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Biomedical subjects

T Funabashi

Publications and source records attributed to T Funabashi.

At least 37 records · Page 2Linked to original sources
PubMed1991

Intraventricular injection of vasoactive intestinal polypeptide facilitates the development of amygdaloid kindling.

To determine the involvement of vasoactive intestinal polypeptide (VIP) in the development of kindling in rats, VIP or antibody to VIP (anti-VIP) was injected into the third ventricle after the daily stimulation of the basolateral amygdala. The number of stimulations required to reach full amygdaloid kindling was significantly smaller in rats treated with VIP than rats treated with saline, whereas it increased significantly in rats treated with anti-VIP compared to that in the rats treated with either saline or normal rabbit serum. The results suggest that VIP participates in the development of amygdaloid kindling as a facilitatory factor.

Amygdala↗
PubMed1991

Naloxone increases the frequency of the electrical activity of luteinizing hormone-releasing hormone pulse generator in long-term ovariectomized rats.

Characteristic increases in neuronal activity accompanied by the initiation of each luteinizing hormone (LH) pulse have been successfully recorded in freely moving ovariectomized rats by means of multiunit activity (MUA) recording techniques. In the present study, the effect of the opioid receptor antagonist naloxone on this neuronal activity was examined in rats ovariectomized for 6-10 weeks. Electrodes were chronically implanted into the medial basal hypothalamus (n = 78) or the medial preoptic area (n = 29). During the MUA recording, blood samples were taken through an indwelling atrial cannula at 3- or 6-min intervals to determine the serum LH concentration. Naloxone was administered intravenously for 1 h by either intermittent injection every 6 min (0.05 mg/kg, 10 times) or continuous infusion (0.1, 0.2 and 0.5 mg/kg/h). Explosive rises in the MUA (volleys) associated with the initiation of LH pulse were recorded in 7 animals in which the tips of electrodes were located in the arcuate nucleus-median eminence region. In 5 animals studied, the mean (+/- SE) duration and interval of the MUA volleys were 2.1 +/- 0.1 and 22.1 +/- 0.9 min, respectively. Naloxone given every 6 min significantly increased the duration to 2.6 +/- 0.1 min, and decreased the interval to 9.5 +/- 0.9 min. This naloxone treatment disturbed the clear pulsatility of LH secretion observed in the pretreatment control period. Analysis of the effects of naloxone infused at 3 different doses revealed that the facilitatory effects of naloxone on the duration and frequency of the MUA volleys were dose-dependent.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Naloxone injected into the preoptic region has hypophysiotropic and seizurogenic actions in rats.

The effects of microinjection of naloxone, an opiate receptor antagonist, into the medial preoptic area (MPO) and diagonal band of Broca (DBB) on luteinizing hormone (LH) and prolactin (PRL) secretion were examined in the intact male rat and female rat in diestrus 1. In both the male and female rats, the injection of 50 micrograms naloxone at 1300 h produced an acute, two- to three-fold increase in serum LH, attaining the peak at 20 min. The PRL concentration in the female 20 min-2 h after the injection was significantly lower than in the saline-injected rat. In the male rat, naloxone caused a decrease in the PRL concentration in the late afternoon when a small rise occurred in the saline-injected rat, although it caused no immediate changes. In addition to these hypophysiotropic effects, naloxone injected in the MPO and DBB unexpectedly had seizurogenic actions. More than 40% of the animals of both sexes given an injection of naloxone had behavioral seizures, which began after about 20 min and were repeated intermittently at 15-20 min intervals through the sampling period of 6 h. In the LH and PRL response to naloxone, there was no significant difference between animals with and without seizure response in both sexes. The results suggest that in the preoptic opioid system there is no difference according to sex in the control of LH, and only a small one, if any, in the control of PRL. Further, on the basis of previous reports, there is a GABAergic system in the preoptic region, that is antagonized by naloxone and causes the activation of cortical neuronal activity.

Animals↗
PubMed1990

Naloxone affects the luteinizing hormone secretory pattern in the short- and long-term ovariectomized rat.

The effect of naloxone, an opiate receptor antagonist, on the secretory pattern of luteinizing hormone (LH) was evaluated in 4-, 16- and 32-week ovariectomized (OVX) rats. Freely moving rats bearing cardiac cannulae were bled every 6 min for 3 h. During the first 90 min of bleeding, an equal volume of saline was injected after withdrawal of each blood sample, while during the second 90 min the replacement was done with saline containing naloxone at a dose of 0.5 (lower dose) or 1.0 (higher dose) mg/kg/h; statistical comparison was done between both treatment periods. In 4-week OVX rats, a significant increase in the mean LH level was observed through the 90-min period of lower-dose naloxone treatment, without significant changes in the pulse frequency and amplitude. In 4-week OVX rats treated with the higher dose and in 16-week OVX rats treated with either the lower or the higher dose, a significant elevation in mean LH levels was observed only during the first 30 min of treatment, which was probably related to the first, large LH peak in the naloxone treatment period. However, together with pulses appearing later in the treatment period, no significant changes were found in the LH pulsatility except for a decrease in frequency in 4-week OVX rats. In 32-week OVX rats, even the lower-dose naloxone did not induce an elevation in mean LH levels. The results demonstrate that naloxone can increase the LH secretion in the absence of ovarian hormones, and further that the effect on LH changes depending upon the dose of naloxone and the time after ovariectomy.

Animals↗
PubMed1989

Two cases of cystic fibrosis in Japanese children: studies on the essential fatty acid and prostaglandin metabolism.

We describe the fatty acid (FA) and prostaglandin (PG) metabolism in two Japanese cases of cystic fibrosis (CF) with or without pancreatic insufficiency (PI). The diagnosis of CF was based on the elevated sweat chloride concentration by pilocarpine iontophoresis. A 1-month-old boy (case 1) showed poor weight gain, steatorrhea and scaly dermatitis, but no respiratory symptoms were noted. He had decreased levels of serum linoleate and arachidonate, and increased palmitoleate and oleate levels, indicating essential fatty acid (EFA) deficiency. Supplementation of fat-emulsion improved his skin lesions and the altered FA pattern within a few months, associated with the definite reduction of the urinary PG F2 alpha levels. Until two years of age, he has been free from respiratory symptoms. A 12-year-old girl (case 2) had had recurrent respiratory tract infections due to Pseudomonas aeruginosa and Staphylococcus aureus for several years, and her pancreatic functions were preserved. The FA patterns of her serum lipid were almost within the normal range. These results indicate that 1) the altered FA composition appeared to be a secondary consequence of PI commonly complicating CF and 2) the correction of the altered FA and PG metabolism might have a beneficial effect on the respiratory function of CF patients with EFA deficiency.

Child↗
PubMed1989

[Geographic localization of three variants of herpes simplex virus type 1 in Japan].

We previously reported that a variant of herpes simplex virus type 1 (HSV-1) designated variant type A was isolated at a much higher frequency in Western Japan than in Eastern Japan. We examined the localization of two other variant types designated B and C. The proportion of the type B and type C variants among 553 fresh HSV-1 isolates from 10 areas in Japan were 5.4% and 1.3%, respectively. The isolation frequency of type B variant in Eastern Japan was 8.3%. It was as high as 20.5% in Iwate area. The frequency in Western Japan was only 3.0%. Type C variant showed no specific geographic localization. These results were discussed in terms of characteristic mode of HSV infection and the history of the Japanese nation.

Genetic Variation↗
PubMed1989

LHRH injected into the medial preoptic area potentiates LH secretion in ovariectomized estrogen-primed and proestrous rats.

To determine if luteinizing hormone releasing hormone (LHRH) might act within the central nervous system to modulate its own secretion, microinjection of LHRH into the medial preoptic area (MPO) was performed at 13:00 h in both the ovariectomized estrogen-primed and proestrous rat, and the effects on the afternoon rise in the serum concentration of luteinizing hormone (LH) were studied. Microinjection of 5 ng LHRH into the MPO in the ovariectomized estrogen-primed rat resulted in a significant increase in serum LH from 16:00 to 19:00 h compared to the value in the saline-injected rat, whereas the injection at a dose of 2 ng did not induce a significant change. The injection of 5 ng LHRH into the third ventricle in the ovariectomized estrogen-primed rat induced a transient increase in serum LH immediately after the injection, followed by recovery to the preinjection concentration by 1 h, indicating that the potentiating effect of 5 ng LHRH in the MPO was not due to the LHRH leaked into the third ventricle. Finally, microinjection of 5 ng LHRH in the proestrous rat induced an early increase in serum LH, resulting in an advancement of the peak of the afternoon rise by 1 h. It is suggested that LHRH secreted in the MPO may, directly or indirectly, stimulate its own secretion in the median eminence to produce the surge of LH secretion.

Animals↗
PubMed1988

Intraventricular injection of antiserum to nerve growth factor delays the development of amygdaloid kindling.

To investigate the possibility that nerve growth factor (NGF) may play some role in the development of kindling, rabbit anti-NGF serum was injected into the third ventricle on the first 3 days of daily electrical stimulation of the basolateral amygdala. The number of stimulations required to reach full amygdaloid kindling increased significantly in the rat injected with anti-NGF serum compared to that in the rat injected with normal rabbit serum. It was confirmed that anti-NGF serum did not act as an anticonvulsant. The results demonstrate that NGF may be important for the long-lasting neuronal changes induced by daily electrical stimulation of the amygdala.

Amygdala↗
PubMed1983

Subcostal 2-dimensional echocardiographic imaging of peripheral left coronary artery aneurysms in Kawasaki disease.

Our previous study provided a new 2-dimensional echocardiographic technique to detect peripheral right coronary artery aneurysms in Kawasaki disease, with use of the subcostal approach. An additional study was performed to detect peripheral left coronary artery aneurysms. Because the left anterior descending artery runs along the anterior interventricular sulcus and the left circumflex artery along the mitral valve ring, these regions were searched for coronary aneurysms by use of the subcostal imaging approach. Among 143 patients with Kawasaki disease, 44 left coronary aneurysms were visualized in 22 patients. Three aneurysms at the origin of the obtuse marginal artery and 1 in the further peripheral site of the left circumflex artery were observed in 3 patients. Two aneurysms at the origin of the second diagonal branch of the peripheral left anterior descending artery were detected. These echocardiographic studies were done prospectively, and their features coincided well in size, shape, and anatomic location with confirmatory angiographic appearances.

Aneurysm↗
PubMed1983

[Visualization of peripheral left coronary aneurysms in Kawasaki disease by subcostal two-dimensional echocardiography].

Our previous study provided a new two-dimensional echocardiographic technique for detecting peripheral "right" coronary artery aneurysms in Kawasaki disease using a subcostal approach. In the present paper, we presented an additional study for detecting peripheral "left" coronary artery aneurysms. Because the left anterior descending artery runs along the anterior interventricular sulcus and the left circumflex artery around the mitral valve ring, both coronary regions are difficult to search by a conventional method. Then coronary aneurysms of these regions were searched using the subcostal approach in this study. First, the sector beam was directed toward the heart on a plane parallel to a line between the patient's shoulders which allowed simultaneous visualization of four chambers (P1). The area around the mitral valve ring in this plane was examined for coronary aneurysms of the peripheral left circumflex artery. Secondary, the beam section was positioned parallel to the line cutting both the long axes of the sternum and spinal column which allowed visualization of the right ventricular outflow tract, pulmonary valves, interventricular septum, mitral valves and left atrium (P2). Thirdly, the sector plane was angled to the left (P3), and still more to the left (P4) until the left atrium just disappeared. By scanning from P2 to P4, the area around the mitral valve ring was examined for coronary aneurysms of the peripheral left circumflex artery. By scanning from P4 to the cardiac apex (P5), the anterior interventricular sulcus was searched for coronary aneurysms of the peripheral left anterior descending artery. Of 143 patients with Kawasaki disease, aged two months to 8 years, 7 peripheral left coronary aneurysms were visualized in five patients. These were three aneurysms in the left circumflex artery at the origin of the obtuse marginal artery, two aneurysms in segment 13, and two aneurysms in the left anterior descending artery at the origin of the second diagonal branch. These echocardiographic features coincided well in size, shape and anatomic location with angiographic appearances. In one patient whose echocardiogram in sector P2 showed a small echo-free space (2 X 2 mm) at the area around the mitral valve ring, the angiographic study showed the intact left circumflex artery, suggesting that there was a limitation to distinguish a very small coronary aneurysm from a normal one. There was no false negative diagnosis. These results showed that this new echocardiographic technique is useful for detecting peripheral left coronary aneurysms in patients with Kawasaki disease.

Aneurysm↗
PubMed1982

Subcostal two-dimensional echocardiographic imaging of peripheral right coronary artery in Kawasaki disease.

A new two-dimensional echocardiographic technique was developed to detect peripheral right coronary aneurysms in Kawasaki disease. Because the main stem of the right coronary artery runs along the tricuspid valve ring and the posterior interventricular groove, these regions were examined for coronary aneurysms using the subcostal approach. Of 52 patients with Kawasaki disease, 14 right coronary aneurysms were visualized in eight patients. Most of the coronary aneurysms were elicited as circular or oval echo-free spaces on the right side of the right ventricle or at the area around the tricuspid valve ring. These echocardiographic features coincided well in size, shape and anatomic position with angiographic appearances. The subcostal approach could not image the normal coronary artery. In three patients whose echocardiograms showed no abnormal echo-free space, the angiographic studies proved that the right coronary arteries were intact. These results suggest that this echocardiographic technique is useful for detecting peripheral right coronary aneurysms in patients with Kawasaki disease.

Aneurysm↗
PubMed1981

Echocardiographic visualization of ventricular septal defect in infants and assessment of hemodynamic status using a contrast technique. Comparison of M-mode and two-dimensional imaging.

Twenty-seven patients with ventricular septal defect (VSD), ages 2 months to 2 years, were evaluated by both M-mode and two-dimensional echocardiography (2-D echo) with the aid of a peripheral venous contrast technique. M-mode echocardiography was unreliable for imaging VSD. Using 2-D echo, defects in the interventricular septum were visualized in all patients examined; defects in the membranous portion (24 patients) were visualized by the subcostal frontal approach and defects in the supracristal portion (three patients) by the subcostal sagittal approach. The 2-D echo contrast study revealed negative contrast jets appearing through the defect in the right ventricle in 22 patients with a pulmonary-to-systemic blood flow ratio greater than 2.0, and positive contrast jets appearing through the defect in the left ventricle in 13 patients with a right-to-left ventricular peak pressure ratio greater than 0.71. We conclude that 2-D echo with peripheral contrast technique confirmed the anatomic location of VSD and indicated the approximate right-to-left ventricular peak pressure ratio, showing the contrast material shunting through the defect itself.

Cardiac Catheterization↗
PubMed1980

Subxiphoid cross-sectional echocardiographic imaging of the "goose-neck" deformity in endocardial cushion defect.

The cross-sectional echocardiographic demonstration of the "goose-neck" deformity is described in four patients with endocardial cushion defect. The diagnosis was confirmed in each patient by left ventricular angiocardiogram. The subxiphoid approach of cross-sectional echocardiography in diastole allowed visualization of an elongated, narrowed, and somewhat horizontally inclined configuration of the left ventricular outflow tract, which appeared almost identical to that obtained by angiocardiography. In systole, the right border of the left ventricle was composed of the cleft anterior mitral leaflet, the left-sided line of which was convex toward the left ventricular cavity. The mitral valvular echoes were thickened, jagged and irregular, which seemed to correspond to the scalloped appearance of the right border of the left ventricular silhouette in a systolic phase of the left ventricular angiocardiogram. There were no obvious differences between the goose-neck configuration of complete-type endocardial cushion defect and that of ostium primum atrial septal defect.

Echocardiography↗
PubMed1979

Mucocutaneous lymph node syndrome. A cross-sectional echocardiographic diagnosis of coronary aneurysms.

The cross-sectional echocardiographic technique for detecting coronary artery aneurysms of mucocutaneous lymph node syndrome (MLNS) was examined. When cutting the aortic root in round slices by the echocardiographic scanner, each of the right and left coronary arteries was imaged as a linear echo-free structure arising from the aortic root. Of 22 normal subjects, the left main coronary artery was imaged in all, the anterior descending branch in 18, the circumflex branch in six, and the right coronary artery in 18. Of 41 patients with MLNS, coronary artery aneurysms were detected as large echo-free spaces in four patients who were proved later to have these lesions by coronary angiography or autopsy. In addition, in four patients, whose echocardiograms demonstrated the coronary arteries to be normal, the angiographic studies showed that the coronary arteries were intact. These results suggest that the cross-sectional echocardiographic technique is a useful noninvasive diagnostic method for imaging the coronary arteries and the aneurysms in MLNS.

Aneurysm↗
PubMed1977

Cholesterol side-chain cleavage enzyme activity and cytochrome P-450 content in adrenal mitochondria of a patient with congenital lipoid adrenal hyperplasia (Prader disease).

An autopsied case with congenital lipoid adrenal hyperplasia (Prader disease) was presented. The cholesterol side-chain cleavage (SCC) enzyme activity in adrenal mitochondria of this case was assayed with [3H]cholesterol as substrate, combined with purified bovine adrenodoxin and adrenodoxin reductase, by measuring the amount of [3H]pregnenolone formed. The cytochrome P-450 content was also measured by recording the difference absorption spectra of carbon monoxide-complexed P-450. The cholesterol SCC enzyme activity in adrenal mitochondria of Prader disease was 0.81 nmol pregnenolone/nmol P-450 per min, which was approximately 10% of that in normal tissue. The content of cytochrome P-450 was 0.074 nmol/mg protein, which was about half of that in controls. These results indicate that there is a cholesterol SCC enzyme deficiency in adrenal mitochondria in this disease.

Adrenal Glands↗