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N Kitajima

Publications and source records attributed to N Kitajima.

At least 37 records · Page 2Linked to original sources
PubMed1990

Galanin stimulates immunoreactive growth hormone-releasing factor secretion from rat hypothalamic slices perifused in vitro.

The effect of galanin (GAL) on the release of GH-releasing factor (GRF) and somatostatin (SRIF) was examined in an in vitro perifusion system of rat hypothalamic slices. GAL at doses of 10(-7) and 10(-6)M stimulated the release of immunoreactive GRF while it failed to affect SRIF release. Therefore, in vivo stimulation of GH release by GAL may be explained in part by the GRF-releasing effect of this peptide.

Animals↗
PubMed1990

[Treatment of priapism by caverno-spongio-anastomosis].

We experienced two cases of priapism; one, idiopathic and low flow type, the other post-traumatic and high flow type. We tried caverno-spongio-anastomosis (CSA) as an operative treatment in both cases. Postoperative courses were uneventful. We suggest that CSA is a simple and reliable treatment of priapism.

Adult↗
PubMed1989

Insulin-like growth factor I (IGF-I) production and the presence of IGF-I receptors in rat medullary thyroid carcinoma cell line 6-23 (clone 6).

To clarify whether insulin-like growth factor I (IGF-I) is an autocrine growth factor of rat medullary thyroid carcinoma (MTC) cell line, 6-23 (clone 6), IGF-I binding to MTC cell membranes, IGF-I levels in the conditioned culture medium of MTC cells and the effects of IGF-I on methyl-[3H]thymidine incorporation to MTC cells were examined. Scatchard analysis of saturation binding studies revealed the association constant and the maximal binding capacity were 1.0 x 10(9) M-1 and 199 fmol/mg of membrane protein, respectively. The binding of [125I]IGF-I to MTC cell membranes was inhibited by unlabeled IGF-I, IGF-II and insulin; the relative potencies were IGF-I greater than IGF-II much greater than insulin, suggesting the presence of type I IGF receptors in MTC cells. IGF-I levels in the conditioned culture medium of MTC cells were 120 +/- 3 pM (mean + SE). IGF-I (10(-10) to 10(-8) M) dose-dependently stimulated methyl-[3H]thymidine incorporation to MTC cells. These findings suggest a possible role of IGF-I as an autocrine growth factor for MTC cells.

Animals↗
PubMed1989

Physiological role of somatostatin-mediated autofeedback regulation for growth hormone: importance of growth hormone in triggering somatostatin release during a trough period of pulsatile growth hormone release in conscious male rats.

In mammals including human, it is generally accepted that growth hormone (GH) can regulate its own secretion through an autofeedback mechanism in which somatostatin (SRIF) may be involved. To explore a physiological role of SRIF-mediated GH autoregulation, the effect of exogenous human GH administration on plasma rat GH response to [D-Ala2, Nle27]-human GH-releasing hormone-(1-28)-agmatine (hGHRH-analog), which does not crossreact with anti-rat GH-releasing hormone gamma-globulin (GHRH-Ab), was examined in conscious male rats treated with GHRH-Ab in the absence and presence of anti-SRIF gamma-globulin (SRIF-Ab). Enhanced SRIF release during a trough period of natural pulsatile GH secretion, suggested by the blunted GH response to exogenous hGHRH-analog, no longer occurred when major GH secretory bursts were abolished by GHRH-Ab treatment. On the other hand, when hGH was administered in GHRH-Ab-treated rats so as to simulate the quantity and dynamic change of GH in hypophysial portal circulation in rats exhibiting pulsatile GH secretion, hGHRH-analog-induced GH rises were significantly suppressed during the period corresponding to a GH trough. This suppression was completely prevented by simultaneous treatment with SRIF-Ab. Furthermore, administration of bovine GH, but not ovine prolactin, resulted in significant suppression of hGHRH-analog-provoked GH rises. These findings suggest that enhanced SRIF release during a trough period of spontaneous GH secretory rhythm is induced by the preceding GH secretory burst, and also suggest a possible role for SRIF-mediated GH autoregulation in a physiological state.

Agmatine↗
PubMed1989

Orchiopexy for intravaginal testicular torsion. Ring-shaped fixation of the lower part of the testis.

As a surgical therapy for intravaginal testicular torsion, we developed a testicular fixation method considering the testis in intravaginal testicular torsion in comparison with the normal one. With our method, the lower part of the testis is fixed in a ring form around the testicular long axis to show the wide extravaginal area similar to that of a normal testis. We believe that this method is simple, logical and effective to fix the testis in intravaginal testicular torsion.

Humans↗
PubMed1989

Effects of dopamine on immunoreactive growth hormone-releasing factor and somatostatin secretion from rat hypothalamic slices perifused in vitro.

The effects of dopamine (DA) on the release of GRF and somatostatin (SRIF) from the hypothalami of adult male rats were examined in an in vitro perifusion system using horizontal hypothalamic slices, 400 micron thick, including the median eminence and arcuate nuclei. When hypothalamic slices from five animals were perfused in a chamber with artificial cerebrospinal fluid (ACSF) at a flow rate of 100 microliters/min under a gaseous phase of 95% O2 and 5% CO2 at 37 C, rat (r) GRF- and SRIF-like immunoreactivities (-LI) were constantly detected in 30-min perifusates at least until 240 min of perifusion, and during the perifusion with 60 mM K+, the concentrations of rGRF-LI and SRIF-LI were increased 2.1 and 3.2 times, respectively, over basal values. Under the perifusion with ACSF containing normal goat gamma-globulin, the addition of 10(-8) M DA resulted in a significant increase in SRIF-LI from 8.2 +/- 0.3 to 14.3 +/- 1.5 pg/hypothalamus.30 min, but conversely, it caused a slight but significant decrease in rGRF-LI from 4.5 +/- 0.9 to 2.0 +/- 0.3 pg/hypothalamus.30 min. On the other hand, 10(-8) and 10(-6) M DA significantly stimulated rGRF-LI release from hypothalamic slices perifused with ACSF containing anti-SRIF goat gamma-globulin. These findings suggest that DA is a secretagogue for both SRIF and rGRF in the hypothalamus, but the rGRF-stimulating effect of DA is masked unless the action of endogenous SRIF is attenuated.

Animals↗
PubMed1988

Discordance between growth hormone (GH) responses after GH-releasing hormone and insulin hypoglycemia in myotonic dystrophy.

Plasma GH responses to human GHRH, arginine, L-dopa, and insulin-induced hypoglycemia were determined in seven myotonic dystrophy (MD) patients. An iv bolus injection of GHRH-(1-44)-NH2 (1 microgram/kg BW) only slightly increased plasma GH concentrations in MD patients. The mean peak plasma GH level after GHRH injection [4.2 +/- 0.8 (+/- SE) micrograms/L] was significantly lower than that in 10 age-matched normal subjects (26.7 +/- 4.3 micrograms/L) or that in 6 patients with progressive muscular dystrophy (22.8 +/- 6.6 micrograms/L) whose nutritional status was similar to that of the MD patients. Even with a larger dose of GHRH (3 micrograms/kg BW), the plasma GH rises were minimal in the MD patients (mean peak, 5.9 +/- 1.8 micrograms/L). The plasma GH responses to a 30-min iv infusion of arginine (0.5 g/kg BW) and oral ingestion of L-dopa (0.5 g) were attenuated to a similar extent, whereas insulin-induced hypoglycemia caused a significant increase in plasma GH in all seven MD patients [mean peak, 17.4 +/- 4.1 (+/- SE) microgram/L]. The plasma TSH responses to TRH and plasma insulin-like growth factor I levels were similar in the MD patients and normal subjects. These findings suggest that 1) the impaired GH release after GHRH, arginine, and L-dopa administration in MD patients is not due to somatotroph deficiency, since the GH response to hypoglycemia is well preserved; and 2) insulin-induced hypoglycemia may stimulate GH release at least in part via inhibition of somatostatin release.

Adult↗
PubMed1987

The effect of hypothalamic deafferentation on rat growth hormone-releasing factor (rGRF)-like immunoreactivity content in the medial basal hypothalamus of rats.

Rat growth hormone releasing factor (rGRF)- and somatostatin (SRIF)-like immunoreactivities (LI) were determined by radioimmunoassay in the medial basal hypothalamus (MBH) of the rat with either complete deafferentation (CD) or a sham operation. Two weeks after the surgery the mean amount of SRIF-LI in the isolated MBH was about 70% less than that in the sham-operated animals. On the other hand, the mean rGRF-LI in the MBH decreased only approximately 30% as compared to the levels in the sham-operated animals, the difference being statistically insignificant. These findings are consistent with anatomical evidence that the majority of the GRF perikarya are located in the arcuate nucleus, but a few are found outside the MBH, whereas the majority of the SRIF perikarya are located outside the MBH.

Animals↗
PubMed1987

Clinical reports on plasma exchange in the Kidney Center, Tokai University School of Medicine.

There were 72 patients (19 with hepatic failure, 10 with fulminant hepatitis, eight with paraquat poisoning, eight with rheumatoid arthritis, five with myasthenia gravis, four with hyperlipidemia, four with systemic arteriosclerosis including brain infarction, three with pemphigus vulgaris, two with multiple myeloma, two with systemic lupus erythematosus, two cases non-specific Ig-G antibody, two cases medication with an anticancer drug, one with multiple sclerosis, one with Crohn's disease with amyloid kidney and one with chronic myeloblastic leukemia) treated by plasma exchange in the Kidney Center, Tokai University School of Medicine from Jan. 1983 to Dec. 1986. We performed plasma exchange using fresh frozen plasma in 40 cases and Lactate-Ringer's solution containing albumin (4.0-5.0%) in 20 cases as the replacement fluid. In 17 cases, we performed double filtration plasma exchange with the recycle system and no replacement fluid. Although PE therapy did not constitute a basic therapy for hyperlipidemia, pemphigus vulgaris, rheumatoid arthritis, myasthenia gravis, and systemic lupus erythematosus, it was effective in relieving severe clinical symptoms. At the present time, conventional plasma exchange does not improve the survival rate of patients with hepatic failure and fulminant hepatitis. Developments of a new artificial liver support apparatus and identity of many toxic substances in hepatic failure are necessary. No hypotension, hypovolemic shock or other significant complications were experienced.

Adult↗
PubMed1986

[A clinical observation on urogenital tuberculosis].

A clinical observation was made on 30 cases of urogenital tuberculosis diagnosed and treated at the urological department of our Hospital between January, 1976 and December, 1984. Furthermore, 20 of them were examined for drug resistance and investigated for this tendency. They accounted for 0.23% of the outpatients. Male to female ratio was 2 to 1, but on urological tuberculosis this ratio was even. The average age was 43.7 and 50% of the patients who had a history of tuberculosis. Mycobacterium tuberculosis could be detected in 24 of the 30 cases (80%) and 18 of the 21 cases (85.4%) of urological tuberculosis. Drug resistance was examined in 20 patients. The resistant ratio of M. tuberculosis against primary drugs such as SM, PAS, INAH was low and a high resistant ratio was observed on secondary drugs such as EB, RFP, TH. These clinical observations are reported and herein discussed.

Adult↗
PubMed1986

[The efficacy of a tissue adhesive agent (BI 0.022) in urinary tract surgery--application to pyelo- and ureterolithotomy].

To evaluate the effect of a tissue adhesive agent (BI 0.022) on renal pelvic and ureteral surgery, the adhesive was applied for 44 patients with urolithiasis. The conventional suture method was performed in 87 patients as a control. The tissue adhesive is composed of fibrinogen, thrombin, factor XIII, aprotinin and CaCl2. The number of sutures for closure of the incision made on the rental pelvis and the ureter was significantly reduced by the use of the tissue adhesive (p less than 0.01). There was no tendency of increase in urinary leakage following the application of the method in comparison with the control. Furthermore, it was noteworthy that 10 in cases with less than a 1 cm ureteral incision were completely closed by the use of the adhesive agent. This tissue adhesive agent should be valuable for renal pelvic and ureteral surgery as a simple substitute for the conventional suture method.

Adult↗
PubMed1986

A clinical trial of removal of bilirubin in blood by Evaflux-2A.

We performed both free and albumin-bound bilirubin removal therapy using the Evaflux-2A and evaluated its clinical effects. The removal rates of total bilirubin in the first and second sessions were 31.4%, and 31.0%, respectively. Our clinical data suggested that plasma exchange using Evaflux-2A and an albumin-added electrolyte solution as the substitute fluid was useful in the treatment of hyperbilirubinemia.

Bilirubin↗