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M Hotta

Publications and source records attributed to M Hotta.

At least 73 records · Page 4Linked to original sources
PubMed1993

Intracerebroventricular administration of corticotropin-releasing factor induces c-fos mRNA expression in brain regions related to stress responses: comparison with pattern of c-fos mRNA induction after stress.

Centrally administered corticotropin-releasing factor (CRF) produces a number of physiological and behavioral changes akin to those elicited by exposure to acute stress. However, the specific brain site of action responsible for the centrally activating property of CRF has not been precisely determined. In this study, we used in situ hybridization histochemistry for c-fos mRNA to map potential neuronal structures activated after intracerebroventricular (i.c.v.) injection of CRF and compared the distribution of c-fos mRNA with that after stress. Wistar male rats were sacrificed 30, 60, 120 and 180 min after the i.c.v. injection of 1 microgram ovine CRF or vehicle alone. Another group of rats was exposed to immobilization stress for 60 min or electrical foot-shock stress (1.5 mA, 1-s duration, 30 x) for 15 min and sacrificed before and 30, 60, 120 and 180 min after the beginning of stress. Centrally administered CRF rapidly (30-60 min) induced c-fos mRNA expression in most of the areas that showed hybridization signals for c-fos after stress: the limbic structures, including the piriform cortex, cingulate cortex, the lateral septal nucleus, the hippocampus, the anterior corticomedial and the medial amygdaloid nuclei, the hypothalamic nuclei, such as the paraventricular nucleus, the supraoptic nucleus (SO) and the dorsomedial nucleus (DMD), and some brainstem nuclei like the pontine nucleus, the locus ceruleus (LC) and Barrington's nucleus. The granular layer of the cerebellum, some thalamic nuclei and the habenula also showed hybridization signals after i.c.v. injection of CRF and stress. However, c-fos induction in the bed nucleus of the stria terminalis, the central nucleus of the amygdala (CeA) and the nucleus tractus solitarius (SOL) was seen only after i.c.v. administration of CRF; in the septo-hypothalamic nucleus and the superior olive, however, c-fos mRNA expression was observed only after stress. There were no differences in the pattern of c-fos mRNA expression between the two stress paradigms. In contrast, i.c.v. injection of saline-induced expression of c-fos mRNA in the piriform cortex, neocortex, cingulate cortex and the amygdala was much less than that seen after i.c.v.-administered CRF as evident in the intensity of the signals. These results suggest that CRF produces c-fos mRNA expression in the brain areas related to stress response, and that CRF may induce behavioral and neuroendocrine responses through activating these brain structures, such as the limbic system and the hypothalamic nuclei.(ABSTRACT TRUNCATED AT 400 WORDS)

Analysis of Variance↗
PubMed1993

Low-dose/long-term erythromycin for treatment of bronchiolitis obliterans organizing pneumonia (BOOP).

Bronchiolitis obliterans organizing pneumonia (BOOP) is a pathologic entity characterized by intraluminal fibrosis of distal air spaces. Corticosteroids have been widely used for the treatment of this condition, and most patients showed a dramatic response to it. However, long-term treatment with corticosteroids, which often increases the risk of several undesirable side-effects, is usually required because a relapse tends to occur soon after termination of treatment. We administered erythromycin (EM) at low-dose (600 mg daily) for 3-4 months to 6 patients with BOOP, and obtained a good clinical, radiological, and physiological improvement. This suggests that EM can be successfully used, instead of corticosteroids, in the treatment of BOOP.

Adolescent↗
PubMed1992

Early induction of c-fos precedes increased expression of corticotropin-releasing factor messenger ribonucleic acid in the paraventricular nucleus after immobilization stress.

CRF plays a role in coordinating endocrine, physiological, and behavioral responses to stressful stimuli. Several kinds of stressors have been reported to induce an increase in CRF mRNA expression in the paraventricular nucleus of the hypothalamus (PVN). Recently, the expression of c-fos mRNA has shown promise as a useful tool for metabolic mapping at the cellular level, because various types of stimulation induce c-fos mRNA expression in specific neuron populations in various brain regions. The aim of the present study is to clarify a possible anatomical-temporal correlation between the early induction of c-fos and the enhanced expression of CRF mRNA after stress. Wistar male rats were exposed to immobilization stress for 60 min and killed before and 15, 30, 60, 90, 120, and 180 min after the beginning of immobilization. In situ hybridization was performed by hybridizing sections with 35S-labeled prepro-CRF and c-fos cRNA probes. Relative levels of CRF and c-fos mRNA were compared by estimating the number of grains over the PVN in emulsion-dipped autoradiograms. Rapid induction (within 15 min) of c-fos mRNA was noted in the parvocellular division of the PVN after immobilization stress. The level of c-fos mRNA peaked at 30 min, then gradually declined to the control level within 90 min after the beginning of stress [the number of grains over the PVN: control, 326 +/- 180; 15 min, 2091 +/- 680 (P less than 0.05 vs. control); 30 min, 3385 +/- 239 (P less than 0.05 vs. control)]. The distribution of c-fos mRNA was almost identical to that of CRF mRNA in the PVN. On the other hand, the time course of CRF mRNA induction was delayed to the c-fos mRNA expression. A significant increase in CRF mRNA levels was noted only 120 and 180 min after stress [the number of grains over PVN: control, 3868 +/- 221; 120 min, 5957 +/- 677 (P less than 0.05 vs. control); 180 min, 6600 +/- 450 (P less than 0.05 vs. control)]. The results demonstrate that increased expression of CRF mRNA is preceded by c-fos mRNA induction in the PVN after stress suggesting a role of c-fos in the activation of CRF gene expression.

Animals↗
PubMed1992

[A case of hyperinsulinemia due to hypersecretion of incretin].

A 65-year-old male presented with postprandial hypoglycemic episodes. He had normal glucose tolerance, but plasma glucose reached a hypoglycemic level of 31 mg/dl at 120 min during 75 g oral glucose tolerance test. He had markedly increased insulin response to oral glucose but not to intravenous glucose, intravenous arginine or intravenous glucagon. Hyperresponse of insulin after oral but not intravenous glucose suggested the possible involvement of insulinotropic hormonal factor in the gut (incretin) in hyperinsulinemia of this patient. Therefore we evaluated the secretory response of glucagon like peptide-1 (GLP-1), a most likely candidate for incretin, to oral and intravenous glucose administration. Plasma GLP-1 response to oral glucose was almost five times greater than that of normal subjects. On the other hand, there was no significant response in plasma GLP-1 after intravenous glucose. These results suggest that hypersecretion of GLP-1 may be responsible for the hyperinsulinemia after oral glucose in this patient.

Aged↗
PubMed1992

[A case of bronchocentric granulomatosis associated with uveitis].

A 32-year-old female was admitted to our hospital because of abnormal pulmonary shadows and a decrease in visual acuity. Analysis of peripheral blood revealed eosinophilia, and chest roentgenogram demonstrated multiple infiltrates in the right upper lung field. Pathological examination of transbronchial lung biopsy specimens revealed necrotizing granulomatous lesions in the walls of bronchioles, and a definitive diagnosis of bronchocentric granulomatosis was made. The cause of bronchocentric granulomatosis in this patient was suggested to be an allergic reaction to Aspergillus because of positive response to skin test for Aspergillus. Although it is reported that extrapulmonary involvement is rare in bronchocentric granulomatosis, the present case was associated with uveitis, and to our knowledge is the first reported case.

Adult↗
PubMed1992

Pharmacokinetics of the new antiplatelet agent 2-methyl-3-(1,4,5,6-tetrahydronicotinoyl)pyrazolo[1,5-a]pyridine in laboratory animals.

KC-764 (2-methyl-3-(1,4,5,6-tetrahydronicotinoyl)pyrazolo [1,5-a]pyridine CAS 94457-09-7) and its metabolites in serum and urine were determined after intravenous and oral administration in mice, rats, rabbits and dogs at a dose of 5 mg/kg. KC-764 was rapidly eliminated from serum in all species. The biological half-lives of unchanged KC-764 after intravenous administration in mice, rats, rabbits and dogs were 1.31, 0.29, 1.94 and 1.20 h, respectively. 2-Methyl-3-(1,4,5,6-tetrahydro-6-oxonicotinoyl)pyrazolo-[1,5-a]pyr idine was a common major metabolite in serum of all species, although 6,7-dihydro-6,7-dihydroxy-2-methyl-3-(1,4,5,6- tetrahydro-6-oxonicotinoyl) pyrazolo-[1,5-a]pyridine (M-8) was more abundant in rabbits. Urinary recovery of unchanged KC-764 was as low as 0.4-2.2% in all species. The major urinary metabolite was 2-methyl-3-(1,4,5,6-tetrahydro-6-ureidonicotinoyl)pyrazolo-[1,5-a] pyridine in mice, rats and dogs, but M-8 was in rabbits. KC-764 was rapidly and well absorbed by oral administration, and extensively metabolized in all species tested.

Administration, Oral↗
PubMed1992

Pharmacokinetics of the new antiplatelet agent 2-methyl-3-(1,4,5,6-tetrahydronicotinoyl)pyrazolo[1,5-a]pyridine in human subjects.

The pharmacokinetics of KC-764 (2-methyl-3-(1,4,5,6-tetrahydronicotinoyl)pyrazolo[1,5-a]pyridine, CAS 94457-09-7) was studied in healthy male adult volunteers after single ascending oral dose and multiple dosing for 7 days. Serum KC-764 concentration attained the peak in 1 h and declined with a half-life of about 2 h at a single oral dose of 5, 10, 20 and 40 mg. No dose dependent pharmacokinetics of KC-764 was demonstrated. Three metabolites were detected in serum, but their concentrations were lower than that of KC-764. 48-h urinary recoveries after single doses were 41.6-46.6% of dose, not being dose-dependent. Urinary recovery of unchanged KC-764 was 1.1-1.6% of dose. Three metabolites were present in greater amount in urine than unchanged KC-764 and two metabolites were less than KC-764. There was little daily variation of serum concentrations and urinary excretion of KC-764 and its metabolites in the multiple dosing (20 mg twice a day) study. The daily and total urinary recovery were same as those after single doses. Food reduced Cmax and tended to delay tmax, but did not influence AUC0----infinity and urinary recovery. Serum protein binding of KC-764 was about 60%, being not dependent on total serum concentration.

Adult↗
PubMed1991

Brain corticotropin-releasing hormone increases arousal in stress.

The effect of restraint stress on pentobarbital-induced sleeping time was examined in rats. Restraint for 60 and 75 min significantly shortened pentobarbital-induced sleeping time. The shortening of sleeping time by restraint was completely reversed by intracerebroventricular (i.c.v.) administration of alpha-helical CRH(9-41), a corticotropin-releasing hormone (CRH) receptor antagonist. In conjunction with our previous finding that i.c.v. administration of CRH shortens pentobarbital-induced sleeping time, the results suggest that restraint stress increases arousal through brain CRH.

Animals↗
PubMed1991

Umbilical artery blood flow velocity waveforms in pregnancy complicated by diabetes mellitus.

Umbilical artery blood velocity waveforms were recorded by a pulsed Doppler system in the third trimester of pregnancy in 16 diabetic women (12 class B, 1 class C, 3 class D) and the waveforms were analysed for resistance index (RI = peak systolic velocity minus end diastolic velocity/peak systolic velocity). There was no significant correlation between the RI values and either serum glucose (r = 0.385) or fructosamine levels (r = 0.380). However, the RI values were raised in two cases with serum glucose levels of over 300 mg/dl. With a fall in serum glucose levels, the RI values returned to the normal range. No abnormal umbilical artery velocity waveforms were found when the serum glucose level was below 200 mg/dl.

Blood Flow Velocity↗
PubMed1991

The effects of chronic central administration of corticotropin-releasing factor on food intake, body weight, and hypothalamic-pituitary-adrenocortical hormones.

The effects of chronic central administration of corticotropin-releasing factor (CRF) on food intake, body weight, and hypothalamic-pituitary-adrenocortical hormones were investigated in rats. The infusion of ovine CRF at doses of 0.3 and 1.0 microgram/h continuously induced decrease in food intake and a suppression of body-weight gain for 7 days. The inhibition of body weight gain induced by CRF could not be accounted for solely by a decreased food intake since the suppression of body-weight gain in CRF-infused rats was significantly greater than that observed in rats which received the same amount of food as the CRF-infused rats. The content of proopiomelanocortin (POMC) -derived peptides in the anterior lobe of the pituitary as well as the plasma levels of ACTH and corticosterone (B) were significantly elevated in CRF-treated rats, and the CRF content in the hypothalamus was significantly decreased. These results suggest that chronic intracerebroventricular (icv) administration of CRF stimulates the synthesis and secretion of POMC-related peptides in the pituitary and suppresses food intake accompanied by inhibition of body weight gain. The results are similar to clinical and laboratory findings observed in patients with stress-induced anorexia.

Adrenocorticotropic Hormone↗
PubMed1991

Interleukin-1 inhibits stress-induced gastric erosion in rats.

The effect of interleukin (IL)-1 on the occurrence of stress-induced gastric erosions was examined in rats. The intracerebroventricular (icv) administration of IL-1 beta significantly inhibited the occurrence of water-immersion restraint stress-induced gastric erosion at doses of 200 ng, 500 ng and 1 microgram, whereas the intravenous (iv) administration of IL-1 beta altered the occurrence of gastric erosion only at a dose of 1 microgram. The inhibitory effect of IL-1 alpha icv administered on the occurrence of gastric erosion was found only at a dose of 1 microgram. The inhibitory effect of IL-1 beta icv administered on the occurrence of stress-induced gastric erosion was not influenced by icv administration of alpha-helical CRF(9-41), a corticotropin-releasing factor (CRF) receptor antagonist. Indomethacin completely blocked the inhibitory action of IL-1 beta icv administered on stress-induced gastric erosion. It is concluded from these results that IL-1 acts mainly in the central nervous system to inhibit the occurrence of stress-induced gastric erosion and that the IL-1 beta-induced inhibition of gastric erosion is mediated by prostaglandin in a manner that is independent of brain CRF.

Animals↗