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S Honma

Publications and source records attributed to S Honma.

At least 235 records · Page 13Linked to original sources
PubMed1984

Maternal phase setting of fetal circadian oscillation underlying the plasma corticosterone rhythm in rats.

We examined the entraining effect of the maternal circadian system on the fetal circadian oscillation during pregnancy. The circadian rhythm of locomotor activity and plasma corticosterone of pregnant rats was abolished by bilateral ablation of the suprachiasmatic nuclei at day 10 of gestation. At term, pups were removed by Cesarean section and were blinded immediately. To avoid possible rhythmic influences of a nursing mother on the pups' circadian rhythms, alternating nursing was imposed on blinded infants. Thus, pups were exchanged every 12 h between two foster mothers, one entrained to a light-dark cycle and the other to dark-light, so that one group of pups were always nursed in the light period and the other in the dark. Both groups of pups showed free-running circadian hormone rhythms with similar phase angles. However, the circadian rhythm of these pups was always phase delayed by about 8 h to that of blinded control pups which were born to unoperated mothers. Furthermore, blinded pups born to and nursed by a suprachiasmatic nuclei lesioned mother developed a circadian hormone rhythm which was phase delayed by 4 h to that of the control. It is concluded that the circadian oscillation underlying the rhythm of corticosterone release in rats has entrained to the maternal circadian system during fetal life. It is further suggested that the entrainment starts before day 10 of gestation.

Animals↗
PubMed1984

[Clinical effects of human fibroblast interferon in advanced gynecological cancers].

Human fibroblast interferon (IFN-beta) was given 13 cases of advanced gynecological cancers. Eight patients, who were clinically evaluable, were reported as follows; Patients consisted of ovarian adenocarcinoma (5), cervical adenocarcinoma (1), endometrial carcinoma (1) and tubal carcinoma (1). Route of administration was intravenous in 5 cases and intratumorous in 3 cases. IFN-beta dose ranged from 2, 650 X 10(4) to 10, 620 X 10(4) units. Clinical effects according to Koyama - Saitoh 's category was progressive disease (PD) in 7 cases and minor response (MR) only in one case who received intratumorous injection for recurrent tumor mass of tubal carcinoma in vaginal stump. Side effects of IFN-beta were chill and fever, fatigue and anorexia, leucocyte--and thrombocyte-- penia and hepatic dysfunction, though they were mild in grade and not dose-limiting factors. No anti-IFN-beta-antibodies were detected in any cases.

Adenocarcinoma↗
PubMed1983

Ontogeny of an oscillation underlying the circadian rhythm of plasma corticosterone in rats.

In previous reports (J. Physiol. 325, 493, 507, 521, 1982) we have suggested a prenatal onset of the circadian oscillation in rats. This was based mainly on the findings obtained in pups which were reared by an alternating nursing. In the present study we have applied this technique to experiments which were designed to determine the stage of gestation in the original mother that decided the phase angle of pup's hormone rhythm which was to develop later in the postnatal life. In this experiment we observed, though preliminarily, that reversal of the light-dark cycle of the pregnant mother at day 10 of pregnancy resulted in an effective reversal of pup's hormone rhythm, whereas the reversal at day 17 of pregnancy failed to affect it. From these results it is surmised that the original mother primarily determined the phase angle of the circadian oscillation in the fetus prior to the 17th day of gestation.

Aging↗
PubMed1983

Critical role of food amount for prefeeding corticosterone peak in rats.

The effects of food on plasma corticosterone levels were examined in rats under restricted daily feeding or prolonged food deprivation. High hormone levels before feeding were observed when the daily meal was restricted to 2 h at a fixed time of day, but it was not detected when food availability was extended to 6 h. The amount of food intake under the latter condition was comparable to that in 24 h of ad libitum feeding. After the termination of restricted feeding, the prefeeding hormone peak was maintained in rats fasted subsequently but disappeared when rats were returned to ad libitum feeding. Food deprivation for 10 days increased plasma corticosterone levels in the light period, resulting in abolition of the circadian rhythm. A subsequent meal decreased the hormone level such that the 24-h mean hormone level after food ingestion was inversely related to the amount of food intake. When rats were allowed to feed for 6 h after prolonged food deprivation, the prefeeding hormone peak observed at the second meal disappeared at the fourth meal. The amount of food consumption in these rats increased and reached a level comparable to that with ad libitum feeding at the third meal. It is concluded that the amount of food intake is critical for the development and maintenance of the prefeeding hormone peak under restricted feeding; prolonged fasting.

Animals↗
PubMed1983

[Inhibitory effects of OK-432 and PSK on cell growth of in vitro human choriocarcinoma cell lines].

The cancer chemotherapy combined with immuno-potentiators, OK-432 and/or PSK, had yielded an improvement in survival rate of choriocarcinoma patients in our clinic as previously reported elsewhere. In the present study, for the purpose of evaluation of direct antitumor activity of OK-432 and PSK, inhibitory effects of the drugs on cell growth of GCH-1 and GCH-2 (in vitro cell lines of human choriocarcinoma) were analyzed referring to those of MTX (methotrexate) and Act-D (actinomycin D). 1) IC 50 (50% inhibitory concentration) of OK-432 and of PSK were 0.56 KE/ml on GCH-1 and 0.48 KE/ml on GCH-2, and 310 micrograms/ml on GCH-1 and 460 micrograms/ml on GCH-2, respectively. 2) The morphological changes of the target cells, observed by light and electron microscope, induced by OK-432 and PSK seemed to be not different from those by MTX and Act-D. 3) Serial changes of hCG levels in the culture media in which OK-432 or PSK was added were roughly comparable with those in MTX or Act-D. Thus, the direct antitumor activity of OK-432 and PSK on GCH-1 and GCH-2 was exquisitely weak judging from their IC50 and it was suggested that their direct antitumor effects in vivo might be clinically negligible in choriocarcinoma.

Animals↗
PubMed1982

Pleural free cells in the mouse: quantitative and qualitative cell morphology.

Free cells in the pleural cavity of the mouse were studied by quantitative and qualitative morphological procedures. The size distribution curve of the cells, obtained by a Coulter counter and channelyzer, indicated that the pleural free cells were composed mainly of two populations, which were morphologically classified into small and large types. The small cells were about twice as numerous in females as in males, and the large type of cells exhibited no significant difference in number between the two sexes. Therefore, the total number of pleural cells was significantly greater in females than in males. The small pleural cells were similar in cytological features to the peritoneal medium-sized mononuclear cells described in previous papers (Abe et al., 1979a, b) with the exception of their size. Typical small lymphocytes were also included among the small type of pleural cells, but they were very few in number. The large type pleural cells were macrophages. The pleural macrophages were somewhat variable in cell features, particularly in surface configuration, as compared with peritoneal macrophages.

Animals↗
PubMed1981

Duration and selectivity in beta-adrenoceptor blocking action of a beta-adrenoceptor blocking drug, D-32 in conscious dogs.

In conscious dogs, the selectivity and duration of beta-blocking activity, and serum concentration of a beta-blocking agent, D-32 [dl-1-tert-butylamino-3-(2,3-dimethylphenoxy)-2-propanol hydrochloride] was compared to that of propranolol, pindolol, atenolol and IPS-339 [dl-1-tert-butylamino-3-(-9-fluorenylideneaminoxy)-2-propanol hydrochloride]. Ratios of doses causing a 50% inhibition of tachycardia to that on hypotension induced by isoprenaline were as follows: D-32 (0.69), propranolol (0.67), atenolol (0.03) and IPS-339 (6.3). Thus, present experiments indicate that, unlike atenolol and IPS-339, D-32, propranolol and pindolol are non-selective beta-adrenoceptor blocking agents. Atenolol and IPS-339, however, selectively blocked cardiac beta1, receptors and vascular beta2-receptors respectively, as would be expected. In an optimal dose range these two drugs can be used satisfactorily as a pharmacological tool for inhibiting responses mediated via the respective beta-receptors. After oral administration, the pharmacological half-life (time required for 50% recovery of beta-blocking action) was 15.8 +/- 4.5 h for propranolol (3 mg/kg), 21.8 +/- 6.4 h for D-32 (0.5 mg/kg), 30.5 +/- 3.1 h for atenolol (6 mg/kg) and 30-35 h for pindolol (0.2 mg/kg). The pharmacological half-life after i.v. administration was 4.4 +/- 0.7 h for propranolol (300 microgram/kg) and 5.9 +/- 0.4 h for D-32 (150 microgram/kg), whereas the serum half-like (time required for 50% decrease in serum concentration) of propranolol was 1.4 h and that of D-32 was 1.3 h. The values for pharmacological half-life and serum half-life were significantly different. Thus, for determination of administration frequency and dosage of beta-adrenoceptor blocking drugs, not only pharmacokinetic but also pharmacological data (duration of action) are essential.

Adrenergic beta-Antagonists↗
PubMed1981

Effects of hydrocortisone on peritoneal free cells in mice.

Effects of hydrocortisone on peritoneal free cells in the mouse were examined by quantitative morphologic procedures. Mice of both sexes at 60 to 65 days of age received one, two, or four successive subcutaneous injections of 0.5 mg hydrocortisone every 24 hrs. After one injection, peritoneal free cells showed a rapid decrease in number during the first 3 hrs. They then increased up to about 1.5 times the control value at 24 hrs and returned to the normal level at 48 hrs in both sexes. After two injections, peritoneal cells showed a significant decrease in number in females during the first 2 days. Thereafter they returned to normal in both sexes at 8 to 12 days. The three major types of peritoneal cells, type I, II and III cells, which have been described in previous papers (ABE et al., 1979a, b; HONMA et al., 1980), differed in response to hydrocortisone. Type I cells (small lymphocytes) were markedly reduced in number immediately after hydrocortisone injection and remained depleted even 12 days after injection. Type II cells (medium-sized mononuclear cells) showed the most remarkable response to hydrocortisone. Changes in the total number of peritoneal cells following hydrocortisone injection were ascribed mainly to those of type II cells. Type III cells (macrophages) did not show any significant changes in number after injection.

Animals↗