Amyloid beta-protein precursor accumulates in dystrophic neurites of senile plaques in Alzheimer-type dementia

We raised two rabbit antisera against synthetic peptides corresponding to the carboxyl- and amino-terminal regions of the predicted amyloid beta-protein precursor (APP). Both antisera recognized the same 106-135 kDa proteins of human brain extract by immunoblot analysis. Immunocytochemical studies showed that these antisera both reacted with the same dystrophic neurites within the senile plaques of Alzheimer brains. These results indicated that APP accumulated in the dystrophic neurites of the senile plaques.

Effect of methylergometrine maleate (methergin) on electrical and mechanical activities of pregnant human myometrium

The effect of methylergometrine maleate (methergin) on electrical and mechanical activities of pregnant human isthmic myometrium was examined. Methergin (10(-8)-10(-6) g/ml) enhanced plateau potential and contraction, however, the effects were not prominent. Plateau potential and contraction were also potentiated after pretreatment with 10(-7) g/ml phentolamine (alpha-blocker), however 10(-7) g/ml methergin further increased these effects. It is suggested that methergin might potentiate contractions by changing the pattern of action potentials and not by alpha-adrenoceptor.

[The obstetric prognosis and neonatal outcome of pregnant women with psychiatric disorders]

Obstetric prognosis and neonatal outcome of pregnant women with psychiatric disorders were retrospectively investigated. 1. Out of 1.472 deliveries at Saga Medical School from April 1983 to July 1988, there were fourteen cases (0.95%) involving psychiatric disorders-six of epilepsy, one of anxiety neurosis and seven of schizophrenias. 2. Total blood loss was relatively great in four epileptic patients. However, the general prognosis for each was good and the neonatal outcome was uneventful. 3. As for schizophrenic patients, six out of seven cases grew worse during the pregnancy and four in the postpartum period. Three cases underwent cesarean section due to their mental illness. 4. We made inquiries about the postpartum life of schizophrenic mothers and children, and received five answers (70.1%). It was found that schizophrenic mothers could not bring up the baby by themselves; they needed the help of their husbands and their own mothers. It is concluded that consistent management by both psychiatrist and obstetrician from the antepartum period to postpartum life are required for psychotic mothers and their children to obtain a favorable prognosis, and a follow-up system is desirable for the physical as well as the mental growth of the infants.

The complement system in the acute phase of myocardial infarction

Although some studies suggest that complement activation is involved in the development of acute myocardial infarction, there has been little convincing evidence of a change in the complement system in patients suffering from myocardial infarction. In this study circulating levels of C3a, C3, C4 and the total hemolytic complement titer (CH50) were serially measured in 12 patients with acute myocardial infarction up to 10 days after an attack. The plasma C3a level was greatly elevated throughout the post-attack observation period. The C3, C4 and CH50 levels were significantly increased above those controls on days 8, 9 and 10 after infarction. These findings indicate that there is complement activation in patients with acute myocardial infarction, and suggest a pathogenetic role for complement activation in the development of myocardial damage after infarction.

Effects of external calcium, magnesium, and temperature on spontaneous contractions of pregnant human myometrium

Spontaneous isometric contractions of small isolated segments from the isthmic region of pregnant human myometrium were recorded to clarify the characteristics of and influences of experimental conditions on contractions. There is a spontaneous periodicity in membrane activity of human myometrium, and contractions evoked with a sustained electric stimulus were affected by spontaneous rhythmic contractions. The frequency of contractions increased markedly, but their duration decreased when temperature of the bathing fluid was increased from 26 degrees C to 39 degrees C. Both excess (7 mM) and low (0.5 mM) calcium levels suppressed the generation of spontaneous contraction. Frequency and half-duration gradually decreased when external magnesium was increased from 0 mM to 3.6 mM. These results indicate that the pattern of contraction depends on the frequency of and intervals between each action potential, and that spontaneous contractility-particularly its frequency-is extremely sensitive to external temperature and ionic conditions.

Changes in serum calcium, magnesium, cyclic AMP and monoamine oxidase levels during pregnancy and under prolonged ritodrine treatment for preterm labor

Changes in serum levels of calcium, magnesium, cAMP and monoamine oxidase (MAO) activity throughout pregnancy and during prolonged treatment for preterm labor with ritodrine were studied. cAMP levels in the third trimester of pregnancy were found to be significantly high and postpartum MAO activity was significantly low. In cases of preterm labor, serum levels of calcium, magnesium and MAO activity were significantly low during the initial stage of ritodrine administration, then recovered after more than 1 week of treatment despite the fact that given doses and serum levels of ritodrine remained constant and that the serum level of cAMP was still high. These results suggested that a control mechanism for MAO activity during pregnancy might exist due to an increase in catecholamine and that the beta 2-effect of ritodrine induced a lowering in serum calcium and magnesium levels. However, some homeostatic mechanism to regulate the ions might come into play later on the mechanism of down-regulation of ritodrine.

Clinical features of small contraction wave recorded by an external tocodynamometer

Clinical features of the small contraction wave recorded by a guardring tocodynamometer were examined retrospectively. This study included 578 patients and 6363 cardiotocographs ranging from 20 to 42 weeks of gestation. The small wave was observed in 7.5% of the cardiotocographs examined, and the rate of small-wave appearance in each gestational week tended to decrease gradually as the pregnancy progressed. This was not observed after 41 weeks of gestation. The small wave-positive group had relatively poor obstetric parameters and fetal outcome, and the small wave was frequently observed in cases of effective beta 2-stimulant intravenous infusion for the treatment of preterm labor. These results suggest that the small wave represents some degree of contractility and is ominous in general; however, the appearance of the wave does not lead to a poor prognosis in preterm labor if large phasic contractions can be abolished by beta 2-stimulant treatment.

Anaphylactoid reaction to oxytocin during cesarean section

A case of an allergic reaction to synthetic oxytocin administered during cesarean section is reported. Epinephrine was more effective in improving the severe hypotension than ephedrine. The incidence of anaphylactoid reaction to oxytocin is very low, but this potential problem must always be kept in mind in daily obstetric practice.

Characteristics of action potentials and contractions evoked by electrical-field stimulation of pregnant human myometrium

Evoked electrical and mechanical activities of pregnant human myometrium were recorded by the single sucrose-gap method. Each muscle strip has an individual rhythm of membrane excitability and the evoked activity was affected by spontaneous membrane fluctuation. However, high-frequency stimulation caused changes in the rhythm of fluctuation and the pattern of action potential converted from plateau to spike type. Twitch contractions evoked by spike potentials were summated and became fused tetanus in accordance with shortening of the pulse interval. This method is suitable for clarifying the excitation-contraction relationship in human myometrium.

Central alpha 2-adrenergic stimulation increases neurointermediate lobe immunoreactive beta-endorphin in spontaneously hypertensive rats

A possible influence of the central alpha 2-adrenergic system on beta-endorphin was examined in rat anterior pituitary, neurointermediate lobe, and plasma. The concentration of beta-endorphin in anterior pituitary, neurointermediate lobe, and plasma was determined by radioimmunoassay 15 minutes after subcutaneous injection of clonidine in 14-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). Clonidine reduced the concentration of the plasma beta-endorphinlike immunoreactivity in SHR and to a lesser extent in WKY. No significant changes in the concentration of beta-endorphinlike immunoreactivity were observed in anterior pituitary. Clonidine increased the concentration of neurointermediate lobe beta-endorphinlike immunoreactivity in SHR in a dose-related manner but did not affect the concentration in WKY. Administration of yohimbine (1 mg/kg) completely blocked the clonidine-induced increase of neurointermediate lobe beta-endorphinlike immunoreactivity in SHR, while prazosin (1 mg/kg) had no effect. These data suggest that the central alpha 2-adrenergic activation increases the neurointermediate lobe concentration of beta-endorphinlike immunoreactivity in SHR by suppressing beta-endorphin release from the neurointermediate lobe into the circulation.

Erythrocyte water content in spontaneously hypertensive rats and DOCA-salt hypertensive rats

Intra-erythrocyte water, sodium and potassium contents were measured in spontaneously hypertensive rats (SHR) and deoxycorticosterone acetate (DOCA)-salt rats. In 12 week old SHR, the intra-erythrocyte water content was slightly but significantly lower than that in age-matched Wistar-Kyoto (WKY) rats. SHR also exhibited a significantly lower intra-erythrocyte potassium content, but sodium content tended to be elevated. Although sodium content was not correlated with the water content, potassium content was. In DOCA-salt hypertensive rats, the intra-erythrocyte sodium content was higher than that in age-matched normotensive Sprague-Dawley rats by about 33%, but the water and potassium contents were similar. There were no significant correlations between these parameters. These findings provide no evidence of water retention in erythrocytes from DOCA-salt rat or SHR even though intra-erythrocyte sodium content was increased.

Effect of oxytocin on spontaneous electrical and mechanical activities in pregnant human myometrium

Spontaneous intracellular electrical activity and contraction of pregnant human myometrium were recorded by the single sucrose-gap method, and the effects of oxytocin on the muscle were studied. In pregnant human myometrium at term, both plateau and spike types of action potentials were observed. All contractions were well synchronized with each action potential. Oxytocin, 10(-2) U/ml, potentiated spontaneous contractions by enhancing the plateau part of action potentials; spike-type configuration became plateau. When extracellular ionized calcium was removed, spontaneous activities disappeared, while 10(-2) U/ml of oxytocin could evoke action potentials and contractions but these were smaller than those of the controls. Spontaneous activities also disappeared when ionized calcium was increased to 5 mmol/L, but oxytocin evoked plateau potentials and contractions remarkably. Diltiazem (ionized calcium antagonist), 10(-6) gm/ml, suppressed the spontaneous activity, but oxytocin evoked action potentials and contractions in high frequency, the duration of the action potential being short and the contraction being small. In the presence of 10(-4) gm/ml of diltiazem, 10(-2) U/ml of oxytocin could not evoke any action potentials but did evoke small and long contractures, while in a high ionized potassium contracture experiment, oxytocin potentiated the tonic phase. These results suggest that oxytocin can increase spontaneous contractions by enhancing plateau potentials and that this effect requires sufficient extracellular ionized calcium. In this potentiation, the effects on frequency and amplitude of contractions might vary. It is also suggested that oxytocin may evoke a contracture in the absence of an action potential by releasing calcium from intracellular storage sites.

Cytoplasmic free [Ca2+] is not increased in the platelets of deoxycorticosterone-salt and spontaneously hypertensive rats

The cytoplasmic free calcium concentration ([Ca2+]i) in the platelets of spontaneously hypertensive rats (SHR), Wistar-Kyoto rats (WKY), deoxycorticosterone-salt hypertensive rats (DOC) and normotensive Sprague-Dawley rats (SD) was measured with the fluorescent dye, quin-2-tetra-acetoxymethyl ester. No significant difference in platelet [Ca2+]i was found between SHR and WKY or between DOC and SD rats. No correlations were found between systolic blood pressure and [Ca2+]i. These results suggest that the elevation of platelet [Ca2+]i does not necessarily accompany hypertension in rats.

Decreased water and potassium content in erythrocytes in essential hypertension

The water content in erythrocytes of subjects with borderline or established essential hypertension was measured by using gas-liquid chromatography and was found to be lower than that in normotensive controls (p less than 0.01). The water content in erythrocytes of normal controls (n = 14), borderline hypertensive subjects (n = 18), and established essential hypertensive subjects (n = 23) was (mean +/- SE) 71.0 +/- 0.2%, 69.9 +/- 0.2%, and 69.3 +/- 0.1% (vol/vol), respectively. A definite negative correlation was found between water content of erythrocytes and mean arterial pressure in normotensive and hypertensive subjects (n = 60, r = -0.59, p less than 0.001). Although there was no statistically significant between-group difference in the sodium content, the potassium content of erythrocytes from subjects with essential hypertension was significantly lower than that of normotensive controls (0.205 +/- 0.003 vs 0.222 +/- 0.004 mumol/mg dry red blood cells; p less than 0.01). There was no between-group correlation of sodium and water content in erythrocytes, but the potassium content correlated with the water content (n = 46, r = 0.49, p less than 0.001).

[Left ventricular wall motion abnormalities evaluated by factor analysis as compared with Fourier analysis]

Factor analysis was applied to multigated cardiac pool scintigraphy to evaluate its ability to detect left ventricular wall motion abnormalities in 35 patients with old myocardial infarction (MI), and in 12 control cases with normal left ventriculography. All cases were also evaluated by conventional Fourier analysis. In most cases with normal left ventriculography, the ventricular and atrial factors were extracted by factor analysis. In cases with MI, the third factor was obtained in the left ventricle corresponding to wall motion abnormality. Each case was scored according to the coincidence of findings of ventriculography and those of factor analysis or Fourier analysis. Scores were recorded for three items; the existence, location, and degree of asynergy. In cases of MI, the detection rate of asynergy was 94% by factor analysis, 83% by Fourier analysis, and the agreement in respect to location was 71% and 66%, respectively. Factor analysis had higher scores than Fourier analysis, but this was not significant. The interobserver error of factor analysis was less than that of Fourier analysis. Factor analysis can display locations and dynamic motion curves of asynergy, and it is regarded as a useful method for detecting and evaluating left ventricular wall motion abnormalities.

Central alpha-activation by clonidine reduces plasma level of beta-endorphin in patients with essential hypertension

Whether peripheral beta-endorphin contributes to the antihypertensive action of clonidine was examined by measuring plasma levels of beta-endorphin-like immunoreactivity (beta EpLI) after acute administration of clonidine in patients with essential hypertension. Administration of clonidine (0.225 mg) in one dose significantly lowered blood pressure, decreased heart rate and reduced the plasma level of beta EpLI and ACTH, while the placebo had no effect on blood pressure, heart rate or plasma level of beta EpLI suggesting that peripheral beta-endorphin does not play a major role in the antihypertensive action of acute clonidine administration.

[Left ventricular function in essential hypertension during isoproterenol infusion]

The left ventricular function of 23 patients with essential hypertension was investigated during infusion of isoproterenol (ISP). These patients consisted of 13 without cardiac hypertrophy (Group NH) and 10 with cardiac hypertrophy (Group HH). Ten normotensive subjects served as normal controls. To assess left ventricular functions, M-mode echocardiograms were recorded at rest and after ISP infusion for 5 minutes (0.005 and 0.01 microgram/kg/min). There were no significant differences in peak negative dD/dt in all groups at rest. But peak negative dD/dt of Group HH significantly decreased after an infusion of 0.005 microgram/kg/min ISP (Group N: 3.43 +/- 0.69, Group NH: 3.15 +/- 0.61, and Group HH: 2.49 +/- 0.48 cm/sec, respectively). The peak negative dD/dt of Group HH was also significantly decreased after a dose of 0.01 microgram/kg/min. Among all patients with hypertension, peak negative dD/dt correlated inversely with left ventricular mass (LVM) after the infusion of ISP (0.005 microgram/kg/min: r = -0.64, p less than 0.001, 0.01 microgram/kg/min: r = -0.68, p less than 0.001). The peak positive dD/dt of Group HH was significantly decreased only when compared with that of Group N at rest (Group N: 3.15 +/- 0.75, Group NH: 3.02 +/- 0.86, and Group HH: 1.92 +/- 0.68 cm/sec, respectively). The difference between the peak positive dD/dt of Group HH and that of Group N was more prominent after the infusion of ISP than at rest. Among all patients with hypertension, the peak positive dD/dt was inversely related to LVM at rest (r = -0.64, p less than 0.002). There was a similar relation between the two indexes after the infusion of ISP. Peak positive dD/dt was related to peak negative dD/dt after a dose of 0.01 microgram/kg/min in Group HH (r = 0.67, p less than 0.05). There was no significant difference in heart rate, change in blood pressure, or total peripheral vascular resistance after the infusion of ISP. It is concluded that diastolic left ventricular dysfunction and latent systolic left ventricular dysfunction are related to increased LVM in Group HH. It seems that after the infusion of ISP severe diastolic left ventricular dysfunction is related to latent systolic left ventricular dysfunction.

Pseudo-coarctation of the abdominal aorta associated with renovascular hypertension

A case of pseudo-coarctation of the abdominal aorta associated with renovascular hypertension has been reported. The abdominal aorta of the patient was kinked at the level of L1-L2 without a pressure gradient, which was consistent with pseudo-coarctation of aorta. Both renal arteries arose from the aorta at the level of lower T12 and had severe multiple stenoses. We have discussed the possible etiology of the developmental abnormalities of the arterial system in this patient.

Significance of the measurement of urinary alanine aminopeptidase and N-acetyl-beta-D-glucosaminidase activity in evaluating patients with essential hypertension

To examine the relationship between the urinary levels of alanine aminopeptidase (AAP) or N-acetyl-beta-D-glucosaminidase (NAG) and the advance of essential hypertension, we measured the urinary levels of these enzymes in 20 normotensive controls, 8 subjects with borderline hypertension and 40 subjects with WHO stage I and stage II essential hypertension. The urinary level of NAG in stage II hypertensives was higher than that in the normotensives, and borderline or stage I hypertensives (p less than 0.01). Systolic blood pressure and the urinary level of NAG was positively correlated in hypertensives (rs = 0.43, p less than 0.01). The urinary level of NAG was correlated inversely with renal blood flow (rs = -0.61, p less than 0.01). The urinary level of AAP in stage II hypertensives was also higher than that in the normotensives (p less than 0.01) or stage I hypertension (p less than 0.01), but the urinary AAP level was not significantly correlated with systolic blood pressure or renal blood flow in hypertension.

[The pattern of spontaneous contraction and the effects of Mg++ and terbutaline on pregnant human myometrium]

The isometric spontaneous contraction and K-contracture of pregnant human myometrium were recorded in order to study the effects of external Mg++ and the correlation between Mg++ and terbutaline. Electrical activities were also recorded with a single sucrose-gap method. Maximum tension, frequency and half duration of spontaneous contractions were not significantly different among all specimens. Maximum tension of the spontaneous contraction was lower than the longitudinal muscle of pregnant rat and higher than the circular one. The frequency was lower and the duration was longer than rat myometrium. Mg++ exhibited the inhibition of the spontaneous contraction and decreased the gradient of pacemaker potential and duration of action potentials. Phasic contraction of K-contracture was also inhibited by the pre-incubation with Mg++. Mg++ rich medium shifted the dose-response curve of terbutaline to the left and the pre-incubation with Mg++ increased the inhibitory effect of terbutaline on the tonic part of K-contracture. The results indicated that human myometrium might be constructed of plural muscle bundles with different characteristics, and Mg++ inhibited the spontaneous contraction by affecting the membrane activities and enhanced the terbutaline effect by penetrating into the membrane.

[Significance of the fourth heart sound in patients with angina pectoris]

To determine the physiological significance of the fourth heart sound at rest in patients with angina pectoris without previous myocardial infarction, the tension time index (TTI) and the ratio of the diastolic pressure time index (DPTI) to (DPTI/TTI) were calculated from the recordings of the left ventricular and aortic pressure curves. Thirty patients were subjected to the study and they were classified into two groups: Group A consisted of 15 patients with the fourth heart sound and Group B of 15 patients without it. Nine cases of atypical chest pain without the fourth heart sound served as control group. TTI was significantly higher in Group A than in Group B (p less than 0.01) and control group (p less than 0.01) (2,552 +/- 489 mmHg X sec/min in Group A, 2,024 +/- 425 mmHg X sec/min in Group B, and 2,023 +/- 209 mmHg X sec/min in control group). DPTI/TTI was significantly lower in Group A than in Group B (p less than 0.01) and control group p less than 0.001) (1.16 +/- 0.19 in Group A, 1.55 +/- 0.39 in Group B, and 1.45 +/- 0.15 in control group). Left ventricular systolic pressure tended to be higher in Group A than in Group B and control group. There was no significant difference in left ventricular end-diastolic pressure, left ventricular ejection fraction and cardiac index among three groups and there was no difference in the prevalence of left ventricular asynergy on left ventriculography between Group A and Group B.(ABSTRACT TRUNCATED AT 250 WORDS)

[The pattern of spontaneous contraction and the effects of catecholamines on pregnant human isthmic myometrium]

The spontaneous isometric contraction of human isthmic myometrium was recorded with regard to the stage of pregnancy, the run of muscle bundles and the resected part of the muscles. Then, the effects of noradrenaline or terbutaline and the relationship between beta-inhibition and Mg2+ were also studied. 1. The frequency of spontaneous contraction was lower than that of rat myometrium, and the amplitude was smaller than the longitudinal muscle of rat under the same conditions. 2. The pattern of the spontaneous contractions was almost the same in different muscle bundles resected from the serosal or endometrial side, and also at different stages of pregnancy. 3. The effect of noradrenaline (10(-12)-10(-6) g/ml) always exhibited alpha-excitatory action and terbutaline (10(-8)-10(-6) g/ml) induced beta-inhibition in every strip. These actions depended on the concentration of the drug. 4. The frequency of spontaneous contractions was gradually decreased and the beta-inhibition of terbutaline (10(-7) g/ml) was progressively potentiated with the increase in external Mg concentration. These results show the fundamental difference in the pattern of spontaneous contractions due to the difference in the arrangement of muscle bundles or species between human and rat, and also suggest that the human myometrium possesses both alpha- and beta-receptors of catecholamine, and the combined therapy using MgSO4 and beta 2-stimulants for premature labor is available, although the physiological role of adrenergic innervation is still unknown.

[Factors influencing the pattern-change of spontaneous activity in the pregnant rat myometrium]

Near the end of pregnancy, both the longitudinal and circular muscles of the rat uterus exhibit characteristic changes, and especially in circular muscle, the plateau-type action potential observed in mid-pregnancy changes into the burst discharge which is apparently prerequisite for normal delivery. This study concerned the effects of the ovarian hormones, the stretch of the uterine wall, and the fetoplacental unit on the longitudinal muscle of the pregnant rats, and the results were compared with the activity of the circular muscle in discussion. 1. Spontaneous electrical and mechanical activities of the longitudinal muscle of the unilaterally pregnant rats showed the marked difference between the gravid and nongravid uterine horns. 2. Normal and dislocated horns of unilaterally placental-dislocated rats showed the same spontaneous activities in the longitudinal muscles. 3. In ovariectomized rats, estrogen-treated group delivered normally and the spontaneous activities of the longitudinal muscle showed normal pattern. On the contrary, estrogen-untreated group delivered abnormally, however the spontaneous activities of the longitudinal muscle were normal. The results showed that the important factor for the characteristic change of the longitudinal muscle during pregnancy is the stretch of the uterine wall, and that the roles of longitudinal and circular muscles for the parturition may be different.