Effects of selective vagotomy on circadian rhythms of plasma glucose, insulin and food intake in control and ventromedial hypothalamic (VMH) lesioned rats

Effects of hepatic and celiac vagotomy on circadian rhythms of plasma glucose, insulin, and food intake were examined in sham-operated (control) and ventromedial hypothalamic (VMH) lesioned rats. Rats were acclimated to the condition with a 12-hour light-dark cycle for 1 week before surgery. One week after VMH lesions, control and VMH lesioned rats were divided into three groups: sham vagotomy, hepatic vagotomy, and celiac vagotomy. Three days after vagotomy, food intake was measured at 6-hour intervals. Seven days after vagotomy, plasma glucose and insulin were measured at the midpoint of each feeding period. In control rats, hepatic vagotomy destroyed circadian rhythms of plasma glucose and insulin probably due to removal of afferent function. In VMH lesioned rats, celiac vagotomy destroyed circadian rhythm of food intake due to the reduction of plasma insulin by removal of efferent function without affecting the loss of circadian rhythms of plasma glucose and insulin.

Effects of MCI-225 on memory and glucose utilization in basal forebrain-lesioned rats

The effects of MCI-225 on amnesia, the cerebral glucose metabolism, and choline acetyltransferase (ChAT) activity in basal forebrain (BF)-lesioned rats were studied in comparison with those of tacrine. Bilateral BF lesions with ibotenic acid impaired the performance in passive avoidance (PA) tasks. Single administration of MCI-225 (10 mg/kg, PO) after a 2-week postoperative recovery period, increased the escape latencies in the PA task, but was not statistically significant. Repeated administration of MCI-225 (0.3 and 1 mg/kg, PO for 6 days) significantly reversed the PA failure. The BF-lesioned rat exhibited a marked decrease in the local cerebral glucose utilization (LCGU) in the frontal cortex, parietal cortex, and caudate-putamen. MCI-225 (1 mg/kg, PO for 5 days) significantly ameliorated the reduction of the LCGU in the parietal cortex. MCI-225 did not change the decrease in the cortical ChAT activity induced by the BF lesion. Repeated administration of tacrine reversed the PA failure (0.3 mg/kg, PO) but failed to prevent the decrement in the LCGU and the ChAT activity. These results suggest that MCI-225 could be effective in the treatment of senile dementia of the Alzheimer type, which is accompanied with both deficit in the BF-cortex cholinergic neuron and cerebral glucose hypometabolism.

Peripheral 3-hydroxybutyrate and food intake in a model of dietary-fat induced obesity: effect of vagotomy

We have examined the effect of peripheral 3-hydroxybutyrate injections on food intake and the contribution of the vagus nerve in the resistance to dietary fat-induced obesity in a rodent model. S 5B/Pl rats, which are resistant to dietary-fat induced obesity, and Osborne-Mendel rats, which are sensitive, were adapted to reverse light cycle. Food intake was measured for 24 h following the injection of 3-hydroxybutyrate, lactate, or glycerol (all 5 mMol/kg0.75, SC) at the onset of dark. Three-hydroxybutyrate reduced food intake (p < 0.0001) in S 5B/Pl rats only. Lactate reduced food intake slightly (p < 0.009) in both strains and glycerol had no effect on food intake. In a second experiment, S 5B/Pl and Osborne-Mendel rats were adapted to a high-fat diet and were then subjected to either selective hepatic vagotomy or sham operation. Vagotomy had no effect on weight gain of Osborne-Mendel rats but allowed weight gain in S 5B/Pl rats (p < 0.0001). Even in vagotomized S 5B/Pl rats, however, blood 3-hydroxybutyrate levels were inversely associated (r = -0.50) with food intake. These data suggest that the hepatic vagus nerve may contribute to the resistance of S 5B/Pl rats to dietary-fat induced obesity, but the data do not rule out a strictly central role for the regulation of food intake by 3-hydroxybutyrate in this strain.

[Olfactory disturbance caused by chronic sinusitis]

Sinusitis has been reported to be one of the major causative etiologies of olfactory disorder. According to our data during last 3 years, 47.5% of all cases of olfactory disorder were attributed to sinusitis. Persistent olfactory disturbance was often critical even after resection of the pathological sinus mucosa by surgery for chronic sinusitis. Accordingly, olfactory epithelial inflammation involved in sinusitis may be considered another important causative factor disturbing the restoration of olfactory acuity. To elucidate this hypothesis, the following experimental and clinical studies were carried out. (1) A morphological study was done with specimens taken from the olfactory cleft of rabbits with experimentally induced sinusitis to analyze the inflammatory effects, and the degree of inflammatory damage was compared, histopathologically between olfactory and respiratory epithelium. SEM observation in the morphological study showed delayed healing in the olfactory portion in comparison with the respiratory portion (p < 0.01). Cell proliferation activity as determined by immunohistochemical study with bromodeoxyuridine (BrdU) was significantly greater in the respiratory area of the cases with sinusitis than in the control (p < 0.01). Cell proliferation status may play a significant role in this delay. (2) Olfaction tests were performed in patients with sinusitis accompanied with olfactory disturbance. In addition to both T&T olfactometry and intravenous olfactometry using fursultiamine (Alinamin Test), Smell Identification Test (SIT) and Threshold Test by graded Phenyl Ethyl Alchol (PEA) were applied to estimate the olfactory acuity of the patients with sinusitis. The results of SIT and PEA tended to parallel not the Alinamin Test but T&T olfactometry. Results showed that the olfactory disorder caused by sinusitis tended to be severe. The results showed that the epithelial factor is important in explaining olfactory disorder etiologically in cases of sinusitis. In particular, olfactory disturbance tended to persist.

Expression of the human interleukin 6 receptor alpha-chain in Xenopus laevis oocytes

We investigated the biochemical properties of the 80 kDa binding subunit (gp80) of the human interleukin 6 receptor (IL-6R) in the genetic environment of the amphibian Xenopus laevis. In vitro transcribed mRNA encoding full length human gp80 was microinjected into Xenopus laevis stage VI oocytes. Protein expression was monitored by iodinated IL-6 and human gp80-specific monoclonal antibodies (mAb) PM1 and MT18. Maximal IL-6 binding activity was observed between 36-42 h after injection. Scatchard analysis indicated that gp80-injected oocytes expressed two independent classes of IL-6 binding sites of high- (Kd1 = 9 x 10(-11) M, 20 x 10(6) sites/cell) and low-affinity (Kd2 = 2 x 10(-9) M, 70.3 x 10(6) sites/cell). PM1 but not MT18 completely inhibited IL-6 binding to injected eggs. Our data suggest that the human IL-6R alpha-subunit gp80 is sufficient to confer high- and low-affinity IL-6 binding to Xenopus laevis oocytes.

Disruption by interferon-alpha of an autocrine interleukin-6 growth loop in IL-6-dependent U266 myeloma cells by homologous and heterologous down-regulation of the IL-6 receptor alpha- and beta-chains

IL-6 is an autocrine growth factor for U266 myeloma cells and their growth is inhibited by IFN-alpha or IL-6 mAb. We asked, therefore, whether IFN-alpha-induced growth inhibition involved IL-6. IFN-alpha and mAb against IL-6, the IL-6R alpha-(gp80) or beta-chain (gp130) potently inhibited U266 cells. Remarkably, this effect occurred despite IFN-alpha-augmented secretion of endogenous IL-6. However, examining the IL-6R revealed that IFN-alpha drastically curtailed expression of the IL-6R alpha- and beta-chain. This effect occurred on two different levels (protein and mRNA) and by two different mechanisms (directly and indirectly through IL-6). First, IFN-alpha, but not IL-6, greatly decreased gp80 and, to a lesser extent, gp130 mRNA levels which resulted in a loss of IL-6 binding sites. Second, IFN-alpha-induced IL-6 predominantly down-regulated membrane-bound gp130. IFN-alpha-mediated decrease of gp80 levels was not detected on IL-6-independent myeloma (RPMI 8226) or myeloid cells (U937). We conclude that IFN-alpha inhibited IL-6-dependent myeloma cell growth by depriving U266 cells of an essential component of their autocrine growth loop, a functional IL-6R.

Effects of an antistroke agent MCl-186 on cerebral arachidonate cascade

Activation of the cerebral arachidonate (AA) cascade is one of the major causes of edema and tissue injury in cerebral ischemia, particularly after reperfusion. The cascade produces toxic oxygen radicals responsible for peroxidative neurodegeneration and synthesizes, the potent edematous inducer, leukotrienes. The present study was undertaken to evaluate the effect of MCl-186 (3-methyl-1-phenyl-pyrazolin-5-one), a radical scavenger and antioxidant which has beneficial anti-ischemic actions, on the cerebral AA cascade. Postischemic treatment with MCl-186 (1.0 and 3.0 mg/kg i.v.) significantly inhibited the aggravation of cortical edema seen 60 min after recirculation following 30 min of ischemia in gerbils. An antilipoxygenase agent, FPL-55712 (7-[3-(4-acetyl-3-hydroxy-2-propylphenoxy)-2- hydroxypropoxy]-4-oxo-8-propyl-4H-1-benzopyran-2-carboxylic acid, monosodium salt; 10 mg/kg i.v.) or AA-861 ((2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinon e; 60 mg/kg i.p.) was also effective in this model; however, indomethacin (4 mg/kg i.p.), a cyclooxygenase inhibitor, was ineffective. Concomitant treatment with MCl-186 (0.1-3.0 mg/kg i.v.) remarkably inhibited the swelling observed 24 hr after cortical infusion of AA (80 micrograms) in rats. Similarly, antilipoxygenase agents clearly inhibited the AA-induced edema. Furthermore, postischemic treatment with MCl-186 (0.3-3.0 mg/kg i.v.) inhibited the facilitation of cerebral leukotriene synthesis seen 15 min after recirculation following 30 min of ischemia in gerbils. These findings suggest that the site of action of MCl-186 as an anti-ischemic agent may be closely associated with the cerebral AA cascade, especially the lipoxygenase system, activated by ischemia-reperfusion.

Etretinate-induced heterotopic bone formation about the hip joint. A case report including ultrastructural study

Despite considerable documentation for retinoid-induced hyperostosis, sufficient knowledge regarding its management and histologic features is not available. In a 26-year-old man with etretinate-induced heterotopic bone formation about the hip joint, the use of etidronate disodium was unsuccessful. Surgical excision of the heterotopic bone dramatically improved restricted motion of the hip joint without initiating significant postoperative heterotopic ossification. Ultrastructural study showed abundant myofibroblasts in the fibrous tissue close to the heterotopic bone. Their role in local biologic events should be determined.

Effects of intraventricular administration of neuropeptide Y on feeding behavior in fasted female rats with ventromedial hypothalamic lesions

The role of ventromedial hypothalamic nucleus (VMN) in feeding behavior induced by central administration of porcine neuropeptide Y (NPY) in fasted female rats was investigated focusing on the effect of the intracerebroventricular (i.c.v.) injection of NPY on food intake in rats with VMN lesions after 24 h of food deprivation. Cumulative food intake was measured 1, 3 and 6 h after injection. In Exp. 1, the i.c.v. injection of NPY into intact rats stimulated food intake compared with the injection of saline 1 and 3 h after the injections in a dose dependent manner (1 h; NPY 1 microgram, 3.29 +/- 0.43, 2 micrograms, 4.64 +/- 0.88, 5 micrograms, 5.15 +/- 0.61 vs. saline 2.48 +/- 0.42 g, P < 0.05 in 2 and 5 micrograms). 5 micrograms of NPY significantly stimulated food intake 6 h later. In Exp. 2, i.c.v. injection of NPY (2 micrograms) in VMN-lesioned rats showed no significant effect on food intake compared with the injection of saline 3 weeks after VMN lesioning (1 h; NPY 2 micrograms, 2.46 +/- 0.58 vs. saline 2.39 +/- 0.12 g). These results suggest that central administration of NPY enhances food intake in fasted female rats and that the VMN is one of the crucial sites of NPY induced feeding.

Primary adenocarcinoma of the vermiform appendix associated with transitional cell carcinoma of the bladder

A case of primary adenocarcinoma of the vermiform appendix coexisting with transitional cell carcinoma (TCC) of the bladder is presented. The patient was a 74-year-old male who underwent radical cystectomy with continent urinary diversion using the Florida pouch. Two different cancers were found, TCC of the bladder and mucinous adenocarcinoma of the appendix. To our knowledge, this is the only such case reported in the medical literature.

Effects of a novel compound MCI-225 on impaired learning and memory in rats

Effects of MCI-225, [4-(2-fluorophenyl)-6-methyl-2-(1-piperazinyl)thieno[2,3-d]pyrimidine monohydrate hydrochloride] on experimental amnesia were studied in rats and compared with those of THA [9-amino-1,2,3,4-tetrahydroacridine]. In the Morris-type water maze task, MCI-225 (1-10 mg/kg, PO) reduced the spatial learning impairment induced by scopolamine (0.5 mg/kg, IP). In a passive avoidance (PA) task, administration of MCI-225 prior to training (1-30 mg/kg, PO) lessened the carbon dioxide (CO2)-induced amnesia in a dose-dependent manner. MCI-225 (1-100 mg/kg) did not affect gross behavior. THA (0.1-3 mg/kg, PO) reduced scopolamine-induced learning deficits in the water maze task, but the effect was not significant. THA (0.3-3 mg/kg, PO) also ameliorated the CO2-induced amnesia, although slightly, in the PA task. THA (10 mg/kg, PO) increased locomotor activity and higher dose of THA (30 mg/kg, PO) induced tremor, hypersalivation, and muscle relaxation. These results suggest that MCI-225 lessens impairments in learning and memory without causing serious behavioral abnormalities.

Protective effects of MCI-186 on cerebral ischemia: possible involvement of free radical scavenging and antioxidant actions

The anti-ischemic effects and a possible mechanism of a new antistroke agent, 3-methyl-1-phenyl-pyrazolin-5-one (MCI-186), were studied. Preischemic treatment with MCI-186 (3 mg/kg i.v.) facilitated the recovery of electrocorticographic activity and prolonged survival time in global complete ischemia of rats; MCI-186 (1 and 3 mg/kg i.v.) also mitigated dysfunction of the blood-brain barrier and energy failure in hemispheric embolization of rats. Postischemic treatment with MCI-186 (3 mg/kg i.v.) decreased cortical infarction in focal embolization of rats. MCI-186 (0.6-2.4 mM) inhibited the OH.-induced hydroxylation of salicylate (maximal inhibition, 40.2%), but at 100 microM it did not influence O2- generation. MCI-186 inhibited the formation of linoleic acid-conjugated dienes caused by OH. (IC50 = 32.0 microM). Also, concurrent administration of MCI-186 (3-100 mg/kg i.v.) ameliorated hyperglycemia, hyperlipopeoxidemia and degranulation of beta-cells in alloxan (40 mg/kg i.v.)-treated rats. In addition, MCI-186 inhibited iron-dependent peroxidation in rat brain homogenates and mitochondrial homogenates (IC50 = 15.0 and 2.3 microM, respectively) and prevented iron-dependent peroxidative disintegration of mitochondrial membranes (IC50 = 39.0 microM). These findings suggest that MCI-186 has potent anti-ischemic actions and that its mechanism may be closely associated with beneficial antioxidant activities.

Gastric damage and body weight loss in LHA-lesioned rats: effects of cytoprotective geranylgeranylacetone

We investigated the development of gastric damage and body weight (BW) loss in lateral hypothalamic area (LHA)-lesioned rats, measured 2 h and 1 and 3 days after the lesioning (experiment 1), as well as the effects of geranylgeranylacetone (GGA), a cytoprotective antiulcer agent, on these disorders (experiment 2). In experiment 1, BW of LHA-lesioned rats decreased throughout the 3-day experiment. In LHA-lesioned rats, gastric mucosal lesions appeared 1 day after lesioning in the glandular portion and persisted, whereas those in the rumenal portion appeared only after 3 days. Gastric transepithelial potential differences (PDs) of glandular portion began to decrease after 2 h and had decreased in both portions. Gastric acid output was increased transiently at 2 h but it was not high after 1 day and after 3 days was lower than that in sham-LHA-lesioned rats. In experiment 2, PDs of the rumenal decreased more in LHA-lesioned rats than in sham-LHA-lesioned rats pair fed to LHA-lesioned rats after 3 days. Three days of treatment with GGA (200 mg/kg ip) improved PDs of rumenal and glandular portions in LHA-lesioned rats and reduced lesions of the rumenal portion. Loss of BW in LHA-lesioned rats was significantly but not completely inhibited by GGA. These results indicate that disturbance to the gastric defensive mechanism plays an important role in the development of gastric lesions after LHA lesions and that the impairment of gastric functions may be a partial cause of the loss of BW in LHA-lesioned rats.

A case of inverted papilloma of the ureter: is the DNA ploidy pattern associated with occurrence of transitional cell carcinoma of the bladder?

We describe herein a case of inverted papilloma of the ureter, in which transitional cell carcinoma of the bladder developed twenty-three months after nephroureterectomy. Flow cytometric analysis of formalin-fixed and paraffin-embedded archival material of the inverted papilloma revealed DNA aneuploidy pattern and relatively high percentage of S phase. Retrospectively, DNA measurement thus provided the predictive value regarding biological activity and the clinical behaviour of the present case.

Glucagon injected in the lateral hypothalamus stimulates sympathetic activity and suppresses monoamine metabolism

Glucagon injected in the lateral hypothalamus stimulates sympathetic activity and suppresses monamine metabolism. The central hypothesis underlying this study is that there is a reciprocal relationship between food intake and sympathetic activity to IBAT. This hypothesis was tested by using intrahypothalamic microinjections of glucagon, a peptide that has been reported to decrease food intake. Sympathetic nerve activity to interscapular brown adipose tissue (IBAT) was measured as electrophysiological discharges of sympathetic nerves to IBAT. The microinjection of glucagon into the lateral hypothalamus (LH) increased sympathetic nerve activity by +103.8 +/- 35.0% (mean +/- S.E.M.) from pre-injection basal level by 30 min after injection. There was a gradual return to baseline. Micro-injection of glucagon into the LH depressed food intake. Monoamine metabolism was measured by using a microdialysis probe attached to a guide cannula for microinjection of glucagon into the LH. After microinjection of glucagon, the dialysates were collected over 30 min intervals and assayed for norepinephrine (NE), serotonin (5-HT), dopamine (DA) and their metabolites (3-methoxy-4-hydroxyphenylglycol (MHPG); 5-hydroxyindole-3-acetic acid (5-HIAA); and 3,4-dihydroxyphenylacetic acid (DOPAC). Glucagon suppressed both NE and MHPG concentrations in the lateral hypothalamus (LH), and the concentration of DOPAC was also decreased. There was no change of 5-HT concentration but 5-HIAA levels were reduced by glucagon treatment. These data show that glucagon injected in the LH stimulates sympathetic activity and suggest that this may have occurred by suppression of norepinephrine, dopamine and serotonin turnover in the LH of freely moving rats. These data support the hypothesis of a reciprocal relationship between food intake and sympathetic activity.

Osteosarcoma of the talus. A case report

A 20-year-old man complained of increasing pain and swelling in the right ankle joint. Radiographs of the ankle demonstrated an ill-defined osteolytic lesion in the talus associated with a small, round bone formation just proximal to the neck of that bone. Histologic examination of the lesion showed osteoblastic osteosarcoma originating in the talus. Below-knee amputation was performed because of the peripheral location of the tumor and the close anatomic confines of the foot. A literature review demonstrated that the calcaneus and metatarsals are favorite sites of this tumor in the foot, with only one case in the talus. A second case of osteosarcoma in the talus seems to have not been previously reported.

Effects of GABA and L-glutamate on the gastric acid secretion and gastric defensive mechanisms in rat lateral hypothalamus

The effects of administration of an inhibitory GABAergic or excitatory glutaminergic neurotransmitter into the lateral hypothalamic area (LHA) on gastric acids, an aggressive mechanism, and transepithelial potential difference (PD) and mucosal blood flow (MBF), defensive mechanisms, were examined in anesthetized rats, since lesions of LHA in these animals cause gastric mucosal damage and electrical stimulation stimulates gastric acids and antral contractions. Microinfusion of the inhibitory neurotransmitter, muscimol (GABA agonist) resulted in an increase in gastric acid secretion and in PD and MBF. The GABA antagonists picrotoxin and bicuculline methiodide, in contrast, decreased these three factors. The excitatory neurotransmitter L-glutamate induced only an increase of MBF. Thus, the GABAergic system in LHA stimulates the gastric functions, both defensive and aggressive mechanisms, while the glutaminergic system increases only a portion of the defensive system. The results suggest that there is a significant interaction between LHA and stomach functions.

Impaired growth hormone secretion in VMH lesioned rats

To investigate impaired growth hormone (GH) secretion in ventromedial nuclei (VMH) lesioned rats, we examined spontaneous plasma GH secretion, and plasma GH responses to arginine, clonidine and growth hormone releasing factor (GRF) under unanaesthetized and unrestrained conditions. Spontaneous GH secretion was blunted with 75% decrease of peak value in VMH lesioned rats, while it clearly existed in control rats. When rats were pre-treated with chlorpromazine (1-2 mg/kg, i.v.) which eliminates pulsatile GH secretion, no difference was observed in the plasma GH response to arginine (1 g/kg, i.v.) or to clonidine (100 micrograms/kg, i.v.) between VMH lesioned and control rats, but response to GRF (10 micrograms/kg, i.v.) was enhanced in the former animals. Administration of antiserum against somatostatin (1 ml) plus chlorpromazine significantly elevated the basal plasma GH level and GH response to arginine in control rats, but did not elevate them in VMH lesioned rats. These results suggest that reduction of both hypothalamic GRF and somatostatin release contribute to the impaired GH secretion in VMH lesioned rats. Reduction of somatostatin caused enhanced GH response to GRF and no increase in basal GH level with pre-treatment of antiserum against somatostatin. Reduction of GRF resulted in a failure to restore GH response to arginine with pre-treatment of antiserum against somatostatin. Reduction of both GRF and somatostatin caused blunted spontaneous GH secretion and normal GH response to arginine and clonidine.

Comparative study of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and tritiated thymidine in a chemosensitivity test using collagen gel matrix

An organ culture system using collagen gel matrix (CGM) was modified and established successfully as a rapid and convenient method for determination of anti-cancer drug sensitivities. The cell viability of a tumor fragment was measured by the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to a colored formazan product, which allowed for quantitative and simple analysis. The sensitivities of KK-47 bladder tumor from nude mice to various anti-cancer drugs tested corresponded closely to those determined in the original CGM assay system using tritiated thymidine, which has a high clinical correlation. Our modified method can be used as a practical and highly reproducible chemosensitivity test in vitro.

Sympathetic nerve activity after discrete hypothalamic injections of L-glutamate

In these experiments L-glutamate, an amino acid which stimulates neuronal discharge, was microinjected into several hypothalamic nuclei and the resultant changes in electrical firing rate of sympathetic nerves innervating interscapular brown adipose tissue (IBAT) were measured. Three patterns of response were seen. A single large stimulatory response was seen when L-glutamate was microinjected into the ventromedial hypothalamus (VMH). Microinjection of L-glutamate into the paraventricular nucleus (PVN) produced a predominantly stimulatory response which was of smaller magnitude than the VMN. However in three animals L-glutamate in the PVN decreased firing rate and in one animal a biphasic response was observed. The second pattern was a decrease in sympathetic activity to IBAT which was the predominant pattern following injection of L-glutamate into the dorsomedial hypothalamus (DMH). However, a biphasic pattern was also observed. Injection of L-glutamate into the lateral hypothalamic area (LHA) produced 3 patterns of response; an increase, a decrease; or a biphasic response in nearly equal numbers of animals. The predominant response to L-glutamate in the preoptic area (POA) was biphasic. These data are consistent with the hypothesis that the VMH is the predominant stimulatory site for activation of the sympathetic nervous system to IBAT in the rat. The DMH and LHA appear to be the predominant inhibitory areas.

Acute and chronic effects of VMH lesions on circadian rhythms in food intake and metabolites

In the dynamic phase, 3 weeks after surgery, food intake increased especially during the latter part of the light cycle in VMH-lesioned rats, and the difference between light and dark cycles disappeared. The rhythms of serum insulin, glucose, and triglyceride disappeared. Concentrations of glucose during the light cycle were lower than those of sham-operated rats, although concentrations of triglyceride and insulin were higher than those of sham-operated rats at all times. In the static phase, 12 weeks after surgery, the difference of food intake between light and dark cycle appeared in VMH-lesioned rats, but the loss of rhythmicity for serum glucose, insulin, and triglyceride remained. Concentrations of glucose except early light phase and concentrations of triglyceride and insulin at all times were higher than those of sham-operated rats. VMH lesions thus abolished circadian rhythmicity in serum insulin, glucose, and triglyceride for a long period; however, the disturbed rhythmicity of food intake was reversible.

In vitro chemosensitivity test for human genitourinary tumors using collagen gel matrix

An in vitro chemosensitivity test using collagen gel matrix assay with quantitative evaluation of cell viability using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide was applied to 40 human genitourinary tumor specimens. Chemosensitivity was determined in 34 (85%) of the 40 specimens. The anticancer drugs tested against 14 renal cell carcinomas showed lower activities than against 15 transitional cell carcinomas with different sensitivity patterns among the individual specimens demonstrated. Our assay system could be successfully applied to human genitourinary tumors and can be used as a practical and highly reproducible chemosensitivity test in vitro.

Effect of beta-endorphin on sympathetic nerve activity to interscapular brown adipose tissue

beta-Endorphin was injected into the third cerebroventricle to investigate its effects on sympathetic nerve activity to interscapular brown adipose tissue (IBAT) in rats. Multiunit discharges of sympathetic nerves to IBAT were recorded electrophysiologically in anesthetized rats. The intracerebroventricular injection of beta-endorphin (125, 250, and 500 pmol/rat in 10 microliters) suppressed sympathetic nerve activity in a dose-related fashion (-23.9 +/- 20.4, -38.7 +/- 7.1, and -66.7 +/- 7.6% 30 min after injection) compared with preinjection baseline. N-acetyl-beta-endorphin (250 pmol) had no effect on sympathetic nerve activity to IBAT. The intraperitoneal injection of naloxone (5.0 mg/rat) did not affect sympathetic nerve activity, but preinjection of naloxone inhibited the suppressive effect of intracerebroventricular injection of beta-endorphin (250 pmol). We conclude that the intracerebroventricular administration of beta-endorphin suppressed the sympathetic nerve activity to IBAT through opioid receptors. The results of this experiment are consistent with the hypothesis that beta-endorphin has a reciprocal effect on food intake and the sympathetic nervous system.

Thermal laser-assisted angioplasty of renal artery stenosis for renovascular hypertension

Percutaneous transluminal laser-assisted angioplasty of a renal artery stenosis was performed in a 16-year-old woman with renovascular hypertension. The stenotic portion of the renal artery was predilated by delivering Nd-YAG laser energy to the terminal tip of a laser catheter. Although the luminal diameter did not increase sufficiently with laser angioplasty alone, it allowed passage of the balloon catheter and subsequent successful balloon angioplasty. Immediately after dilatation, the patient's blood pressure fell to normal, and plasma renin activity decreased. There were no serious complications. Thermal laser angioplasty seems to be an effective adjunct technique for the treatment of severe renal artery stenosis which does not allow initial passage of a balloon catheter.

Effects of cholecystokinin on sympathetic activity to interscapular brown adipose tissue

The effects of injecting cholecystokinin (CCK) into the third ventricle or into selected hypothalamic sites on electrical firing rate of sympathetic nerves to interscapular brown fat (IBAT) has been investigated in anesthetized rats. The hypothesis for these experiments was that there was a reciprocal relationship between sympathetic activity and food intake. Since CCK reduces food intake we predicted that CCK would stimulate sympathetic activity to IBAT. Following the injection of CCK into the third ventricle there was an increase in firing rate of sympathetic nerves to IBAT. When the peptide was injected into either the ventromedial hypothalamic nucleus (VMH) or lateral hypothalamic area (LHA), there was likewise an increase in sympathetic firing rate. The injection of CCK into the paraventricular nucleus produced a small decrease in sympathetic firing rate. In contrast, no effect was seen following injection of CCK into the preoptic area or dorsomedial hypothalamic nucleus. Thus, the VMH or LHA appear to be the principal hypothalamic areas mediating the stimulation of sympathetic activity to IBAT which is observed following the third ventricular injection of CCK. These studies support the hypothesis of a reciprocal relationship between the effects of CCK on the thermogenic component of the sympathetic nervous system and food intake and identify the VMH and LHA as the primary sites for this effect.