Fresh Phyllanthus emblica (Amla) Fruit Supplementation Enhances Milk Fatty Acid Profiles and the Antioxidant Capacities of Milk and Blood in Dairy Cows

The objective of this study was to investigate the effect of a diet supplemented with fresh amla fruit as a natural feed additive on blood metabolic parameters, milk antioxidant capacity, and milk fatty acid (FA) proportions in lactating dairy cows. Eight ruminally cannulated mid-lactation dairy cows were used in a repeated crossover design. The first group of four cows received total mixed ration (TMR) feed without fresh amla fruit (control group). The remaining four cows sequentially supplemented fresh amla fruit (FAF) at three levels (200, 400, then 600 g/d) (treatment group) at 14-day intervals. In second period, control and treatment groups were exchanged. The first ten days were adjusted to diet adaptation for each sub-period, and the last four days for sampling milk and blood. A total of 514 metabolites were detected from FAF using UPLC-ESI-MS/MS. The five main metabolites in FAF were phenolic acids (22%), flavonoids (20%), lipids (20%), amino acids and derivatives (9%), and tannins (7%). Amla fruit supplementation reduced total saturated fatty acid and the omega-6/omega-3 ratio at 200 or 400 g/d FAF dose compared to controls. In addition, amla fruit increased unsaturated FA, such as C_20:5 (Eicosapentaenoic acid, EPA) and C_22:6 (docosahexaenoic acid, DHA), and branched-chain FA in a dose-dependent manner at 200 or 400 g/d compared to controls. In addition, amla fruit increased the antioxidant capacity biomarkers in the blood, such as superoxide dismutase (SOD) and albumin; this confirms that amla fruit is an excellent antioxidant, inhibiting reactive oxygen species’ (ROS) metabolism, and can thereby protect cells from oxidative stress. Moreover, the most remarkable improvement of ferric reducing-antioxidant power (FRAP) and total antioxidant capacity (TAC) in milk was recorded at 400 g/d FAF doses compared to controls. Therefore, fresh amla fruit doses for lactating cows at 400 g/d on an as-fed basis can be used as an alternative additive feed in dairy cow diets to improve antioxidant capacity, protein efficiency, butter quality, and to produce more desirable milk fatty acid profiles for human consumption.

Nitric Oxide Interaction with the Eye

Nitric oxide (NO) is acknowledged as a vital intercellular messenger in multiple systems in the body. Medicine has focused on its functions and therapeutic applications for decades, especially in cardiovascular and nervous systems, and its role in immunological responses. This review was composed to demonstrate the prevalence of NO in components of the ocular system, including corneal cells and multiple cells in the retina. It discussed NO's assistance during the immune, inflammation and wound-healing processes. NO is identified as a vascular endothelial relaxant that can alter the choroidal blood flow and prompt or suppress vascular changes in age-related macular degeneration and diabetes, as well as the blood supply to the optic nerve, possibly influencing the progression of glaucoma. It will provide a deeper understanding of the role of NO in ocular homeostasis, the delicate balance between overproduction or underproduction and the effect on the processes from aqueous outflow and subsequent intraocular pressure to axial elongation and the development of myopia. This review also recognized the research and investigation of therapies being developed to target the NO complex and treat various ocular diseases.

An Overview of Stroke: Mechanism, In vivo Experimental Models Thereof, and Neuroprotective Agents

BACKGROUND

Stroke is one of the causes of death and disability globally. Brain attack is because of the acute presentation of stroke, which highlights the requirement for decisive action to treat it.

OBJECTIVE

The mechanism and in-vivo experimental models of stroke with various neuroprotective agents are highlighted in this review.

METHOD

The damaging mechanisms may proceed by rapid, nonspecific cell lysis (necrosis) or by the active form of cell death (apoptosis or necroptosis), depending upon the duration and severity and of the ischemic insult.

RESULTS

Identification of injury mediators and pathways in a variety of experimental animal models of global cerebral ischemia has directed to explore the target-specific cytoprotective strategies, which are critical to clinical brain injury outcomes.

CONCLUSION

The injury mechanism, available encouraging medicaments thereof, and outcomes of natural and modern medicines for ischemia have been summarized. In spite of available therapeutic agents (thrombolytics, calcium channel blockers, NMDA receptor antagonists and antioxidants), there is a need for an ideal drug for strokes.

Highly hydrophobic polytetrafluoroethylene particle immobilization via polydopamine anchor layer on nitric oxide releasing polymer for biomedical applications

Biomedical surface-associated infections and thrombus formation are two major clinical issues that challenge patient safety and patient the fate of a medical device in the body . Single platform multifunctional surfaces are critical to address both these indwelling medical device-related problems. In this work, bio-inspired approaches are employed to fabricate a polymer composite with a versatile surface that can reduce bacterial infections and platelet adhesion in vitro. In the first bio-inspired approach, the functionality of nitric oxide (NO) produced by endothelial cell lining of blood vessels is mimicked through incorporation of S-nitroso-N-acetylpenicillamine (SNAP) within a CarboSil-2080A™ (CarboSil) polymer composite matrix. The second approach involves utilizing mussel adhesive chemistry, via polydopamine (PDA) to immobilize polytetrafluoroethylene (PTFE) particles on the polymer composite surface. The PTFE coating facilitates a decrease in wettability by making the polymer composite surface highly hydrophobic (contact angle ca. 120°). The surface of the fabricated polymer composite , CarboSil SNAP-PTFE, had a cobblestone-like structured appearance as characterized through scanning electron microscopy (SEM). Water contact angle (WCA) and surface tension measurements indicated no significant coating losses after 24 h under physiological conditions. NO surface flux was measured and analyzed for 5 days using a chemiluminescence-based nitric oxide analyzer and was found to be within the physiological range. CarboSil SNAP-PTFE reduced adhered bacteria (99.3 ± 0.5% for Gram-positive S. aureus and 99.1 ± 0.4% for Gram-negative E. coli) in a 24 h in vitro study. SEM analysis showed the absence of biofilm formation on CarboSil SNAP-PTFE polymer composites, while present on CarboSil in 24 h exposure to S. aureus. Platelet adhesion was reduced by 83.3 ± 4.5%. Overall, the results of this study suggest that a combination of NO-releasing CarboSil with PTFE coating can drastically reduce infection and platelet adhesion.

Characterization of Nitric Oxide Modulatory Activities of Alkaline-Extracted and Enzymatic-Modified Arabinoxylans from Corn Bran in Cultured Human Monocytes

The ingestion of foods and food-derived substances that may mediate the immune system is widely studied. Evidence suggests cereal arabinoxylans (AXs) have immunomodulatory activities that may impart health benefits in terms of immune enhancement. This study extracted AXs from corn bran using alkali and developed a modification process using three endoxylanases to obtain fractions of lower molecular weight ranges. In vitro studies showed extracted and modified AXs significantly (P < 0.05) elevated nitric oxide (NO) synthesis by the human U937 monocytic cell line (ranging from 53.7 ± 1.1 to 62.9 ± 1.2 μM per million viable cells) at all concentrations tested (5-1000 μg/mL), indicative of immune enhancement compared to an untreated control (43.7 ± 1.9 μM per million viable cells). The study suggested the dose range and Mw distribution of AXs are key determinants of immune-modulatory activity. AXs in the low Mw range (0.1-10 KDa) were the most effective at inducing NO secretion by U937 macrophages at low AX concentration ranges (5-50 μg/mL), with NO production peaking at 62.9 ± 1.2 μM per million viable cells with 5 μg/mL of AX (P = 0.0009). In contrast, AXs in the high Mw range (100-794 kDa) were most effective at inducing NO at high AX concentration ranges (500-1000 μg/mL) with NO production reaching a maximum of 62.7 ± 1.3 μM per million viable cells at 1000 μg/mL of AX (P = 0.0011). The findings suggest that dietary AXs from corn bran may heighten innate immune responses in the absence of infection or disease.

Immunocytogenetic effects of gonadotropin releasing hormone analogue: Triptorelin Pamoate (Decapeptyl ®) during in vitro fertilization treatment

In this study, the immunocytogenetic effects of Decapeptyl ® (Triptorelin Pamoate) were assessed in the peripheral blood lymphocytes of females undergoing in vitro fertilization (IVF) treatment. Blood samples were taken from 34 females (23 treated and 11 controls), cultured and examined for sister chromatid exchanges (SCE) and cell replication index (CRI). The SCE frequency increased around ovulation time in the controls, and around the time of human chorionic gonadotropin administration in the IVF group. However, the SCE rate was significantly higher in the latter group. Furthermore, the white blood cells (WBC) count was significantly higher on the day of ovum pick up compared to the day preceding luteinizing hormone (LH) and follicle stimulating hormone (FSH) treatment. Similar observations were recorded with respect to phagocytic activity tested by nitroblue tetrazolium (NBT) assay. The nitric oxide production abilities of macrophages were not significantly changed in the LH, FSH-treated group relative to its control. Finally, the 50% complement hemolytic activity (CH50) assay results indicated that Decapeptyl lacks a significant potential to affect the complement system.

Neurotrophic Factor Protection against Excitotoxic Neuronal Death

Neurotrophic factors are polypeptides capable of promoting neuronal survival in both the developing and the adult brain. In addition to the neurotrophins, NGF, brain-derived neurotropic factor, and NT-3 to -6, other neurotrophic factors include ciliary neurotrophic factor, fibroblast growth factors, insulin-like growth factors, members of the transforming growth factor superfamily, members of the epidermal growth factor family, and other cytokines such as leukemia inhibitory factor, oncostatin M, and interleukins-6 and -11. One condition under which these factors promote survival is the challenge of neurons with analogs of excitatory amino acid transmitters. Such analogs, including quinolinic acid, kainic acid, and ibotenic acid, are frequently employed as models of neurological diseases such as Huntington's disease, Parkinson's disease, Alzheimer's disease, epilepsy, cerebellar degenerations, and amyotrophic lateral sclerosis. Excitotoxicity also plays a role in neu ronal death caused by focal ischemia, hypoglycemia, or trauma. Although much has been learned about the mechanisms of both the action of neurotrophic factors and of cell death in response to excitotoxins, the mechanism of protection by these factors remains uncertain. This review explores the biochemical and phys iological changes mediated by neurotrophic factors that may underlie their ability to protect against excito toxic cell death. Second messenger pathways used degenerately by both excitotoxins and neurotrophic factors are discussed as a potential site of interaction mediating the protective effects of neurotrophic factors. Particular attention is also paid to the importance of the route of neurotrophic factor delivery in conferring neuroprotection in particular excitotoxic models. The Neuroscientist 1:286-297, 1995

Inhibitory effects of constituents of an endophytic fungus Hypoxylon investiens on nitric oxide and interleukin-6 production in RAW264.7 macrophages

Three new compounds, hypoxyloamide (1), 8-methoxynaphthalene-1,7-diol (2), and hypoxylonol (3), together with seven compounds isolated from nature for the first time, investiamide (4), hypoxypropanamide (5), hypoxylonol A (6), investienol (7), 2-heptylfuran (8), (3S)-5-methyl-8-O-methylmellein (9), (4R)-O-methylsclerone (10), along with 19 known compounds, 11-29, were isolated from the culture broth of Hypoxylon investiens BCRC 10F0115, a fungal endophyte residing in the stems of an endemic Formosan plant Litsea akoensis var. chitouchiaoensis. The structures of the new compounds were established by spectroscopic methods, including UV, IR, HR-ESI-MS, and extensive 1D- and 2D-NMR techniques. Of these isolates, 2, 8-methoxynaphthalen-1-ol (15), and 1,8-dimethoxynaphthalene (16) showed nitric oxide (NO) inhibitory activity with IC50 values of 11.8±0.9, 17.8±1.1, and 13.3±0.5 μM, respectively, stronger than the positive control quercetin (IC50 36.8±1.3 μM). Compounds 2, 15, and 16 also showed interleukin-6 (IL-6) inhibitory activity with IC50 values of 9.2±1.7, 18.0±0.6, and 2.0±0.1 μM, stronger than the positive control quercetin (IC50 31.3±1.6 μM). To the best of our knowledge, this is the first report on guaiane sesquiterpene metabolites, 3, 6, and 7, from the genus Hypoxylon.

In vitro anti-proliferative and anti-angiogenic activities of thalidomide dithiocarbamate analogs

Inhibition of angiogenesis is currently perceived as a promising strategy in the treatment of cancer. The anti-angiogenicity of thalidomide has inspired a second wave of research on this teratogenic drug. The present study aimed to investigate the anti-proliferative and anti-angiogenic activities of two thalidomide dithiocarbamate analogs by studying their anti-proliferative effects on human umbilical vein endothelial cells (HUVECs) and MDA-MB-231 human breast cancer cell lines. Their action on the expression levels of IL-6, IL-8, TNF-α, VEGF165, and MMP-2 was also assessed. Furthermore, their effect on angiogenesis was evaluated through wound healing, migration, tube formation, and nitric oxide (NO) assays. Results illustrated that the proliferation of HUVECs and MDA-MB-231 cells was not significantly affected by thalidomide at 6.25-100μM. Thalidomide failed to block angiogenesis at similar concentrations. By contrast, thalidomide dithiocarbamate analogs exhibited significant anti-proliferative action on HUVECs and MDA-MB-231 cells without causing cytotoxicity and also showed powerful anti-angiogenicity in wound healing, migration, tube formation, and NO assays. Thalidomide analogs 1 and 2 demonstrated more potent activity to suppress expression levels of IL-6, IL-8, TNF-α, VEGF165, and MMP-2 than thalidomide. Analog 1 consistently, showed the highest potency and efficacy in all the assays. Taken together, our results support further development and evaluation of novel thalidomide analogs as anti-tumor and anti-angiogenic agents.

Anti-inflammation effect of Exercise and Korean red ginseng in aging model rats with diet-induced atherosclerosis

BACKGROUND/OBJECTIVES

The aim of this study was to investigate the effects of exercise (EX) and Korean red ginseng (KRG) on inflammation mechanism in aging model rats with diet-induced atherosclerosis.

MATERIALS/METHODS

Forty-eight male Sprague-Dawley rats were divided into 6 groups: Young control (Y-C), Aging control (A-C), A-C with HFD (AHF), AHF with EX (AHF-EX), AHF-EX with KRG (AHF-EX+RG), and AHF with KRG (AHF-RG). Aging was induced by D-gal (100mg/kg) and atherosclerosis was induced by HFD (60% fat) for 9 weeks. The experimental rats were performed swimming (60 min/day, 5 days/week) and supplied KRG orally (dose of 200 mg/kg) for 8 weeks. All rat aorta samples were harvested for biochemical and immunohistochemical analyses.

REULTS

The EX and KRG supplementation significantly inhibited body weight and levels of TC, TG, LDL-C, and enhance of HDL-C compared with untreated AHF groups. AHF-EX, AHF-EX+RG, and AHF-RG group showed a decreased plasma CRP and increase plasma NO activities compared to AHF group. In addition, these groups revealed reduced 4-HNE, NF-kB, TNF-α, IL-6, COX-2, ICAM-1, VCAM-1 and enhanced eNOS expression in the aorta.

CONCLUSION

These results suggest that EX alone, KRG alone, and combined treatment of EX and KRG may be an effective anti-inflammatory therapeutic for the atherosclerosis, possibly acting via the decreased of CRP and pro-inflammation proteins and the increased NO and eNOS.

Effects of maternal undernutrition during late pregnancy on the development and function of ovine fetal liver

This study investigated the effects of maternal undernutrition during late pregnancy on the development and function of ovine fetal liver. Eighteen ewes with singleton fetuses were allocated to three groups at d 90 of pregnancy: Restricted Group 1 (RG1, 0.175MJMEkgBW(-0.75)d(-1), n=6), Restricted Group 2 (RG2, 0.33MJMEkgBW(-0.75)d(-1), n=6) and a Control Group (CG, ad libitum, 0.67MJMEkgBW(-0.75)d(-1), n=6). Fetuses were recovered at slaughter on d 140. Fetuses in the RG1 group exhibited decreased (P<0.05) liver weight, total antioxidant capacity (T-AOC), superoxide dismutase activity (SOD), cholinesterase (CHE), total protein (TP), globulin (GLB), and alanine transaminase (ALT). In addition, intermediate changes were found in the RG2 fetuses, including decreased liver weight, T-AOC and CHE (P<0.05). In contrast, increases in fetal hepatic collagen fibers and reticular fibers, glutathione peroxidase (GSH-Px), malondialdehyde (MDA), nitric oxide (NO), nitric oxide synthase (NOs), monoamine oxidase (MAO), albumin (ALB)/GLB, aspartate transaminase (AST), and AST/ALT were found in the RG1 fetuses (P<0.05). The RG2 fetuses had increased fetal hepatic collagen fibers, NOs and MAO (P<0.05) relative to the control fetuses. These results indicate that impaired fetal hepatic growth, fibrosis, antioxidant imbalance and dysfunction were associated with maternal undernutrition.

Anesthetics, cerebral protection and preconditioning

BACKGROUND AND OBJECTIVES

Several studies demonstrate that cerebral preconditioning is a protective mechanism against a stressful situation. Preconditioning determinants are described, as well as the neuroprotection provided by anesthetic and non-anesthetics agents.

CONTENT

Review based on the main articles addressing the pathophysiology of ischemia-reperfusion and neuronal injury and pharmacological and non-pharmacological factors (inflammation, glycemia, and temperature) related to the change in response to ischemia-reperfusion, in addition to neuroprotection induced by anesthetic use.

CONCLUSIONS

The brain has the ability to protect itself against ischemia when stimulated. The elucidation of this mechanism enables the application of preconditioning inducing substances (some anesthetics), other drugs, and non-pharmacological measures, such as hypothermia, aimed at inducing tolerance to ischemic lesions.

Protective effect of pitavastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, on ischemia-induced neuronal damage

We investigated the neuroprotective effects of a novel 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor (pitavastatin) on ischemic neuronal damage in gerbils using immunohistochemistry. The animals were allowed to survive for 14 days after 5 min of ischemia induced by bilateral occlusion of the common carotid arteries. Five days after ischemia, severe neuronal cell loss was observed in the hippocampal CA1 sector. Prophylactic treatment with pitavastatin dose-dependently prevented the hippocampal CA1 neuronal cell loss 5 days after ischemia. Immunohistochemical study did not show the change of nNOS and iNOS expression in the hippocampus except for, in a few regions, up to 1 day after ischemia. Thereafter, the expression of iNOS was observed in the hippocampal CA1 sector 5 and 14 days after ischemia. In contrast, the expression of nNOS and eNOS gradually decreased in the hippocampal CA1 sector up to 14 days after ischemia. Prophylactic treatment with pitavastatin also prevented the expression of iNOS and the decrease of eNOS expression and the number of nNOS-positive cells in the hippocampal CA1 sector 5 days after ischemia. However, prophylactic treatment with pitavastatin at a dose of 10 mg kg(-1) did not change the immunoreactivity of iNOS and nNOS in the hippocampus at an early phase after ischemia. In contrast, this drug prevented the reduction of eNOS immunoreactivity in the hippocampal CA1 neurons at an early phase after ischemia. These findings demonstrate that the HMG-CoA reductase inhibitor pitavastatin can protect hippocampal CA1 neurons after transient forebrain ischemia through up-regulation of eNOS expression in this region. Thus pharmacological modulation of eNOS expression may offer a novel therapeutic strategy for cerebral ischemic stroke.

Anesthetics, cerebral protection and preconditioning

BACKGROUND AND OBJECTIVES

Several studies demonstrate that cerebral preconditioning is a protective mechanism against a stressful situation. Preconditioning determinants are described, as well as the neuroprotection provided by anesthetic and non-anesthetics agents.

CONTENT

Review based on the main articles addressing the pathophysiology of ischemia-reperfusion and neuronal injury and pharmacological and non-pharmacological factors (inflammation, glycemia, and temperature) related to the change in response to ischemia-reperfusion, in addition to neuroprotection induced by anesthetic use.

CONCLUSIONS

The brain has the ability to protect itself against ischemia when stimulated. The elucidation of this mechanism enables the application of preconditioning inducing substances (some anesthetics), other drugs, and non-pharmacological measures, such as hypothermia, aimed at inducing tolerance to ischemic lesions.

Role of nitric oxide in cerebellar development and function: focus on granule neurons

More than 20 years of research have firmly established important roles of the diffusible messenger molecule, nitric oxide (NO), in cerebellar development and function. Granule neurons are main players in every NO-related mechanism involving cerebellar function and dysfunction. Granule neurons are endowed with remarkable amounts of the Ca(2+)-dependent neuronal isoform of nitric oxide synthase and can directly respond to endogenously produced NO or induce responses in neighboring cells taking advantage of the high diffusibility of the molecule. Nitric oxide acts as a negative regulator of granule cell precursor proliferation and promotes survival and differentiation of these neurons. Nitric oxide is neuroprotective towards granule neurons challenged with toxic insults. Nitric oxide is a main regulator of bidirectional plasticity at parallel fiber-Purkinje neuron synapses, inducing long-term depression (LTD) or long-term potentiation (LTP) depending on postsynaptic Ca(2+) levels, thus playing a central role in cerebellar learning related to motor control. Granule neurons cooperate with glial cells, in particular with microglia, in the regulation of NO production through the respective forms of NOS present in the two cellular types. Aim of the present paper is to review the state of the art and the improvement of our understanding of NO functions in cerebellar granule neurons obtained during the last two decades and to outline possible future development of the research.

Garlic provides protection to mice heart against isoproterenol-induced oxidative damage: role of nitric oxide

Garlic has been widely recognized as a cardioprotective agent. However, the molecular mechanism of its cardioprotective effects is not well established. Here we hypothesized that aqueous garlic homogenate may mediate cardioprotection via nitric oxide (NO). Mice were fed with saline and aqueous garlic homogenate (250 and 500 mgkg(-1)day(-1) orally) for 30 days. In another set of experiment, mice were pre-treated with saline, aqueous garlic homogenate (AGH) (250 mgkg(-1)day(-1) for 30 days), and AGH (30 days) along with L-NAME (20 mgkg(-1)day(-1) i.p. for last 7 days) before inducing acute myocardial infarction by isoproterenol (s.c. injection of isoproterenol 150 mgkg(-1)day(-1) for 2 days) and sacrificed after 48 h. Dose dependent increase in serum NO level was observed after garlic 250 and 500 mgkg(-1) dose feeding. While no change in serum SGPT and SGOT level, a significant decrease in serum LDH level was observed after garlic feeding. Garlic-induced NO formation was further confirmed in human aortic endothelial cells (HAEC). Administration of isoproterenol caused a significant decrease in endogenous antioxidants i.e., myocardial catalase, GSH and GPx activity, and mitochondrial enzyme activities like citrate synthase and β hydroxyacyl CoA dehydrogenase. All those deleterious cardiac changes induced by isoproterenol were significantly attenuated by garlic homogenate. However this beneficial effect of garlic was blunted when garlic was administered with L-NAME, a nonspecific inhibitor of nitric oxide synthase (NOS). Further, a significant increase in myocardial TBARS and decrease in total antioxidant activity was observed in L-NAME treated group compared to isoproterenol treated group. Administration of L-NAME in mice from control group lowered serum and cardiac NO levels without any change of oxidative stress parameters. In conclusion, our study provides novel evidence that garlic homogenate is protective in myocardial infarction via NO-signaling pathway in mice.

Inhibition of endogenous CO by ZnPP protects against stress-induced gastric lesion in adult male albino rats

Carbon monoxide (CO) has been found to be produced in every living cell in a biochemical reaction catalyzed by heme-oxygenase (HO) enzyme which degrades heme into biliverdin, CO, and iron. Endogenous CO is not a waste product, but acts as a chemical messenger mediating and modulating many intracellular biochemical reactions that regulate physiological functions. This study was designed to investigate the effect of inhibition of endogenous CO production by zinc protoporphyrin (ZnPP), an HO inhibitor, on the gastric secretion and ulceration induced by cold-restraint stress (CRS) in adult male albino rats. Rats were pylorically ligated and divided randomly into the following groups (six rats each): control, ZnPP treated (50 μmol/kg/day, s.c. for 10 days), CRS, and stressed ZnPP treated groups. Blood samples were collected from the retro-orbital sinus of anesthetized rats for determination of CO concentration. We found that ZnPP pretreatment significantly decreased HO-1 level, CO level, and volume of gastric juice as compared to the control non-stressed rats. In the present study, ZnPP pretreatment proved to be protective against development of ulcerative lesions in CRS model as evidenced by reduction of the ulcer index, and this could be mediated through reduction of free and total acidity of gastric secretion and decreased lipid peroxidation but with significantly decreased gastric protective nitric oxide and prostaglandin E(2) levels. In conclusion and according to our results, the protective effect of ZnPP on CRS-induced gastric ulcers despite of inhibition of endogenous CO could be attributed to the presence of zinc which is known to have a protective anti-ulcer effect.

Hepatoprotective activity of Stereospermum suaveolens against CCl4-induced liver damage in albino rats

The present study aims to evaluate the hepatoprotective activity of Stereospermum suaveolens DC (Bignoniaceae). Hepatoprotective activity is studied by carbon tetrachloride (CCl(4))-induced liver damage in albino rats. The degree of protection in this activity has been measured by using biochemical parameters such as serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alkaline phosphatase (ALP), total bilirubin, LDL-cholesterol and SOD, CAT, GSH, total thiols, NO, and lipid peroxidation in liver tissue homogenate. The results suggest that the methanol stem bark extract of Stereospermum suaveolens at the doses 125, 250, and 500 mg/kg and reference standard Liv-52 treated group produced significant (p <0.001) hepatoprotection against CCl(4)-induced liver damage by decreasing the activities of serum enzymes, bilirubin and lipid peroxidation. The extract significantly (p <0.001) increased levels of SOD, CAT, GSH and total thiols, as compared to control group. Histopathological studies further substantiate the protective effect of the extract. It was concluded that methanol stem bark extract of Stereospermum suaveolens showed effective hepatoprotective activity.

Subclinical mastitis causes alterations in nitric oxide, total oxidant and antioxidant capacity in cow milk

The aim of this study was to investigate total antioxidant (TAC), and oxidant capacity (TOC) and nitric oxide (NO) levels in milk of cows with subclinical mastitis. Brown Swiss and Holstein breed cows were screened with California Mastitis Test (CMT) to determine mammary glands with subclinical mastitis. Moreover, somatic cell counts (SCC) were determined electronically in all milk samples. Mammary quarters were classified as healthy (n=25) or subclinical mastitis (n=35) based on CMT scores and somatic cell count (SCC: < or =200,000/ml or >200,000/ml) in milk. Nitric oxide, TOC and SCC levels were significantly higher (p<0.001, p<0.005 and p<0.001, respectively) in milk from mammary quarters with subclinical mastitis compared to those from healthy mammary quarters. In conclusion, subclinical mastitis results in higher NO concentrations, TOC and SCC, and NO and TOC were positively correlated with SCC. Moreover, alterations in NO levels and TOC in milk could be used as an alternative diagnostic tool to screen for subclinical mastitis.

Nitric oxide and lysozyme production as an impact to Clostridium perfringens mastitis

The anaerobic mastitis incidence was used to study the bovine udder response in anaerobic bacterial mastitis caused by the Gram-positive bacterial strain of Clostridium perfringens. Milk samples positive for C. perfringens were assayed for NO and lysozyme. The model produced a strong NO and lysozyme response which correlated positively with the severity and outcome of the disease (subclinical and clinical stages). This study is, to our knowledge, the first to suggest a possible link between NO and lysozyme and bovine mastitis caused by C. perfringens. The results raise the possibility that interfering with NO production during mastitis may help to prevent tissue damage.

Selenium and vitamin E increases polymorphonuclear cell phagocytosis and antioxidant levels during acute mastitis in riverine buffaloes

Antioxidant, antiinflammatory and phagocytic activities were studied in milk polymorphonuclear cells (PMNs) isolated from healthy buffaloes (group I) and during clinical mastitis with the treatment of Enrofloxacin alone (group II) and combined treatment with Enrofloxacin and Vitamin E plus selenium (group III). On days 0,3, 8 and 15 the milk Somatic cell count (SCC) were significantly higher in mastitic milk than in milk obtained from healthy buffaloes. In group II SCC decreased significantly on day 3 and day 8, however in group III reduction in SCC was observed on day 3, day 8 and day 15 (P < 0.05). The antiinflammatory activity was evaluated by determining nitrite plus nitrate (NOx) production in the milk PMNs before treatment and on day 8. NOx activity was significantly higher in mastitic milk than from healthy controls, both before and after treatment (P < 0.05). In group II and group III the activity decreased significantly on day 8 (P < 0.05). The Glutathione peroxidase (GSH-Px) activity was estimated in the milk polymorphonuclear cell (PMNs) supernatant. GSH-Px activity was significantly lower in mastitic buffaloes than in healthy controls, both before and after treatment (P < 0.05). In group II levels did not change in response to treatment, whereas in group III levels had increased significantly on day 8 (P < 0.05). The phagocytic activity (PA) (percentage of neutrophil that had phagocytosed 1-6 bacteria) and phagocytic index (PI) (average number of bacteria/ leukocytes counted in 100 cells) of the milk PMNs was significantly lower in mastitic buffaloes (P < 0.05). In group II the PA and PI did not change in response to treatment, whereas in group III both the parameters had increased significantly on day 8 (P < 0.05). The results of the present experiment indicated enhancement of antioxidative and cellular defense and reduction of somatic cell count in the mastitic animals treated with Enrofloxacin and Vitamin E plus Selenium as compared to the Enrofloxacin treatment alone. Hence Vitamin E plus selenium therapy may be added along with the antibiotics for effective amelioration of intramammary infection in buffaloes.

Anti-inflammatory mechanisms of apigenin: inhibition of cyclooxygenase-2 expression, adhesion of monocytes to human umbilical vein endothelial cells, and expression of cellular adhesion molecules

The aim of this study was to clarify the anti-inflammatory mechanism of apigenin. Apigenin inhibited the collagenase activity involved in rheumatoid arthritis (RA) and suppressed lipopolysaccharide (LPS)-induced nitric oxide (NO) production in a dose dependent manner in RAW 264.7 macrophage cells. Pretreatment with apigenin also attenuated LPS-induced cyclooxygenase-2 (COX-2) expression. In addition, apigenin profoundly reduced the tumor necrosis factor-alpha (TNF-alpha)-induced adhesion of monocytes to HUVEC monolayer. Apigenin significantly suppressed the TNF-alpha-stimulated upregulation of vascular cellular adhesion molecule-1 (VCAM-1)-, intracellular adhesion molecule-1 (ICAM-1)-, and E-selectin-mRNA to the basal levels. Taken together, these results suggest that apigenin has significant anti-inflammatory activity that involves blocking NO-mediated COX-2 expression and monocyte adherence. These results further suggest that apigenin may be useful for therapeutic management of inflammatory diseases.

Peroxynitrite: In vivo and In vitro synthesis and oxidant degradative action on biological systems regarding biomolecular injury and inflammatory processes

This review summarizes all significant data regarding peroxynitrite chemistry, the ways of its synthetic preparation as well as the degradative action of this species on biomolecules, in particular glycosaminoglycans, among which the hyaluronan degradation by peroxynitrite has recently been the subject of greater interest than ever before. The complex chemical behavior of a peroxynitrite molecule is strongly influenced by a few factors; conformational structural forms, active intermediates release, presence of CO2 and trace transition metals, different reaction conditions, as well as the rules of kinetics. Special attention was focused on monitoring of the kinetics of the degradative action of peroxynitrite in or without the presence of residual hydrogen peroxide on high-molar-mass hyaluronan.

Differential regulation of the neuronal isoform of nitric oxide synthase in the superior colliculus and dorsal lateral geniculate nucleus of the adult rat brain following eye enucleation

Nitric oxide has been shown to play various physiological and pathological roles in the visual system. We studied here the expression of the neuronal isoform of nitric oxide synthase in the rat superior colliculus and in the dorsal lateral geniculate nucleus after unilateral enucleation, by means of immunohistochemistry, immunoblotting, and real-time PCR. Immunohistochemistry revealed an increase of nitric oxide synthase-positive neurons in specific layers of the superior colliculus and in the dorsal lateral geniculate nucleus between 1 and 30 days post-lesion. Immunoblotting analyses confirmed that the neuronal isoform of nitric oxide synthase is upregulated in the superior colliculus and in the dorsal lateral geniculate nucleus after retinal removal. Diaminofluorescein histochemistry suggested that nitric oxide production was increased in both deafferented retinorecipient areas. Our real-time PCR results indicated that nitric oxide synthase transcript levels in the superior colliculus were not significantly altered after monocular enucleation, although an upregulation of the enzyme transcription was detected into the deafferented dorsal lateral geniculate nucleus. These findings indicated that neuronal nitric oxide synthase may undergo different forms of regulation in the adult deafferented visual system.

Mechanisms of Brain Injury after Global Cerebral Ischemia

Cerebral ischemia results in a rapid depletion of energy stores that triggers a complex cascade of cellular events such as cellular depolarization and Ca2+ influx, resulting in excitotoxic cell death. The critical determinant of severity of brain injury is the duration and severity of the ischemic insult and early restoration of CBF. Induced therapeutic hypothermia following CA is the only strategy that has demonstrated improvement in outcomes in prospective, randomized clinical trials. Although pharmacologic neuro-protection has been disappointing thus far in a variety of experimental animal models, further research efforts are directed at using some agents that demonstrate marginal or moderate efficacy in combination with hypothermia. Although the signal transduction pathways and intracellular molecular events during cerebral ischemia and reperfusion are complex, potential therapeutic neuroprotective strategies hold promise for the future.

Alterations of interneurons of the gerbil hippocampus after transient cerebral ischemia: effect of pitavastatin

We investigated the immunohistochemical alterations of parvalbumin (PV)-expressing interneurons in the hippocampus after transient cerebral ischemia in gerbils in comparison with neuronal nitric oxide synthase (nNOS)-expressing interneurons. We also examined the effect of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor pitavastatin against the damage of neurons and interneurons in the hippocampus after cerebral ischemia. Severe neuronal damage was observed in the hippocampal CA1 pyramidal neurons 5 and 14 days after ischemia. The PV immunoreactivity was unchanged up to 2 days after ischemia. At 5 and 14 days after ischemia, in contrast, a conspicuous reduction of PV immunoreactivity was observed in interneurons of the hippocampal CA1 sector. Furthermore, a significant decrease of PV immunoreactivity was found in interneurons of the hippocampal CA3 sector. No damage of nNOS-immunopositive interneurons was detected in the gerbil hippocampus up to 1 day after ischemia. Thereafter, a decrease of nNOS immunoreactive interneurons was found in the hippocampal CA1 sector up to 14 days after ischemia. Pitavastatin significantly prevented the neuronal cell loss in the hippocampal CA1 sector 5 days after ischemia. Our immunohistochemical study also showed that pitavastatin prevented significant decrease of PV- and nNOS-positive interneurons in the hippocampus after ischemia. Double-labeled immunostainings showed that PV immunoreactivity was not found in nNOS-immunopositive interneurons of the brain. The present study demonstrates that cerebral ischemia can cause a loss of both PV- and nNOS-immunoreactive interneurons in the hippocampal CA1 sector. Our findings also show that the damage to nNOS-immunopositive interneurons may precede the neuronal cell loss in the hippocampal CA1 sector after ischemia and nNOS-positive interneurons may play some role in the pathogenesis of cerebral ischemic diseases. Furthermore, our present study indicates that pitavastatin can prevent the damage of interneurons in the hippocampus after cerebral ischemia. Thus, our study provides valuable information for the pathogenesis after cerebral ischemia.

Increased expression of nitric oxide synthase in visual structures of the chick brain after retinal removal

Nitric oxide (NO) seems to act as a retrograde messenger in the establishment and refinement of synaptic connections during development and in neural plasticity processes in adult life. Previous studies have shown that the expression of NO synthase (NOS) in the optic tectum of developing chicks is regulated by the retinal innervation. The aim of this study was to observe the effects of unilateral retinal lesions upon the expression of NOS in central visual areas of the adult chick brain. After different survival times (1-30 days), the chick brains were submitted to immunohistochemical, immunoblotting, and NO imaging procedures to evaluate NOS expression and activity. Our results indicate that NOS expression in visual areas is also regulated by retinal innervation in the adult chick. However, differently from the case in the developing animal, the deafferentation seems to generate an increase of the NOS expression in retinorecipient visual areas. Our results suggest that NOS expression in visual structures of the adult chick brain may be down-regulated by the retinal innervation. Alternatively, the increase of NOS expression observed after retinal removal could be an indicative of a role of the NO system in plasticity processes.

Mechanisms of ischemic brain damage

Neurologic complications from cerebral ischemia occur frequently following cardiac arrest, as well as in the perioperative period in cardiac surgery. The cellular and molecular mechanisms of cerebral ischemia are complex. This article discusses several important cell death and salvage pathways that are important in experimental cerebral ischemia that may be critical to outcome in clinical brain injury.

Nitric oxide protects neuroblastoma cells from apoptosis induced by serum deprivation through cAMP-response element-binding protein (CREB) activation

The transcription factor cAMP-response element-binding protein (CREB) mediates survival in many cells, including neurons. Recently, death of cerebellar granule neurons due to nitric oxide (NO) deprivation was shown to be accompanied by down-regulation of CREB activity (). We now provide evidence that overproduction of endogenous NO or supplementation with exogenous NO renders SK-N-BE human neuroblastoma cells more resistant to apoptosis induced by serum deprivation. Parental cells underwent apoptosis after 24 h of serum deprivation, an outcome largely absent in clones overexpressing human neuronal nitric oxide synthase (nNOS). This protective effect was reversed by the inhibition of NOS itself or soluble guanylyl cyclase, pointing at cGMP as an intermediate effector of NO-mediated rescue. A slow-releasing NO donor protected parental cells to a significant extent, thus confirming the survival effect of NO. The impaired viability of serum-deprived parental cells was accompanied by a strong decrease of CREB phosphorylation and transcriptional activity, effects significantly attenuated in nNOS-overexpressing clones. To confirm the role of CREB in survival, the ectopic expression of CREB and/or protein kinase A largely counteracted serum deprivation-induced cell death of SK-N-BE cells, whereas transfection with a CREB negative mutant was ineffective. These experiments indicate that CREB activity is an important step for NO-mediated survival in neuronal cells.

Nitric oxide regulates cGMP-dependent cAMP-responsive element binding protein phosphorylation and Bcl-2 expression in cerebellar neurons: implication for a survival role of nitric oxide

Nitric oxide (NO) is a small, diffusible, highly reactive molecule with a dichotomous regulatory role in the brain: an intra- and intercellular messenger under physiological conditions and a neurodegenerative agent under pathological conditions. We have recently demonstrated that long-lasting exposure to an neuronal nitric oxide synthase (nNOS) inhibitor down-regulated serine/threonine kinase (Akt) survival pathway and caused apoptosis in cerebellar granule cell cultures. The present study further substantiates the role of NO in neuronal survival by demonstrating that blocking its production down-regulates the activity of cAMP-responsive element binding protein (CREB), a transcription factor involved in cell survival and synaptic plasticity. Pharmacological dissection of the pathway linking NO to CREB shows that cGMP and its kinase are intermediate effectors. We also identify Bcl-2 as one of the anti-apoptotic genes down-regulated by NO shortage and decreased CREB phosphorylation. These results not only confirm the role of CREB in neuronal survival but also provide circumstantial evidence for a novel link among NO, CREB activation and survival.

Regional alterations of the NO/NOS system in the aging brain: a biochemical, histochemical and immunochemical study in the rat

We have used several approaches (immunohistochemistry and enzyme histochemistry, Western blotting, biochemical assay of Ca(2+)-dependent catalytic activity) in order to detect differences in neuronal nitric oxide synthase (nNOS) expression and activity in various brain regions of young-adult (4-month-old) and aged (28-month-old) rats. In most of the brain regions examined (striatum, neocortex, olfactory cortex and hippocampus) some significant decrease in the density per unit area of nNOS neurons, detected either through immunohistochemistry or enzyme histochemistry, was observed in aged rats. However, only in the striatum and olfactory cortex this was accompanied by a significant decrease of the catalytic activity of the constitutive, Ca(2+)-dependent NOS form. In these two regions, the relative level of expression of nNOS protein was also significantly decreased, as assessed by Western blotting of proteic extracts from young-adult and aged rats. Other observed differences were a paler stain of neurons in some brain areas of the aged rats and differences of cellular compartmentalization of the protein in the same rats, as assessed through confocal microscopy. The present observations demonstrate that the expression and activity of nNOS show regionally-specific alterations in the brain of aged healthy rats, with a trend towards decrease, rather than toward increase as suggested by some previous reports. Therefore, hypotheses implicating nitric oxide increase in brain aging should be reconsidered on the basis of a clear-cut distinction between the physiological and the pathological aspects of the aging process.

Sustained, long-lasting inhibition of nitric oxide synthase aggravates the neural damage in some models of excitotoxic brain injury

Brain nitric oxide (NO) can be a mediator of physiological and neuroprotective actions and an effector of neural damage. The effectiveness of acute or chronic inhibition of NO production in in vivo experiments of neurotoxicity/neuroprotection is controversial. We report here on the effects of a chronic, sustained inhibition of nitric oxide synthase (NOS) on the neurodegenerative damage caused by three different excitotoxic lesions. The damage caused by intrastriatal injection of ibotenic or kainic acid was aggravated in rats subjected to chronic NOS inhibition. On the contrary, the drop of cortical cholinergic input consequent to ibotenic acid-mediated degeneration of basal forebrain neurons was not altered by chronic NOS inhibition. The worsening of the damage was not related to any overt differential sensitivity to excitotoxicity of NOS-containing striatal neurons under conditions of NOS inhibition. These results suggest that, contrary to what has been often reported for short-term, mild inhibition of NO production, chronic and sustained NOS inhibition may exacerbate neuropathology. Thus, long-lasting shortage of NO may be detrimental when neuroprotective mechanisms related to the physiological action of this free radical are severely impaired. Although we cannot exclude that inhibition of the endothelial NOS isoform could have contributed to the worsening of neuropathology, differences among the paradigms of neurotoxicity used in the present study suggest a primary involvement of the neuronal NOS isoform. In view of the potential therapeutic use of NOS inhibitors, the effects of a too drastic alteration of the balance between neuroprotective and neurodegenerative actions of NO should be carefully considered.

Induction of nitric oxide production by bovine mammary epithelial cells and blood leukocytes

A recent study from our laboratory has shown that significant amounts of nitric oxide are released by somatic cells recovered during endotoxin-induced mastitis. The present study was undertaken to investigate which cell type(s) among milk somatic cell population can produce nitric oxide under inflammatory conditions. Nitric oxide release from mammary epithelial cell lines and from bovine neutrophils and monocytes extracted from blood was measured in response to cytokines and Escherichia coli lipopolysaccharides. An epithelial cell line isolated from bovine mammary gland, FbE cells, was found to release nitric oxide after exposure to interleukin-1beta. This nitric oxide production was completely abolished by addition of L-N6-(1-iminoethyl) lysine, a potent inducible nitric oxide synthase inhibitor. Bovine monocytes produced nitric oxide in response to recombinant bovine interferon-gamma alone or in combination with E. coli lipopolysaccharides. In these cells, nitric oxide release was reduced by the addition of inducible nitric oxide synthase inhibitors L-N6-(1-iminoethyl) lysine and aminoguanidine. Lipopolysaccharides and recombinant bovine interferon-gamma increased nitric oxide synthase mRNA in neutrophils, but nitric oxide release could not be detected under any of the experimental conditions used. These results show that bovine epithelial cells and mononuclear phagocytes produce nitric oxide under inflammatory conditions and suggest that these cell populations are responsible for nitric oxide release observed during mastitis.

Role of nitric oxide in the secondary expansion of a cortical brain lesion from cold injury

We have investigated the role of nitric oxide (NO) as mediator of the secondary growth of a traumatic cortical necrosis. For this purpose, a highly standardized focal lesion of the brain was induced in 46 Sprague-Dawley rats by cold injury. Twenty-four hours later--the timepoint of maximal lesion spread--the animals were sacrificed and brains were removed for histomorphometry of the maximal necrosis area and volume. The animals were divided into five experimental groups. Group I received the NO donor L-arginine as i.v. bolus 10 min prior to trauma (300 mg/kg body weight; n = 10) and a second bolus of the same dosage intraperitoneally 1 h after trauma. Group II (n = 10)--serving as control of group I--was infused with an i.v. bolus of 1 mL/kg isotonic saline 10 min prior to and a subsequent bolus i.p. 1 h after trauma. Group III (n = 8) received 100 mg/kg b.w. of the inducible NOS (iNOS) inhibitor aminoguanidine (AG) 1 h before and 8 h after trauma by intraperitoneal route. Group IV was administered with the nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine (L-NNA; 100 mg/kg b.w., i.p.; n = 8); group V--the controls of group III and IV--was administered with isotonic saline (1 mL/kg b.w. i.p.; n = 10) 1 h before and 8 h after trauma. In the control group with i.v./i.p. sham treatment (II), the focal lesion led to a cortical necrosis with a maximum area of 3.1 +/- 0.3 mm2 and a lesion volume of 5.7 +/- 0.5 mm3 at 24 h after trauma. In animals with administration of L-arginine, the focal lesion had a maximum area of 3.1 +/- 0.3 mm2 and a volume of 5.3 +/- 0.5 mm3. Hence, the NO donor did not affect the secondary growth of necrosis. Animals with i.p. sham treatment (group V) had a maximal lesion area of 3.6 +/- 0.2 mm2 and lesion volume of 6.2 +/- 0.4 mm3. Administration of aminoguanidine afforded significant attenuation of the lesion growth. Accordingly, the maximal area of necrosis spread only to 2.8 +/- 0.2 mm2 with a volume of 4.5 +/- 0.5 mm3, respectively, at 24 h after trauma (p < 0.01 vs group V). On the other hand, administration of L-NNA did not influence the maximal lesion area (3.7 +/- 0.2 mm2) or lesion volume (6.5 +/- 0.5 mm3) evolving at 24 h after trauma. Thus, neither the enhancement of the formation of NO by L-arginine nor gross inhibition of the synthesis of NO by L-NNA did affect the secondary spread of the necrosis from a focal trauma. The marked attenuation of the posttraumatic necrosis growth by the iNOS inhibitor aminoguanidine strongly indicates an important role of iNOS product in this phenomenon. These findings, thus, demonstrate that the expansion of a primary necrotic focal lesion is a secondary process which can be therapeutically inhibited. Thereby, the growth of a focal tissue necrosis from trauma is clearly identified as a manifestation of secondary brain damage. This information is deemed important for the better understanding of the pathophysiology of traumatic brain injury and for the targeted development of specific treatment modalities.

Increased nitric oxide synthase activity in a model of serotonin depletion

Serotonin (5HT) containing cell bodies are localized in mesencephalic and rhombencephalic raphe nuclei. It has been proposed that 5HT could be involved in neuronal development and plasticity. In the central nervous system, nitric oxide (NO) has been postulated as a neurotransmitter and neuromodulator, and has been implicated in neurotoxicity as well as in neuroprotection. Using the nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) technique, NO synthesizing neurons were described in raphe nuclei. By immunohistochemistry, nitric oxide synthase (NOS) was found colocalized with 5HT in some dorsal raphe nucleus (DRN) neurons. In a model of inhibition of 5HT synthesis produced by daily administration of parachlorophenilalanine during 14 days, we have studied the relationship between 5HT and NO systems after 5HT depletion by histochemical and immunocytochemical methods. After the treatment, we observed an important reduction of 5HT immunostaining in the DRN and enhanced NOS activity demonstrated by NADPH-d technique, especially in the dorsomedial and ventromedial subgroups. In spite of the increased NOS activity, we could not observe significant changes in the NOS-immunoreactivity in the DRN after 5HT depletion. These results could indicate that 5HT depletion is concomitant with changes in NOS activity without affecting NOS expression in the DRN.

Prenatal alcohol exposure decreases the number of nitric oxide synthase positive neurons in rat superior colliculus and periaqueductal gray

Because nitric oxide (NO) is involved in the development and refinement of axonal projections and synapses, it is of interest to know if developmental alcohol exposures affect NO producing neurons. Pregnant rats were fed artificial liquid diet throughout gestation as the only fluid or caloric source. The diet for experimental dams contained ethanol (6.7% v/v) while the pair-fed diet for control dams contained isocaloric maltose-dextrin instead of ethanol. This ethanol diet regime is known to produce peak blood alcohol concentrations of approximately 140 mg%. Cells stained histochemically for nitric oxide synthase (NOS) were counted at postnatal day 15 (P15) and 35 (P35) in cross-sections of the stratum griseum superficiale (SGS) of the superior colliculus (SC) and in the dorsolateral column of the periaqueductal gray (dlPAG). Compared to control tissues, alcohol caused the following effects: In the SC, the areal density of NOS+ neurons was decreased 24% at P15 but a similar decrease in means at P35 was not statistically significant (P=0.10); soma size was unaffected at either P15 or P35. In the dlPAG, both the areal density and the total number of NOS+ neurons per section were unaffected at P15 but were decreased at P35 (33% and 37% decreases); soma size was unaffected at either P15 or P35. The decrease in NOS+ neurons in the SC at P15 could be expected to have a negative impact on the refinement of neuronal connections while the decreases in NOS+ neurons in the dlPAG at P35 likely represent more permanent effects that could alter the function of that nucleus.