Search PubMed⌕ Search

Biomedical subjects

K Aisaka

Publications and source records attributed to K Aisaka.

At least 91 records · Page 5Linked to original sources

General pharmacological studies on N-(2,6-dimethylphenyl)-8-pyrrolizidineacetamide hydrochloride hemihydrate. 3rd communication: effect on cardiovascular system.

In this general pharmacological study of N-[2,6-dimethylphenyl)-8-pyrrolizidineacetamide hydrochloride hemihydrate (SUN 1165), its effects on the cardiovascular and respiratory systems were studied. SUN 1165, at doses of up to 1.0 mg/kg i.v., had almost no effect. SUN 1165, at doses of 3.0 and 6.0 mg/kg i.v., caused dose-dependent decreases in blood pressure, common carotid, vertebral, coronary, hepatic and femoral artery and portal vein blood flows, cardiac contractility, heart rate and myocardial oxygen consumption. SUN 1165 increased urine volume and urinary excretion of electrolytes in rats at a dose of 100 mg/kg p.o. SUN 1165 decreased renal plasma flow and urinary excretion of electrolytes in anesthetized dogs at 6.0 mg/kg i.v., but at the antiarrhythmic doses (1.0-3.0 mg/kg i.v. in dogs), it had almost no effects on renal function. SUN 1165 had almost no effect on the autonomic nervous systems in anesthetized dogs. These results suggest that SUN 1165 at the antiarrhythmic doses do not have any effects on the respiratory and cardiovascular systems, renal function and autonomic nervous systems in rats and dogs, but that when administered at high doses, it has inhibitory effects on respiratory and cardiovascular system and renal function. In conclusion, SUN 1165 seems to be a novel antiarrhythmic drug relatively free of cardiovascular, respiratory, renal and autonomic effects.

Animals↗

[Effects of obesity and weight gain during pregnancy on obstetrical factors].

The relationship between the body weight or weight gain during pregnancy and various obstetrical factors was investigated in 731 patients who delivered in San-ikukai Hospital for in the year 1986. The patients were classified into three groups according to their body weight in non-pregnant states: slender (n = 214), ordinary (n = 379) and obese (n = 138), according to the standard for "The decision diagram for the estimation of obesity and emaciation in Japanese" published in 1986 by the Ministry of Health and Welfare, Japan. Each of these groups was further divided into two groups according to the degree of weight gain during pregnancy (more or less than 15kg). Then, the duration of labor, the blood loss during delivery, the birth weight, the placental weight and the obstetrical abnormalities (prolonged labor, arrested labor, blood loss of more than 500 ml, fetal distress and toxemia of pregnancy) were investigated in these groups. The blood loss, the neonatal birth weight and the placental weight in the obese groups were much greater than those in the ordinary or the slender group (p less than 0.005). However, there was no significant difference in the duration of the labor among these groups. The incidence of obstetrical abnormalities in the obese group was significantly higher than in the ordinary or the slender group (chi 2 = 4.37, p less than 0.05, chi 2 = 5.27, p less than 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗

[Role of TRH or metoclopramide loading test in the diagnosis of so-called occult or latent hyperprolactinemia].

Present study was performed to investigate whether TRH or metoclopramide (MCP) loading test was useful for the diagnosis of so-called occulted or latent hyperprolactinemia (transient increase of serum prolactin levels more than 30 ng/ml during night; OHP). The circadian profiles of serum prolactin levels were examined in 31 women (age: 23-32 years old) whose BBT charts showed biphasic patterns. Blood samplings had been done every two hours through an intravenous indwelling catheter without any disturbances. And seven cases of the OHP were selected. Five cases of the control were also selected at random. Then, LH-RH (100 micrograms) and TRH (500 micrograms) loading test and LH-RH and MCP (10 mg) loading test were performed to these cases in the mid-luteal phase of the same menstrual cycle at interval of two or three days, and serum FSH, LH and prolactin levels (at 0, 30, 60, 90, 120 min. after the loading test) were determined by radioimmunoassay. Serum prolactin levels in the OHP group showed significant higher levels than those of the control from 22 to 6 o'clock (p less than 0.05-0.005). By the administration of 500 micrograms of TRH, serum prolactin levels of the OHP group increased significantly compared to those of the control at all sampling points (p less than 0.05-0.005), and also by the administration of 10 mg of MCP, the same result was obtained (p less than 0.05-0.02). The maximum peak of serum prolactin levels appeared at 30 min. after TRH or MCP loading.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Clinical evaluation of the prolactin secreting capacity for the diagnosis of occult hyperprolactinemia].

To clarify the diagnostic criteria of occulted or transient hyperprolactinemia, the resting prolactin level and the prolactin secreting capacity of normal women, which were tested with a 500 micrograms of TRH injection, were compared with those of patients with occulted hyperprolactinemia. Results revealed that: resting levels of prolactin in normal women were 13.4 +/- 4.4 ng/ml (mean +/- S.D.) in the follicular phase and 13.4 +/- 5.6 ng/ml in the luteal phase, which overlapped those of occulted hyperprolactinemia. the prolactin secreting capacity of occulted hyperprolactinemia was significantly greater than that of the normal women. These results indicated that it was impossible to distinguish the occulted hyperprolactinemia from the normal by the measuring the resting prolactin level, but possible by the evaluating the prolactin secreting capacity. If the serum prolactin was more than 150 ng/ml at 15 min. after TRH administration, occulted hyperprolactinemia was strongly suggested.

Circadian Rhythm↗

Effects of sitting position on uterine activity during labor.

To determine which components of uterine activity are affected by different positions of labor, 116 intrauterine pressure records in the sitting and supine positions were analyzed in order to measure resting, contraction, and bearing down pressures. The resting pressure in the sitting position showed consistent elevation compared to the supine position, while the contraction pressure did not differ strikingly in the two positions. The bearing down pressure in the sitting position for nulliparas during the second stage and for multiparas at the time of the 8- to 10-cm dilation was significantly higher than that in the supine position. Also, the sitting position led to a significantly shorter duration of the second stage in nulliparas and the 5- to 10-cm dilation period in multiparas. These findings suggest that the maternal position does not affect uterine contractility, that the increased resting pressure in the sitting position is of some importance in supplementing the downward delivery force, and that the increased bearing down pressure in the sitting position could help to significantly shorten the duration of labor.

Female↗

[Studies on prolactin secreting capacity in the ovulatory infertile patients with transient hyperprolactinemia].

The changes in serum prolactin levels during the menstrual cycle have not been clarified yet. The present study was conducted to investigate whether the changes in serum prolactin levels during the menstrual cycle exist in ovulatory infertile patients having high prolactin release due to TRH administration described below (transient hyperprolactinemia) and control cases. Serum prolactin levels in both groups were less than 25 ng/ml at daytime. In the patients with transient hyperprolactinemia, serum prolactin levels showed more than 150 ng/ml at 30 min. after the administration of 500 micrograms of TRH, and those were less than 150 ng/ml in the normal control group. The daily changes of serum FSH, LH, prolactin, estradiol and progesterone levels were determined by radioimmunoassay in 6 cases of transient hyperprolactinemia and 5 controls which showed normal ovulatory cycles in the patterns of the BBT charts and other hormones. An estrogen feedback test was also carried out at the mid-luteal phase in 9 cases of transient hyperprolactinemia and the controls to determine serum levels of FSH, LH, prolactin and estradiol. In the patients with transient hyperprolactinemia, 5 mg of bromocriptine was administered every day for more than 30 days, and the effects of bromocriptine on the changes in serum gonadotropin levels by the estrogen feedback test were also analysed. Serum prolactin levels in the follicular, ovulatory and mid-luteal phases increased significantly in the patients with transient hyperprolactinemia, compared to the controls (p less than 0.005). The pattern of serum prolactin levels in the patients with transient hyperprolactinemia was almost synchronized with that of serum estradiol levels. There was also a significant correlation (r = 0.5782, p less than 0.005) between the prolactin and estradiol levels in the serum of the patients. The obvious change was not noted in serum prolactin levels during the menstrual cycle of the controls. No significant change in other hormones was observed during the cycle between these two groups. After the administration of estradiol benzoate (100 micrograms/kg), serum estradiol levels increased markedly, serum prolactin levels increased with the similar change in serum estradiol levels, and serum prolactin levels in the patients with transient hyperprolactinemia were significantly higher compared to those of the controls (p less than 0.01 approximately 0.005). The responses of serum gonadotropin levels by the administration of estradiol benzoate had good positive and negative feedback effects in the patients with transient hyperprolactinemia as well as those of the control group.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

[Effects of transient or occult hyperprolactinemia on luteal function].

It is well known that the luteal function in the patients with hyperprolactinemia is much suppressed by high level of serum prolactin. Present study was performed to investigate whether the luteal function in the patients with transient or occulted hyperprolactinemia was affected by the transient increase of serum prolactin level. The circadian changes of serum FSH, LH, prolactin, estrone, estradiol and progesterone levels were examined in seven cases of the transient or occulted hyperprolactinemia whose BBT charts showed biphasic patterns. Serum prolactin levels of these patients were less than 25 ng/ml at daytime and more than 150 ng/ml at 30 minutes after the administration of 500 micrograms of TRH. Blood samplings were taken every two hours through an intravenous indwelling catheter without any disturbances. All of the patients had their breakfast at 7 to 8, lunch at 11 to 12 and dinner at 17 to 18 o'clock and slept from 22 until 6 in the next morning. Serum FSH, LH, prolactin, estrone, estradiol and progesterone levels were determined by RIA and the circadian changes of these hormones were analysed. Then, 5 mg of bromocriptine was administered every day to these patients for more than 30 days and the duration of the luteal phase and the mid-luteal serum estradiol and progesterone levels for the indicators of the luteal function were examined before and after the administration of bromocriptine. The circadian changes of serum prolactin levels in the patients showed significant increase during both daytime and night compared to those of the control (p less than 0.005, p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Cervical teratoma in a fetus and an adult. Two case reports and review of literature.

Two cases of cervical teratoma in a 30-weeks fetus and a 26-year-old female have been presented. In the former case a large mass entirely occupied the anterior neck but showed no invasive or metastatic lesions, and in the other case a mass containing multiple cysts was situated in the right lower pole of the thyroid gland. Histologically, both tumors were composed of the elements derived from three germ layers including various epithelial components, cartilage, muscle, and adipose tissue. In addition to these predominantly mature elements, there were some elements showing primitive immature structure in the former case. Positive immunohistochemical staining for thyroglobulin displayed only in the former case and was observed in the compressed thyroid follicles located in the fibrous capsule and several small foci of primitive glandular structure which was an element of the tumor.

Adult↗

Cloning and constitutive expression of the N-acetylneuraminate lyase gene of Escherichia coli.

The N-acetylneuraminate (NANA) lyase (EC 4.1.3.3) gene from Escherichia coli was self-cloned in E. coli. Transformants were selected by complementation of a NANA lyase-deficient E. coli strain. One clone was found to produce NANA lyase, and it contained a recombinant plasmid, pNAL1, with a 9.0-kilobase HindIII insert. The cloning of the NANA lyase gene resulted in the change from inducible to constitutive production of the enzyme. The level of expression of the NANA lyase gene in E. coli(pNAL1) clones was two- to three-fold higher than that in the fully induced wild-type strains.

Cloning, Molecular↗

[Comprehensive approach to the clinical study of the administration of dehydroepiandrosterone-sulfate (DHA-S) during the induction of labor].

Effects of Dehydroepiandrosterone-Sulfate (DHA-S) administration during the induction of labor were analysed comprehensively in 116 cases of primipara without any complications. In all of the patients delivery was induced by means of intravenous drip infusion of oxytocin. DHA-S was given as follows; Group A: no administration of DHA-S, Group B: intravenous drip infusion of 600 mg of DHA-S, Group C: intravenous injection of 200 mg of DHA-S every two hours (max, five times). The duration of the first and second stages of labor was reduced significantly in Group C compared to that of Group A (p less than 0.02). Serum DHA-S and estradiol levels in the patients in Groups B and C were significantly higher than those in Group A during the induction of the labor (p less than 0.05-0.005). The secretion of maternal milk was suppressed transiently by the administration of DHA-S (p less than 0.05-0.005), and there was a significant negative correlation between the total amount of maternal milk secretion and the total dose of DHA-S (r = -0.6320, p less than 0.005). Maternal serum prolactin levels did not change significantly following the administration of DHA-S, but estradiol increased significantly following the administration of DHA-S until 48 hours after delivery. These facts suggested that the intravenous injection of 200mg of DHA-S every two hours was effective in assisting the induction of labor, and the transient suppression of maternal milk secretion due to the administration of DHA-S might be caused by the high level of maternal serum estradiol which was converted from DHA-S in the placenta.

Adult↗

[The effects of bromocriptine on the pulsatile pattern and the circadian profile of gonadotropins and testosterone secretion in normal adult men].

To investigate the effects of bromocriptine on the secretion mechanism of pituitary gonadotropins and testosterone, 5 mg of bromocriptine was administered to five young adult men who were normal in their endocrinological states. Blood samplings were taken from two hours before until six hours after the administration every 15 min., and after that, blood samplings were continued until 21 hours every one hour by an intravenous indwelling catheter. Serum FSH, LH, prolactin and testosterone levels were determined by RIA, and the changes of the pulsatile patterns of FSH and LH, and the circadian profile of these hormones by the administration of bromocriptine were analysed. Serum prolactin levels decreased significantly (p less than 0.005) from two hours after the administration of bromocriptine and remained in a very low range until the end of the experiment. The basal levels of FSH showed a significant decrease from two to six hours after the administration (p less than 0.005). Also the basal levels of LH showed a significant decrease from two to six hours after the administration (p less than 0.005). However, the basal levels of serum FSH and LH did not show significant decreases after that until the end of the experiment. No significant change was observed in the amplitude or the frequency of the pulsatile patterns of FSH and LH until six hours after the administration of bromocriptine. The serum levels of testosterone were also significantly decreased from two to six hours after the administration (p less than 0.005), but they did not show a significant decrease after that until the end of the experiment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Vasodilatory and diuretic actions of alpha-human atrial natriuretic polypeptide (alpha-hANP).

Vascular and diuretic actions of synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) were studied using anesthetized dogs and isolated canine arterial strip preparations. alpha-hANP, when given intra-arterially or intravenously, dilated the renal artery more selectively than the vertebral, femoral, common carotid and coronary arteries. alpha-hANP selectively relaxed the high K+-contracted renal artery strip as compared with the basilar, coronary and femoral arterial strips. Intravenous alpha-hANP also increased urine volume and urinary excretion of electrolytes at doses, at which it increased renal blood flow and lowered systemic blood pressure without changing heart rate. It is concluded that alpha-hANP has a vasodilatory property relatively specific for the renal artery, and that it possesses diuretic, natriuretic, kaliuretic, magnesiuretic, calciuretic and chloruretic activities concomitantly with a definite hypotensive activity.

Animals↗

[The mechanism of induction of ovulation by bromocriptine in euprolactinemic anovulation--the role of occult hyperprolactinemia in anovulation].

It has been well documented that ovulation was induced by Bromocriptine treatment in euprolactinemic anovulation. The present study has been carried out to clarify the underlying mechanism. 28 patients with euprolactinemia (PRL less than 25 ng/ml) were treated with a 5 mg daily administration of Bromocriptine. Ovulation was induced in 13 cases, which were determined by their BBT charts. In the ovulated cases, PRL secreting capacities were increased, determined by TRH administration. On the other hand, PRL secreting capacities were normal in the anovulated cases. The studies of the circadian secretion of PRL revealed that a nocturnal hyperprolactinemic state occurred for several hours in the ovulated cases, which was not seen in the anovulated cases. From these results, the mechanism of induction of ovulation by Bromocriptine in euprolactinemic anovulation exists on the suppression of the increased PRL secreting capacity, which may be related to the occulted hyperprolactinemia at night. Ovulated cases by Bromocriptine are seemingly euprolactinemia, but in truth they may be a kind of hyperprolactinemia.

Adult↗

[The effects of bromocriptine on anovulatory patients with high LH and euprolactinemia].

It is well known that an acute administration of Bromocriptine (dopamine agonist) suppresses the serum LH level either in normal women or in women with polycystic ovary syndrome, in whom the serum LH level is elevated. The present study was carried out to examine the effectiveness of Bromocriptine on anovulatory women with a high LH level (serum LH greater than 30 mIU/ml). Bromocriptine was administered for 3 months, 5 mg daily, to 9 anovulatory women with euprolactinemia (serum PRL less than 25 ng/ml). Ovulation was observed by their BBT charts. Before and after the treatment of Bromocriptine, FSH, LH and PRL secreting capacities were tested by LHRH and TRH injection. Also, estrone, estradiol and testosterone levels were measured before and after the Bromocriptine administration. Resting levels of LH, FSH and PRL were 45.4 +/- 11.0 mIU/ml, 11.4 +/- 3.0 mIU/ml, and 14.3 +/- 4.7 ng/ml (M +/- SD), respectively, before the treatment. As a result of the treatment, the LH level was markedly decreased to 27.3 +/- 14.5 (M +/- SD, P less than 0.05), and PRL decreased to 3.76 +/- 4.2 ng/ml (M +/- SD, P less than 0.005). On the other hand, FSH did not show a marked change. The responsiveness of LH to LHRH before the treatment showed a marked increase, which was suppressed by Bromocriptine. However, FSH showed no change. The responsiveness of PRL to TRH was suppressed by Bromocriptine. Serum estrone, estradiol and testosterone levels before the treatment were 115.5 +/- 76.7 pg/ml, 93.7 +/- 61.0 pg/ml and 0.809 +/- 0.209 ng/ml (M +/- SD), respectively, which showed no significant change after the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

New antiarrhythmic agents. N-aryl-8-pyrrolizidinealkanamides.

The synthesis and antiarrhythmic activity of N-aryl-8-pyrrolizidinealkanamides are described. The target compounds were evaluated for their ability to protect against chloroform-induced fibrillation in mice. Many of them were found to have antifibrillatory activity comparable to that of lidocaine; several are more potent than lidocaine. N-(2,6-Dimethylphenyl)-8-pyrrolizidineacetamide which was found to be more potent and less toxic (LD50) than lidocaine, also showed a long duration of action in dogs with ventricular arrhythmias after oral administration.

Animals↗