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H Ono

Publications and source records attributed to H Ono.

At least 541 records · Page 30Linked to original sources
PubMed1986

Spinal reflexes in chinoform-administered rats.

We examined the effects of chinoform (CF) on the spinal reflexes and the descending influences on the spinal reflexes from the locus coeruleus (LC) and the nucleus raphe magnus (NRM) in rats. The spinal reflex potential was recorded from the L5 ventral root following stimulation of the L5 dorsal root, and the effects of electrical stimulation of the LC and the NRM were tested in anesthetized rats. CF was suspended in Tween 80 and administered for two days (400 mg/kg, i. p./day) before the measurement of the spinal reflexes. In all rats treated with CF, death or motor incoordinations such as abnormal gait and hindlimb ataxia were observed. However, the control and CF-treated groups are not different in the amplitude and shape of the reflexes and in the influences of the LC and the NRM on the reflexes from the LC and the NRM. These results suggest that segmental spinal reflexes and descending influences from the LC and the NRM are not affected in rats suffered from motor incoordination by acute CF.

Animals↗
PubMed1986

Alpha 2-adrenergic receptors on canine platelet membranes characterized by [3H]-yohimbine binding.

Alpha 2-adrenoceptors on canine platelet membranes were characterized by [3H]-yohimbine binding. Binding of [3H]-yohimbine to the membranes was rapidly saturated, stable and reversible with high affinity. Dissociation constant (KD) calculated from Scatchard analysis of the equilibrium experiments was 1.89 +/- 0.20 nM which was in good agreement with KD (1.97 +/- 0.60 nM) obtained in the kinetic experiments. Maximal binding sites of the ligand (Bmax) was 249 +/- 20 fmoles/mg protein. Adrenergic antagonists inhibited the ligand binding in following rank order of potency; yohimbine greater than phentolamine greater than phenoxybenzamine greater than corynanthine greater than prazosin. This order was in good correlation with that for these drugs in the inhibition of platelet aggregation. Hill coefficients for the displacement curves of the ligand binding by adrenergic agonists were less than 1.0 which were converted into near unity in the presence of 5'-guanylyl-imidodiphosphate (100 microM). These results demonstrate that canine platelet membranes have alpha 2-adrenoceptors and suggest that the binding of these receptors to adrenergic agonists is regulated by guanine nucleotides.

Animals↗
PubMed1986

Papaverine inhibits binding of [3H]-prazosin and [3H]-yohimbine to rat renal cortical membranes.

We examined the effects of papaverine on specific [3H]-prazosin and [3H]-yohimbine bindings to rat renal cortical membranes and compared these effects with those of verapamil. Papaverine inhibited both ligand bindings with KI values of 4.2 +/- 1.7 microM and 48.4 +/- 8.7 microM (N = 5) in the inhibition of [3H]-prazosin and [3H]-yohimbine bindings, respectively. In contrast with verapamil, which competitively inhibited both ligand bindings, papaverine inhibited them in a different manner. Although the affinities of these ligand binding sites for papaverine are low, alpha-receptor blockade is a possible mechanism of action of this compound.

Animals↗
PubMed1986

Two factors affecting saccadic amplitude during vergence: the location of the cyclopean eye and a left-right bias.

Saccades occurring during vergence have been reported to differ in amplitude depending on whether the saccade drives the eyes leftward or rightward. Furthermore, this difference varies in degree and direction among individuals. We examined two explanations of the variation--that it is the result of the cyclopean eye being nearer to one eye, and that it is the result of a pervasive bias, within an individual, to make larger saccades either leftward or rightward. Examination of the saccades of 14 subjects, recorded during both divergent and convergent movements that required leftward or rightward saccades, shows that neither explanation alone provides an adequate account of the differences observed. However, statistical analysis (ANOVA) indicates that almost 60% of the total variation in the observed saccadic amplitudes is related to the two explanations taken together. We speculate that both influences act on the saccade in a given individual, and that the amplitude manifested depends on the relative magnitudes of the two influences within that individual.

Accommodation, Ocular↗
PubMed1986

[Nonfunctioning adrenocortical carcinoma revealed by metastasis to the base of the tongue].

A 60-year-old man visited our clinic with the complaint of a tumor of the tongue base. Clinical and histological examination revealed that the tumor was metastasis from left adrenal carcinoma. Metastatic lesions were present in the tongue base, cervical lymph node and lung. There were no endocrinological abnormalities in the laboratory examination. The patient died about three months after admission. The autopsy disclosed nonfunctioning carcinoma of the adrenal cortex. Ninety-two cases of nonfunctioning adrenocortical carcinoma in Japan including the present patient are briefly reviewed.

Adenocarcinoma↗
PubMed1985

[The relationship between changes of the steroid receptor and synchronization in human adenocarcinoma cells in vitro of the endometrium].

We investigated the G1 and S phases of synchronization using sodium n-butyrate, MTX and excess thymidine. The flow cytometry system was employed for cell cycle analysis while the receptor assay was adopted dextran coated charcoal (DCC) and the wash method. The results were as follows: S phase synchronization by MTX was 138% (control 100%) and by excess thymidine in the block and release method 210%. G1 phase synchronization by sodium n-butyrate was 140%. The progesterone receptor level, by E2 priming increased to 1.45 fmol/ug DNA being more than five times that of the control PR. The estrogen receptor level increased to 18.29 fmol/ug DNA in the G1 phase synchronization, seven times that of the control ER. From this study, the functional increase of the steroid receptor was most significant in the G1 phase.

Adenocarcinoma↗
PubMed1985

Translocation of proteins into rat liver mitochondria. Existence of two different precursor polypeptides of liver fumarase and import of the precursor into mitochondria.

Two different putative precursor polypeptides of rat liver fumarase were synthesized when RNA prepared from rat liver were translated in vitro using the rabbit reticulocyte lysate system. One of these putative precursor polypeptides (P1) was synthesized as a larger molecular mass than the mature subunit of fumarase (45,000 daltons) by about 5,000 daltons and the other (P2) had the same molecular mass as the mature enzyme. When the 35S-labeled cell-free translation products were incubated with rat liver mitochondria at 30 degrees C, P1 and the 35S-labeled mature size fumarase were associated with the mitochondria. Of these, the 35S-labeled mature size fumarase was resistant to externally added protease, but P1 was not, indicating that the 35S-labeled mature size fumarase was located in the mitochondrial matrix. The following observations strongly suggested that the 35S-labeled mature size fumarase in mitochondria was derived from P1, which was energy-dependently imported and concomitantly processed to the mature size. 1) The amount of the 35S-labeled mature size fumarase recovered from the mitochondria increased proportionally to the duration of incubation, while the amount of P1 recovered from the post-mitochondrial and mitochondrial fractions decreased with the duration of the incubation. 2) Only P1 could bind with the mitochondrial outer membrane at 0 degrees C even in the presence of an uncoupler of the oxidative phosphorylation but P2 did not. 3) P1 bound to the mitochondrial outer membrane was imported into the matrix, when the mitochondria binding only P1 at 0 degrees C was reisolated and incubated at 30 degrees C in the presence of an energy-generating system. The specific receptor was involved in the binding of P1 to mitochondria, since a high concentration of NaCl did not interfere with the binding of P1 to the membrane and did not discharge P1 bound onto the membrane. It was shown that P1 formed an aggregate composed of 6 to 8 molecules and P2 was a dimer in the cell-free translation mixture and that P1 and P2 were enzymatically inactive. These results suggest that the precursor for the mitochondrial enzyme has a larger molecular weight than that of the mature enzyme, whereas the precursor for the cytosolic enzyme has the same molecular weight as the mature enzyme.

Animals↗