The effect of caloric deprivation to stimulate hypothalamic neuropeptide Y (NPY) gene expression is hypothesized to represent a physiologically important adaptation in body weight homeostasis. To evaluate the specificity of this response, we used in situ hybridization histochemistry to measure hypothalamic expression of mRNA encoding NPY, galanin, and the two isoforms of glutamic acid decarboxylase (GAD67 and GAD65) in male Wistar rats either fed ad lib or deprived of food for 24 or 48 h. As expected, food deprivation for 24 and 48 h increased preproNPY mRNA levels in the arcuate nucleus by 43 +/- 13% (p = NS) and 127 +/- 29% (p < 0.
View Article and Find Full Text PDFNeuropeptide Y (NPY) and NPY mRNA are increased in the hypothalamic arcuate nucleus of rats after prolonged fasting but it is not known if NPY mRNA is also affected by more moderate fasting. NPY mRNA was quantified by in situ hybridization at five levels through the rostral/caudal axis of the arcuate nucleus and was found to be expressed in a markedly heterogenous fashion. NPY mRNA increased significantly in the mid portion of the arcuate nucleus after 24 h of fasting and further increased with fasting for 48 and 96 h.
View Article and Find Full Text PDFInsulin acts in the brain to suppress feeding, whereas neuropeptide Y (NPY) has the opposite effect. Since fasting lowers plasma insulin levels and increases hypothalamic synthesis of NPY, we proposed that insulin may inhibit hypothalamic NPY gene expression. To test this hypothesis, we used RIA and in situ hybridization histochemistry to determine if centrally administered insulin could reduce levels of both NPY and its messenger RNA (mRNA) in discreet hypothalamic regions during fasting.
View Article and Find Full Text PDFThe anatomic distribution of high- and low-affinity cardiac glycoside binding sites in the nervous system is largely unknown. In the present study the regional distribution and properties of these sites were determined in rat brain by quantitative autoradiography (QAR). Two populations of cardiac glycoside binding sites were demonstrated with [3H]-ouabain, a specific inhibitor of Na,K-ATPases: (a) high-affinity binding sites with Kd values of 22-69 nM, which were blocked by erythrosin B, and (b) low-affinity binding sites with Kd values of 727-1482 nM.
View Article and Find Full Text PDFThe effects of temperature, halothane concentration, and arterial partial pressure of CO2 on corticomotor evoked potentials (CMEPs) and somatosensory evoked potentials (SSEPs) were studied. Hypothermia causes an increase in CMEP and SSEP latencies. Corticomotor evoked potential amplitude increases with hypothermia to reach a maximum at or below 28 degrees C.
View Article and Find Full Text PDFThe 1-year follow-up data of a multicenter randomized controlled trial of methylprednisolone (30 mg/kg bolus and 5.4 mg/kg/hr for 23 hours) or naloxone (5.4 mg/kg bolus and 4.
View Article and Find Full Text PDFAlthough there is an increase in attention being paid to race and sex variations in crime and delinquency, little has been done to disaggregate the "gender-ratio" problem in order to account for participation in particular offenses, specifically different types of violent crime. Virtually all of the research pertaining to the interaction of gender, race and -violent crime focuses on murder and dichotomizes race into white and black, or white and nonwhite. This paper uses New York City arrest data to examine the extent of violence within various race-sex-crime subgroups.
View Article and Find Full Text PDFInhibition of prostaglandin pathways and calcium channel conduction has been shown to improve neurological outcome after spinal cord injury. Functional recovery from such intervention has been routinely evaluated by a simple motor examination or somatosensory evoked potentials (SSEPs) after short-term drug administration. We comprehensively evaluated the influence of continuously administered indomethacin and nifedipine on functional outcome after impact spinal cord injury.
View Article and Find Full Text PDFIn order to design an approach for localizing IGF-I receptors within the intact CNS, the effect of paraformaldehyde (PAF) fixation on receptor binding was examined. Cryostat sections of rat brains, which were perfused with 0 to 10% PAF, were incubated in 125I-IGF-I and assayed for binding under equilibrium conditions. Binding was quantified from 10 brain regions, involving laminae and nuclei from median eminence, thalamus, hippocampus, choroid plexus, pyriform cortex, and cerebral cortex, by computer densitometry of film autoradiographs.
View Article and Find Full Text PDFDaily injections of high dose human recombinant interleukin-1 beta (IL-1 beta) accelerated the onset of both insulin-dependent diabetes mellitus and lymphocytic thyroiditis in genetically prone BB rats. In diabetes-resistant BB rats, high dose IL-1 beta failed to induce diabetes. Additionally, the presence of neutralizing IL-1 beta antibodies in these rats strongly correlated with inhibition of lymphocytic thyroiditis.
View Article and Find Full Text PDFUsing multiple 35S-labeled oligonucleotide probes concurrently, the type I insulin-like growth factor receptor (IGF-I-R) mRNA was demonstrated by Northern blot hybridization in newborn and adult rat brain as a single species of approximately 11 kilobases. The probes were used to localize IGF-I-R mRNA by in situ hybridization in slices of adult rat brain. The highest levels of IGF-I-R mRNA expression were found in the glomerular and mitral cell body layers of the olfactory bulb, the granule cell body layers of the dentate gyrus and cerebellum, the pyramidal cell body layers of the piriform cortex and Ammon's horn, and the choroid plexus.
View Article and Find Full Text PDFAlthough critics have argued that psychiatric medications in correctional settings are often prescribed in a clinically irrational manner, without adequate diagnostic criteria, and for the purposes of coercive control rather than treatment, there has been no systematic research in an attempt to validate these claims. The present study examines the influence of inmate clinical and social characteristics, as well as prison setting factors, on the prescription of psychiatric medication to New York State prison inmates. Study findings show that clinical characteristics predominate in the psychiatric medication prescription process.
View Article and Find Full Text PDFBy acting in the brain, insulin suppresses food intake, whereas neuropeptide Y (NPY) has the opposite effect. Since fasting increases NPY gene expression in the hypothalamic arcuate nucleus (ARC) and also lowers circulating insulin levels, we hypothesized that the anorexiant effect of insulin could result from insulin inhibition of NPY gene transcription in the ARC. Therefore, we determined whether the administration of insulin (200 mU per 12 hrs) into the 3rd cerebral ventricle of lean (Fa/Fa) female Zucker rats (n = 5) during 48 hrs of food deprivation reduces the expression of preproNPY mRNA in the ARC compared to vehicle-treated controls (n = 5).
View Article and Find Full Text PDFThe BB rat spontaneously develops insulin-dependent diabetes mellitus (IDDM) in association with marked insulitis in the islet of Langerhans. Since platelet-activating factor (PAF-acether) is involved in allergic and inflammatory reactions, we tested a PAF antagonist, Ginkgolide B (BN 52021) for potential effects on islet inflammation and diabetes. Diabetes prone BB/Wor rats were treated daily from weaning at 25 days until 105 days of age with either saline (n = 30, controls), 10 (n = 25, low dose) or 20 (n = 30, high dose) mg/kg body weight of BN 52021.
View Article and Find Full Text PDFEndocrinology
December 1990
Insulin receptor mRNA was demonstrated in rat brain slices by in situ hybridization with three 35S-oligonucleotide probes and contact film autoradiography. Specificity was confirmed by showing that (a) excess unlabeled probe abolished the signal, (b) an oligonucleotide probe for rat neuropeptide Y mRNA showed a different distribution of hybridization signal, and (c) the distribution of insulin receptor binding was consistent with the distribution of insulin receptor mRNA. Insulin receptor mRNA was most abundant in the granule cell layers of the olfactory bulb, cerebellum and dentate gyrus, in the pyramidal cell body layers of the pyriform cortex and hippocampus, in the choroid plexus and in the arcuate nucleus of the hypothalamus.
View Article and Find Full Text PDFSomatostatin-14 and somatostatin-28 are biologically active peptides derived from the posttranslational cleavage of prosomatostatin. Because both peptides are found in variable concentrations in the gastrointestinal (GI) tract and pancreas, it has been contended that somatostatin-28 is either an intermediate in the processing to somatostatin-14 or a terminal product derived from prosomatostatin. To address this question, two antisera were used to recognize epitopes in two regions of somatostatin-14; one with high specificity for somatostatin-14 and the other interacting with prosomatostatin, somatostatin-28, and somatostatin-14.
View Article and Find Full Text PDFStudies of insulin binding to skeletal muscle, performed using sarcolemmal membrane preparations or whole muscle incubations of mixed muscle or typical red (soleus, psoas) or white [extensor digitorum longus (EDL), gastrocnemius] muscle, have suggested that red muscle binds more insulin than white muscle. We have evaluated this hypothesis using cryostat sections of unfixed tissue to measure insulin binding in a broad range of skeletal muscles; many were of similar fiber-type profiles. Insulin binding per square millimeter of skeletal muscle slice was measured by autoradiography and computer-assisted densitometry.
View Article and Find Full Text PDFBinding of insulin and insulin-like growth factor-I (IGF-I) to the choroid plexus was quantitatively characterized using autoradiography and computer densitometry. Slide-mounted brain slices were incubated in 0.1 nM [125I]-insulin or [125I]-[Thr59]IGF-I.
View Article and Find Full Text PDFStudies in animals indicate that methylprednisolone and naloxone are both potentially beneficial in acute spinal-cord injury, but whether any treatment is clinically effective remains uncertain. We evaluated the efficacy and safety of methylprednisolone and naloxone in a multicenter randomized, double-blind, placebo-controlled trial in patients with acute spinal-cord injury, 95 percent of whom were treated within 14 hours of injury. Methylprednisolone was given to 162 patients as a bolus of 30 mg per kilogram of body weight, followed by infusion at 5.
View Article and Find Full Text PDFLong term effects of in vivo treatment with human rIL-1 beta on diabetogenesis and thyroid disease were determined in the Biobreeding rat. Administration of high dose (10 micrograms/kg) IL-1 beta accelerated the onset of insulin-dependent diabetes mellitus compared to saline-injected controls. High dose treatment resulted in goiter development, pronounced LT, reduced serum T4 levels, and overall growth reduction.
View Article and Find Full Text PDFIn order to study the role of plasma insulin in regulating the binding of insulin to the endothelium of the blood-brain barrier (BBB), insulin binding to a purified preparation of brain capillaries was measured in both genetically obese Zucker rats and lean Zucker controls. We found a reduction of 65% in brain capillary insulin binding site number in the obese compared to lean rats with no change in receptor affinity. Furthermore, specific insulin binding to brain capillaries was negatively correlated (p less than 0.
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