus (n = 1), and cytomegalovirus (n = 2). The levels of serum immunoglobulin A (IgA) before acute exacerbations were significantly lower (p < 0.05) in patients in whom viral infection was said to be involved. These results suggest that viral infection associated with a low value of serum IgA is an important trigger of acute exacerbations of IIP.

[Factors influencing patterns of airway response after allergen challenge in patients with bronchial asthma]

We examined patterns of airway response of thirty nine asthma patients who had positive responses on allergen inhalation tests. Six types of inhaled allergens were used: house dust mite, animal, pollen, plant, mold, and others. Three patterns of responses were found: isolated immediate asthmatic response (IAR), immediate and late response (Dual), and isolated late asthmatic response (LAR). No relationship was found between the pattern of response and pulmonary function, airway sensitivity, IgE RIST titers, numbers of eosinophils, or concentration of inhaled antigens. Animal antigens tended to cause a dual response, and molds did only rarely. Ten of 39 challenged patients had an isolated LAR, half of which were caused by mold antigen inhalation. RAST scores were lower in isolated LAR than in other responses. Changes in the number and proportion of peripheral leukocytes during the challenge tests were also studied. Total leukocyte count had increased significantly in the isolated LAR group by 24 hours after the inhalation. These results suggest that the pattern of airway response after inhalation depended in part on the type of inhaled antigen, and that non-IgE mediated immune reactions have some role in the isolated LAR.

Dairy farmers have increased methacholine bronchial responsiveness independent of sensitization to mold antigens

Patients with farmer's lung disease (FLD) and dairy farmers have nonspecific bronchial hyperresponsiveness. To examine the factors determining bronchial hyperresponsiveness among dairy farmers, we studied airway functions, airway responses to inhaled methacholine, serum total IgE levels, and antigen-specific IgE levels in 37 dairy farmers and 11 local control subjects. The 37 dairy farmers consisted of three groups; 12 farmers with episodes of FLD (FLD group), 13 farmers with serum antibody to Micropolyspora faeni (MF) and/or Thermoactinomyces vulgaris (TV) but without episodes of FLD (Ab(+) group), and 12 farmers without serum antibodies to MF and TV and without episodes of FLD (Ab(-) group). Pulmonary function tests showed small airways disorders among farmers (each of the three groups versus control subjects; p < 0.05). Methacholine provocation test, utilizing PD35Grs (a cumulative dose of methacholine that induces 35% reduction in respiratory conductance [Grs]), showed bronchial hyperresponsiveness in each group of dairy farmers compared with that in control subjects (Log PD35Grs, mean +/- SEM: 1.22 +/- 0.18, 1.00 +/- 0.17, and 1.20 +/- 0.20, respectively, versus 2.10 +/- 0.09; p < 0.001). However, there was no statistically significant difference in bronchial responsiveness among the three groups of dairy farmers. In addition, there was no significant difference in serum total IgE levels and specific IgE antibodies among the four groups. These results suggest that the bronchial hyperresponsiveness to methacholine among dairy farmers is not due to past episodes of FLD or sensitization to MF and/or TV, but is possibly due to the occupational environment of dairy farming.

Normal sympathetic vasomotor and cardiac parasympathetic activities in patients with primary aldosteronism: assessment by spectral analysis

The role of the autonomic nervous system in hypertension due to mineralocorticoid excess remains unclear. To address this issue, we performed power spectral analysis of blood pressure (BP) and RR interval oscillations in 20 patients with primary aldosteronism (PA), 54 patients with essential hypertension (EH) and 45 normotensive (NT) subjects. Blood pressure and the degree of organ damage were similar between PA and EH groups. Age did not differ between the three groups. The Mayer wave power spectrum (MWP) of BP (approx. 0.1 Hz), an index of sympathetic vasomotor tone, was smaller in patients with PA than in patients with EH either while subjects were supine (systolic/diastolic; 3.9 +/- 3.2 (SD)/1.5 +/- 1.3 vs. 5.5 +/- 4.2/2.1 +/- 1.6 mmHg2, P < 0.05 for both) or standing (7.6 +/- 6.6/3.0 +/- 3.0 vs. 17.7 +/- 23.7/7.2 +/- 8.3 mmHg2, P < 0.05 for both). Supine respiratory-related power spectrum (RRP) of the RR interval (approx. 0.25 Hz), an index of cardiac parasympathetic tone, was greater in patients with PA than in patients with EH (545 +/- 574 vs. 302 +/- 464 ms2, P < 0.01). The MWP of BP and the RRP of the RR interval were similar between patients with PA and NT subjects. Adrenalectomy reduced the 24-h mean BP (-18 mmHg for systolic BP, P < 0.001; -12 mmHg for diastolic BP, P < 0.01) and increased the 24-h mean heart rate (+8 bpm, P < 0.001). Furthermore, the diastolic MWP increased mildly (+32%, P < 0.05) and the RRP of the RR interval decreased dramatically (-75%, P < 0.01) following adrenalectomy. These results suggest that both vascular sympathetic and cardiac parasympathetic regulatory systems have minor roles in the maintenance of hypertension in patients with PA. The autonomic nervous system contributes more to the maintenance of BP following than prior to adrenalectomy. This information may be useful for the management of hypertension still persists after removal of adrenal adenoma.

Pressor effect of recombinant human erythropoietin: results of ambulatory blood pressure monitoring and home blood pressure measurements

We investigated whether treatment of anemic hemodialysis patients with a low dose of recombinant human erythropoietin (erythropoietin) for a short period would increase their blood pressure. Ambulatory blood pressure monitoring and home blood pressure measurements were used to detect minute increase in blood pressure. Thirty-two patients with a hematocrit of 25% or less received erythropoietin at the dose of 4500 IU/week, by the intravenous route for 8 weeks. Erythropoietin increased the hematocrit from 20.9 +/- 2.1 to 26.2 +/- 2.1%. Erythropoietin elevated mean ambulatory blood pressure by 5 mmHg or more in two-thirds of patients (n = 20; pressor group), while it elevated home mean blood pressure by 5 mmHg or more in one-third of patients (n = 11). An increase in clinic mean blood pressure by more than 5 mmHg was observed only in one-fourth of patients (n = 7). Circadian variation of blood pressure (nocturnal fall and diurnal rise) had been attenuated in the patients of the pressor group before erythropoietin treatment and erythropoietin decreased the nocturnal fall of blood pressure further more. Erythropoietin elevated nocturnal blood pressure more than diurnal blood pressure. Therefore, the increase in blood pressure induced by erythropoietin was detected more reliably by ambulatory blood pressure monitoring. There was no relation between the change in hemoglobin concentration and the increase in ambulatory blood pressure induced by erythropoietin. Erythropoietin tended to decrease cardiac output and plasma volume while it increased total peripheral resistance. It also decreased plasma norepinephrine and vasopressin levels but did not affect other humoral factors. Although the pressor effect of erythropoietin treatment for 8 weeks at the dose of 4500 IU/week was not evident on clinic blood pressure measurements, any increase in blood pressure determined by ambulatory blood pressure should be treated carefully to reduce the risk of a cardiovascular complication in patients receiving hemodialysis.

Beta 2 adrenergic receptor gene restriction fragment length polymorphism and bronchial asthma

BACKGROUND

Beta 2 adrenergic dysfunction may be one of the underlying mechanisms responsible for atopy and bronchial asthma. The gene encoding the human beta 2 adrenergic receptor (beta 2ADR) has recently been isolated and sequenced. In addition, a two allele polymorphism of this receptor gene has been identified in white people. A study was carried out to determine whether this polymorphism is functionally important and has any relation to airways responsiveness, atopy, or asthma.

METHODS

The subjects studied were 58 family members of four patients with atopic asthma. Restriction fragment length polymorphism (RFLP) with Ban-I digestion of the beta 2ADR gene was detected by a specific DNA probe with Southern blot analysis. Airways responses to inhaled methacholine and the beta 2 agonist salbutamol, the skin prick test, and serum IgE levels were also examined and correlated to the beta 2ADR gene RFLP. In addition, measurements of cAMP responses to isoproterenol in peripheral mononuclear cells were performed in 22 healthy subjects whose genotype for beta 2ADR was known.

RESULTS

A two allele polymorphism (2.3 kb and 2.1 kb) of the beta 2ADR gene was detected in the Japanese population. Family members without allele 2.3 kb (homozygote of allele 2.1 kb) had lower airways responses to inhaled salbutamol than those with allele 2.3 kb. The incidence of asthma was higher in those without allele 2.3 kb than in those with allele 2.3 kb. The beta 2ADR gene RFLP had no relation to airways responses to methacholine and atopic status. cAMP responses in peripheral mononuclear cells of the subjects without allele 2.3 kb tended to be lower than those of the subjects with allele 2.3 kb.

CONCLUSIONS

These results suggest that Ban-I RFLP of the beta 2ADR gene may have some association with the airways responses to beta 2 agonists and the incidence of bronchial asthma.

The effect of graded calcium infusions on rhythmic blood pressure oscillations in normal man

This study was designed to determine whether calcium contributes to the regulation of rhythmic oscillations in blood pressure. Six normal subjects received sequential 1-h infusions of calcium gluconate (1.5, 3.0 and 4.5 mg calcium/kg/h) during continuous blood pressure (Finapres) monitoring. The plasma ionized calcium ([Ca2+]) concentration increased from 4.6 +/- 0.07 mg/dl to 5.97 +/- 0.20 mg/dl (p < 0.01) with infusion. The mid-frequency (0.07-0.14 Hz, Mayer wave) power spectrum of diastolic blood pressure was depressed slightly following the first dose but increased significantly following the final dose (p < 0.05). The high-frequency (0.15-0.40 Hz) power spectrum of systolic blood pressure decreased following the first dose (p < 0.05) and subsequently remained low. The low-frequency (0.02-0.6 Hz) power spectrum was not affected. These results demonstrate that graded hypercalcaemia affects blood pressure oscillations in man. Our data suggest that the amplitude of the Mayer wave, a clinical marker of sympathetic vascular tone, is modulated in part by calcium.

[Autologous blood transfusion in cardiac surgery over 70-year-old patients]

We discussed the problems for autologous blood transfusion particularly in the preoperative blood donation about the patients over 70-year-old who underwent cardiac surgery in contrast with the younger patients. Following results were obtained: 1) Because aged patients have the tendency of anemia before predonation, full storage of blood donation could not be successed. 2 of 8 over 70-year-old patients were able to do the preoperative phlebotomy, and their mean volume were 355 gram as whole blood. On the other hand, 96% patients in younger group were phlebotomized preoperatively, and their mean value of storaged blood volume were 757 gram. 2) As the examinations about the iron-related parameters, not all aged patients were iron deficiency status. Their reticulocyte counts were nearly equal level to the younger group and plasma concentration of erythropoietin were higher in the aged patients than that in the younger group. These results indicate that erythropoiesis in the bone marrow was deteriorated in the aged patients. 3) In aged patients, all of them were required homologous blood transfusion at their perioperative terms. We thought that they have had the anemia before preoperation and our tolerable, allowable level to the postoperative anemia was not lower in the aged patients as against to the younger group. 4) We performed the autologous plasma donation with the membranous plasma separator added to the whole blood donation. It was easy and safe method, and circulatory indices were not changed before and after plasma-separation even in the aged patients. These autologous plasma were usefully administered as the volume expander postoperatively.