Effects of honeycomb extract on the growth performance, carcass traits, immunity, antioxidant function and intestinal microorganisms of yellow bantam broilers.

Although many studies have already described the physiological effects of bee products, such as honey, propolis, pollen, and royal jelly, on livestock farming, the health benefits of the honeycomb are still not fully understood. The problem of drug residues and bacterial resistance caused by the abuse of antibiotics is becoming increasingly serious. For this reason, a safe, green substitute has to be sought. We conducted a comparative study of honeycomb extract (HE) and an antibiotic on growth performance, carcass traits, immunity, antioxidant function and intestinal microorganisms of yellow bantam broilers. A total of four hundred eighty 21-day-old female yellow bantam broilers were randomly divided into 5 groups of 6 replicates of 16 birds each. The 5 groups were as follows, with birds receiving a basal diet supplemented with 150 ppm (mg/kg) of chlortetracycline (CTE), a basal diet without HE (control group), and a basal diet with 0.1%, 0.15%, or 0.2% HE for 60 days. The results showed that HE addition significantly increased average daily feed intake (ADFI), average daily gain (ADG), decrease feed gain ratio (F/G) from 21 to 80 and 51 to 80 days of age compared to the control group, with all 3 HE addition groups having statistically identical values to the antibiotic group. HE implementation dramatically increased spleen index, serum immunoglobulin A (IgA), immunoglobulin M (IgM,), glutathione peroxide (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and total cecum bacteria and Lactobacillus compared to the control group, numerically at the same level as, or even better than, the antibiotic group. HE and CTE both markly reduced serum malondialdehyde (MDA) concentration compared to the control group, with higher concentrations of HE reducing the effect more dramatically than antibiotics. Both HE and CTE significantly raised dressed yield compared to the control group. In summary, HE, as a potential antibiotic alternative, improved growth performance, carcass traits, immune function, serum antioxidant capacity and intestinal microorganisms in yellow bantam broilers. According to the cubic regression analyses, the recommended supplemental dose of HE was calculated to be 0.15 to 0.17% for female yellow bantam broilers between 21 and 80 d of age.

Effect of supplementing hydroxy selenomethionine on meat quality of yellow feather broiler.

This study was conducted to evaluate the effect of supplementing hydroxy selenomethionine (OH-SeMet) on performance, selenium (Se) deposition in the breast muscle, quality and oxidative stability, and expression of selenoprotein encoding genes of breast meat of the native slow-growing yellow-feathered broiler birds. A total of 375 one-day-old local yellow male birds were randomly assigned into 5 dietary treatments, supplemented with Se 0.0, 0.2, 0.4, 0.6, and 0.8 mg/kg in the form of OH-SeMet. Each treatment consisted of 5 replicates and each replicate had 15 birds, the birds were fed on basal diet containing corn and soybean meal, and the experiment lasted for 63 d. The results showed that dietary Se supplementation linearly increased (P < 0.001) Se contents in both serum and muscle, no significant changes (P > 0.05) were observed on growth performance, yield of breast, meat color, and intramuscular fat deposition of the breast muscle. Dietary Se addition improved water-holding capacity, the pH24h value, and tenderness of breast muscle, evidenced by a linear decreases of shear force (P < 0.05), accompanied by lower thiobarbituric acid reactive substances and higher glutathione reductase activity. The mRNA abundance of selenoprotein encoding genes also responded to dietary Se levels. It is concluded that, dietary supplementation with OH-SeMet improved muscular Se deposition and meat quality of the native yellow birds, with enhanced antioxidant capability and regulation in selenogenome.

Effects of dietary chromium propionate on laying performance, egg quality, serum biochemical parameters and antioxidant status of laying ducks under heat stress.

Recent studies have shown that chromium (Cr) could alleviate the negative effects of heat stress on livestock and poultry, but there is little information available to laying ducks. This study aimed to investigate the effects of dietary addition of chromium propionate on laying performance, egg quality, serum biochemical parameters and antioxidant status of laying ducks under hot (average 32 °C) and humid (average 75% relative humidity) summer conditions. A total of 900 66-week-old weight- and laying-matched Shanma laying ducks were randomly divided into five treatments, each with 6 replicates of 30 individually caged birds. The birds were fed either a basal diet or the basal diet supplemented with either 200, 400, 600, or 800 µg/kg Cr as chromium propionate. All laying ducks were given feed and water ad libitum for 5 weeks. The results showed that dietary supplementation with chromium propionate significantly increased the laying rate and yolk colour score (P < 0.05). Treatment with 400 µg/kg Cr as chromium propionate significantly decreased the feed/egg ratio by 5.4% (P < 0.05). Increased supplemental Cr from 0 to 800 µg/kg resulted in an increase in albumen height and the Haugh unit linearly (P < 0.05). Increased supplemental Cr decreased serum cortisol (P < 0.001, linear; P = 0.008, quadratic), heat shock protein-70 (P < 0.001, linear; P = 0.007, quadratic) and glucose (P = 0.007, linear), whereas it increased serum insulin (P = 0.011, Linear), total protein (P = 0.006, linear; P = 0.048, quadratic) and albumin (P = 0.035, linear; P = 0.088, quadratic). Dietary Cr levels increased the activities of superoxide dismutase and glutathione peroxidase, the total antioxidant capacity linearly and quadratically (P < 0.05). A linear and quadratic (P < 0.05) decrease of the malondialdehyde concentrations in response to dietary Cr level was observed. These results indicated that dietary supplementation of Cr as chromium propionate, particularly at 800 µg/kg could beneficially affect the laying rate, egg quality and antioxidant function, as well as modulate the blood biochemical parameters of laying ducks under heat stress conditions.

Efficacy of low-level laser therapy in pain management after root canal treatment or retreatment: a systematic review.

The aim of this study was to assess the effectiveness of low-level laser therapy (LLLT) for pain management after root canal treatment or retreatment. An electronic search for randomized controlled trials was conducted prior to November 2018, through PubMed, EMBASE, the Cochrane library (CENTRAL), and Web of Science. After filtering, seven articles were included, five related to root canal therapy (RCT) and two related to root canal retreatment (RCR). Six of the included studies presented a moderate risk of bias and a one low risk of bias, based on the Cochrane tool of risk of bias evaluation. The laser treatment included diode laser and indium-gallium-aluminum laser. LLLT was compared with placebo, blank, and ibuprofen treatment. Clinical outcome variables included the prevalence of pain, pain intensity, and need for analgesics after treatment. Three studies showed LLLT could reduce the prevalence of pain significantly after RCT or RCR. Although the effect of LLLT on pain intensity varied at different observation time points and among different studies, most of them found patients had lower pain intensity in the LLLT group. Of the three studies that assessed the need for analgesics after treatment, two studies showed significant benefits. Based on the current evidence, the use of LLLT for pain control in postendodontic therapy may be promising. However, solid conclusions should not be drawn definitely, given that more high-quality randomized controlled trials are required to further evaluate the efficacy of LLLT for pain management after RCT and RCR.

Quick rehabilitation nursing improves the recovery of colon cancer patients after laparoscopy.

Colon cancer is a common malignant tumor with particularly high morbidity and mortality. The aim of this study was to compare the effect of quick rehabilitation nursing and routine nursing in postoperative recovery of patients with colon cancer after laparoscopic surgery. Two hundred forty patients with colon cancer were classified into four random groups (A, B, C and D, with 60 patients in each group). All patients underwent surgery to remove the colon tumor by laparoscopy under general anesthesia. Patients in groups A and B received quick rehabilitation nursing for post-surgery recovery. In group C patients, local anesthesia associated with quick rehabilitation nursing for post-surgery recovery was used. Group D was used as control group and the patients were treated based on routine nursing. Time to get out of bed, first bowel movement time and the average time of hospitalisation in group A was lower than group D (p less than 0.05), postoperative leukocyte level as well as the occurrence rate of nausea and vomiting, ankylenteron and pelvic adhesion was decreased in group A compared to group D (p less than 0.05), but the postoperative albumin and total protein level was higher than group D (p less than 0.05). The serum level of C-Reactive Protein (CRP) and interleukin 6 (IL-6) in group A was decreased compared to group D several days after surgery (p less than 0.05); group B had 4 cases of intestinal obstruction after surgery that could be cured through conservative treatment, while group D had 10 cases of intestinal obstruction, 8 of which could be cured through conservative treatment and two needed surgery (p less than 0.05); VAS for pain degree of group C in active state was clearly lower at 1h, 5h, 7h, 15h, 30h and 42h after surgery, and side effects of postoperative analgesia were clearly reduced. Time to get out of bed was obviously decreased, while there was no evident effect on postoperative dosage, chronic pain and complications. Adopting quick rehabilitation nursing can effectively reduce occurrence of complications and postoperative pain, speed up the recovery of gastrointestinal function, shorten the length of stay, and improve patients’ satisfaction.

Dietary linseed oil in the maternal diet affects immunoglobulins, tissue fatty acid composition and expression of lipid metabolism-related genes in piglets.

This experiment investigated the effects of supplementing the maternal diet with linseed oil (LSO) and soya bean oil (SBO) on immunoglobulins, the fatty acid composition and hepatic expression of lipid metabolism-related genes in piglets. Multiparous sows (twenty-four per diet) were fed on diets containing a supplement of either SBO or LSO during last week of gestation and lactation. The results indicated that supplementation of maternal diet with LSO could improve the weaning weight of piglets and average daily gain (ADG) (p < 0.05). The concentration of immunoglobulin G (IgG) and immunoglobulin A (IgA) was enhanced in sow plasma, colostrum and milk by the addition of LSO (p < 0.05). In addition, the concentration of 18: 3n-3 fatty acids was higher in the milk of LSO sows. Meanwhile, maternal supplementation with LSO increased the levels of plasma IgG, IgA and the tissues n-3 polyunsaturated fatty acid (PUFA) in piglets (p < 0.05). Correspondingly, the mRNA expression levels of hepatic ∆5-desaturase (D5D) and ∆6-desaturase (D6D) were higher, and fatty acid synthase (FAS) was lower in piglets from LSO-fed sows when compared with that in the SBO group. In conclusion, LSO supplementation of the maternal diet increases immunoglobulins, modifies the fatty acid composition and affects the gene of D5D and D6D expression of piglets.

High-dose glucocorticoids increases the expression of mineralocorticoid receptor in vascular endothelial cells.

OBJECTIVE: To explore the role of glucocorticoid new mechanism to observe the expression of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) with lipopolysaccharide (LPS) and dexamethasone (Dex) in human umbilical vein endothelial cells (HUVEC). MATERIALS AND METHODS: LPS "injured" endothelial cells with Dex for "treatment", and then detected the expression of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) in the endothelial cells by RT-PCR and immunohistochemistry. RESULTS: With high dose (10-6 mol/L) of Dex to stimulate cell 3h, GRmRNA no significant changes in the expression, 6h began to decrease, 12h peak, 24h recovered nearly the level before stimulation. Using different concentrations of Dex and 100 ng/ml LPS stimulation, HUVEC MRmRNA expression was decreased, and high dose (10-6 mol/L) of Dex to stimulate cell 3h, MRmRNA no significant changes in expression, and GRmRNA The difference is that the expression began to increase 6h, 12h, peaked, 24h rebound near the level before stimulation. Immunohistochemistry results consistent with the RT-PCR. CONCLUSIONS: Large dose of DEX (10-6 mol/l) up-regulated the expression of MR and GR in the reduction of the contrast exactly. GC induced the expression of GR and MR in different changes of stress injury of the body may be a regulatory mechanism, and indicate one new mechanism of glucocorticoid exist.

Anti-osteoporosis activity of red yeast rice extract on ovariectomy-induced bone loss in rats.

Osteoporosis is the most common bone disease, affecting millions of people worldwide and leading to significant morbidity and high costs. Monacolin K, an extract of red yeast rice (RYR, Hongqu), plays important roles in the management of dyslipidemia, coronary heart disease, and diabetes. Our study aimed to investigate the protective effect of monacolin K on ovariectomy-induced bone loss in rats. Fifty female Sprague-Dawley rats were randomly divided into a sham-operated and five ovariectomized (OVX) groups: OVX with vehicle, OVX with fluvastatin, and OVX with RYR extract of three graded doses. Bone mineral density (BMD), biochemical markers, and cell viability were analyzed by dual energy X-ray absorptiometry, enzyme-linked immunosorbent assay, and 3(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Gene expression was evaluated by real-time polymerase chain reaction amplification and western blot. Our results showed that administration of RYR extract markedly increased the bone mineral density in OVX rats. Moreover, RYR extract decreased the levels of bone turnover markers, including osteocalcin and tartrate resistant acid phosphatase activity. The MMT assay revealed that RYR extract treatment significantly improved the osteoblast viabilities in a dose-dependent manner (P < 0.05). At the molecular level, we further demonstrated that RYR extract enhanced the expression of Bmp2 and Bmp4 both at the mRNA and protein levels. Collectively, these data suggested RYR extract could protect against osteoporosis in ovariectomized rats, most likely through activation of BMP2/4 expression.

First Report of Lasiodiplodia theobromae Associated with Stem Canker of Cassia fistula in Guangxi, South China.

Cassia fistula, a member of the Fabaceae, known as the golden shower tree, is native to South Asia. It is now distributed worldwide and is popular as an ornamental plant as well as being used in herbal medicine. In October 2013, symptoms of stem canker were observed on C. fistula in a nursery (108°38' E, 22°87' N) in Nanning, Guangxi, China. The symptoms began as small brown lesions, which enlarged over several months to long, striped, slightly sunken lesions, 1 to 9 cm in width and 16 to 135 cm in length. The conspicuous cankers had vertical cracks outlining the canker and evenly spaced horizontal cracks, eventually resulting in whole plants dying back. The cankers were found on 90% of six-year-old plants in this nursery and were also observed in other plantings. On potato dextrose agar (PDA), isolates with similar morphological characteristics were consistently recovered from symptomatic plant tissues after surface sterilization in 75% ethanol for 30 sec and then in 0.1% mercuric chloride for 2 min. Over 100 conidia were examined from three isolates and were found to be elliptical and hyaline when immature, becoming dark brown, one-septate, and longitudinally striate when mature and ranging from 20 to 31 × 11 to 16 µm (average 25.5 × 13.6 µm). The rDNA internal transcribed spacer (ITS) region of isolate LC-1 was sequenced (GenBank Accession No. KM387285), and it showed 100% identity to Lasiodiplodia theobromae (Pat.) Griffon & Maubl. (GenBank KC964548), confirming the morphological identification (2) as L. theobromae (also known as Botryosphaeria rhodina (Cooke) Arx). A culture of this isolate has been preserved in the Guangxi Academy of Agricultural Sciences fungal collection. The pathogenicity of the isolate was tested on healthy twigs and branches of C. fistula trees in a field setting at Guangxi Agricultural Vocational-Technical College, Nanning, Guangxi, in June and August 2014. For each treatment, five green twigs and five 2-year-old branches were used. Five adjacent needle punctures were made on each branch with a sterilized needle. A mycelial plug was then placed on the wound of each branch and wrapped with Parafilm. Control twigs were treated with sterile PDA plugs. One week later, typical lesions were observed on the inoculated branches, with symptoms becoming more extensive after two weeks, but no symptoms were seen on the controls. Koch's postulates were fulfilled by re-isolation of L. theobromae from diseased branches. L. theobromae is recognized as an important wood pathogen and has been reported to cause cankers, dieback, and fruit and root rots in over 500 different hosts, including perennial fruit and nut trees, vegetable crops, and ornamental plants (2). The fungus has been reported on C. fistula in India since the 1970s (1); however, to our knowledge, this is the first report of L. theobromae infecting C. fistula in China. References: (1) R. S. Mathur. The Coelomycetes of India. Bishen Singh Mahendra Pal Singh, Delhi, India, 1979. (2) J. R. Úrbez-Torres et al. Plant Dis. 92:519, 2008.

Cloning and sequence analysis of the Blumea balsamifera DC farnesyl diphosphate synthase gene.

Blumea balsamifera DC is a member of the Compositae family and is frequently used as traditional Chinese medicine. Blumea balsamifera is rich in monoterpenes, which possess a variety of pharmacological activities, such as antioxidant, anti-bacteria, and anti-viral activities. Farnesyl diphosphate synthase (FPS) is a key enzyme in the biosynthetic pathway of terpenes, playing an important regulatory role in plant growth, such as resistance and secondary metabolism. Based on the conserved oligo amino acid residues of published FPS genes from other higher plant species, a cDNA sequence, designated BbFPS, was isolated from B. balsamifera DC using polymerase chain reaction. The clones were an average of 1.6 kb and contained an open reading frame that predicted a polypeptide of 342 amino acids with 89.07% identity to FPS from other plants. The deduced amino acid sequence was dominated by hydrophobic regions and contained 2 highly conserved DDxxD motifs that are essential for proper functioning of FPS. Phylogenetic analysis indicated that FPS grouped with other composite families. Prediction of secondary structure and subcellular localization suggested that alpha helices made up 70% of the amino acids of the sequence.

Improvement in the carcass traits and meat quality of growing-finishing Rongchang pigs by conjugated linoleic acid through altered gene expression of muscle fiber types.

A total of 160 Rongchang pigs (26.76±1.78 kg) were randomly assigned to 5 dietary treatment groups until their body weight (BW) reached 90 kg. The diets were supplemented with 0, 0.5, 1.0, 1.5, and 2.0% conjugated linoleic acid (CLA). Our results showed that the 1.0 to 2.0% CLA-fed pigs had less back fat deposition when their BW reached 90 kg than the pigs that received less than 1% CLA. During the 30 to 60 kg growing period, 1.0, 1.5, and 2.0% CLA treatments improved pork quality by significantly reducing the pork pH (P<0.01) and color value (P<0.05), but they increased marble scaling (P<0.01). Similarly, the 1.5 and 2.0% CLA-fed pigs had more marble than other pigs when their BW reached 90 kg. Furthermore, CLA significantly affected the expression of muscle fiber-type genes. The 1.5% CLA-fed pigs exhibited the highest mRNA expression of MyHC1 and MyHC2a (P<0.05) at 60 kg BW. At 90 kg BW, the highest expression of MyHC1 and MyHC2a (P<0.05) was found in the 2.0% CLA group. However, MyHC2x was downregulated in the CLA-fed pigs at this time. In addition, CLA supplements did not evidently alter mRNA expression of MyHC2b at all times. These results demonstrate that CLA could affect carcass traits and improve the meat quality of growing-finishing pigs by altering the expression of genes related to muscle growth and development; 1-1.5% CLA was the most appropriate CLA dose.

Antioxidative activity and protective effect of probiotics against high-fat diet-induced sperm damage in rats.

In this study, antioxidant capability and protective effect of probiotics on reproductive damage induced by diet oxidative stress were investigated. Thirty male Sprague-Dawley rats were randomly divided into three groups with 10 rats in each group. The control group consumed a normal standard diet (5% fat, w/w). The other two treatment groups were fed with a high-fat diet (20% fat, w/w), and a high-fat diet supplemented with 2% probiotics (w/w), respectively. At the end of the experimental period, that is, after 6 weeks, rats were killed. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), contents of nitric oxide (NO) free radical and malondialdehyde (MDA) in serum and sperm suspension were examined. Sperm parameters including sperm concentration, viability, motility and DNA integrity were analyzed. The results showed that high-fat diet could induce oxidative stress, shown as significant increases in lipid peroxidation, NO free radical, significant decrease in activities of SOD, GSH-Px, significant reduction in sperm concentration, viability and motility, and damage in sperm DNA (P < 0.05), compared with the control group. These alterations were significantly reversed in the probiotics-supplemented group and had no significant difference in antioxidant capability, lipid peroxidation and sperm parameters compared with the control group. The percentage of sperm with DNA damage was significantly lower than the high-fat diet group and still higher than the control group, which means that probiotics could attenuate sperm damage to some extent. The present results indicated that dietary probiotics had antioxidant activity and the protective effect against sperm damage induced by high-fat diet to some extent.

Observation of superconductivity at 30~46 K in A(x)Fe2Se2(A = Li, Na, Ba, Sr, Ca, Yb, and Eu).

New iron selenide superconductors by intercalating smaller-sized alkali metals (Li, Na) and alkaline earths using high-temperature routes have been pursued ever since the discovery of superconductivity at about 30 K in KFe2Se2, but all have failed so far. Here we demonstrate that a series of superconductors with enhanced T(c) = 30∼46 K can be obtained by intercalating metals, Li, Na, Ba, Sr, Ca, Yb, and Eu in between FeSe layers by the ammonothermal method at room temperature. Analysis on their powder X-ray diffraction patterns reveals that all the main phases can be indexed based on body-centered tetragonal lattices with a∼3.755-3.831 Å while c∼15.99-20.54 Å. Resistivities show the corresponding sharp transitions at 45 K and 39 K for NaFe2Se2 and Ba0.8Fe2Se2, respectively, confirming their bulk superconductivity. These findings provide a new starting point for studying the properties of these superconductors and an effective synthetic route for the exploration of new superconductors as well.

An unusual burn caused by hot argy wormwood leaf water.

An unusual burn case caused by hot wormwood leaf water is discussed. A 29-yr-old woman sustained a 7% seconddegree burn on both buttocks and the left thigh. This case report highlights a rare cause of chemical burn that may become more common with increasing use of this method of traditional Chinese medicine. Measures for preventing this type of burn injury are also presented.

[Effect of rhubarb on intestinal immune associated secretion in healthy mice and in burn mice].

OBJECTIVE: To explore the therapeutic mechanism of rhubarb (sennosides) in protecting intestinal muco-membranous barrier by observing the change of intestinal immune associated secretion (IIAS) in mice before and after burn and the enhancing effect of rhubarb on it in healthy and in burn mice. METHODS: Bal b/c mice were divided into 4 groups. Group A (n = 8), untreated healthy mice; Group B (n = 11), healthy mice treated with 10% rhubarb decoction 12 ml/kg, once every 6 hrs; Group C (n = 7), the mice with 30% back full-thickness burn and no treatment was given; Group D (n = 9), the mice with 30% back full-thickness burn and treated with 10% rhubarb decoction 12 ml/kg, once every 6 hrs. The animals were killed 24 hrs after burn, the intestinal juice was collected after intestinal lavage, and centrifuged for determination of IgA, total protein, C3 and high density lipoprotein. RESULTS: IgA content in intestinal juice of Group A, B, C and D were 93.5 +/- 13.7 mg/L, 150.8 +/- 44.6 mg/L, 43.4 +/- 21.5 mg/L and 59.8 +/- 19.3 mg/L respectively, suggesting that it was significantly reduced by burn (P < 0.05), while rhubarb decoction could increase it in either healthy or burn mice (P < 0.05). The other immune associated substance, such as total protein, C3 and high density lipoprotein in intestinal juice were also increased significantly after rhubarb decoction treatment. CONCLUSION: Rhubarb could increase the reduced intestinal juice IgA content in mice caused by burn, it may be an important mechanism of rhubarb in protecting muco-membranous barrier.

Na(+)-Ca2+ exchange, myoplasmic Ca2+ concentration, and contraction of arterial smooth muscle.

Na(+)-Ca2+ exchange is proposed to be an important regulator of myoplasmic intracellular Ca2+ concentration ([Ca2+]i) and contraction in vascular smooth muscle. We investigated the role of Na(+)-Ca2+ exchange in regulating [Ca2+]i in swine carotid arterial tissues that were loaded with aequorin to allow simultaneous measurement of [Ca2+]i and force. Reversal of Na(+)-Ca2+ exchange, by reduction of extracellular Na+ concentration ([Na+]o) to 1.2 mM, induced a large increase in aequorin-estimated [Ca2+]i and a low [Ca2+]i sensitivity. The contraction induced by 1.2 mM [Na+]o was partially caused by depolarization and opening of L-type Ca2+ channels because 10 microM diltiazem partially attenuated the 1.2 mM [Na+]o-induced increases in [Ca2+]i. High dose ouabain (10 microM), a putative endogenous Na+,K(+)-ATPase inhibitor, increased both [Ca2+]i and force. However, the increases in [Ca2+]i and force were mostly blocked by 10 microM phentolamine, suggesting the predominant effect of ouabain was to increase norepinephrine release from nerve terminals. In the presence of 10 microM phentolamine, 10 microM ouabain slightly accentuated 1 microM histamine-induced increases in [Ca2+]i and force. The ouabain dose necessary to induce contraction in the absence of phentolamine was significantly less than the ouabain dose necessary to accentuate histamine-induced contractions in the presence of phentolamine. These results suggest that Na(+)-Ca2+ exchange exists in swine arterial smooth muscle. These data also suggest that ouabain (which should increase [Na+]i and inhibit Na(+)-Ca2+ exchange) primarily enhances contractile function in the swine carotid artery by releasing catecholamines from nerve terminals; direct action of Na+,K(+)-ATPase inhibitors on smooth muscle appears to occur only with very high doses.

[Effects of Apocynum hendersonii (Hook. f.) Woodson on cardiac electric and mechanical activity].

Calcium antagonist-like effect of Apocynum hendersonii on myocardiac preparations was observed in the present experiments. The action potential duration and contractility were decreased. Automatic or exciting activity in partially depolarized fibers was considerably inhibited or concealed. Observation in vivo showed that pacemaking in SA node and conducting in AV node area were inhibited.

Cardiovascular effects and modulation of noradrenergic neurotransmission following central and peripheral administration of neuropeptide Y.

Experiments have been conducted to evaluate the effect of neuropeptide Y (NPY) administered at three distinct levels of the nervous system: 1) the posterior hypothalamic nucleus, 2) the spinal cord, and 3) the vascular noradrenergic neuroeffector junction. It was observed that NPY produced varying cardiovascular effects at these three distinct sites of the nervous system. Microinjections into the posterior hypothalamic nucleus resulted in an increase in blood pressure, which was reduced by prior microinjection of a muscarinic or H1-histamine antagonist but not an H2-histamine antagonist. In addition to the involvement of histaminergic and cholinergic pathways, the pressor effect of NPY appears to result from an increase in sympathetic outflow. NPY was also seen to decrease the potassium-induced release of norepinephrine (NE) from slices obtained from the posterior hypothalamic nucleus. In contrast to what was observed in the hypothalamus, the intrathecal injection of NPY at a level of T4 or T10 in anesthetized or T10 in unanesthetized rats resulted in a depressor effect as well as a decrease in heart rate. Both an alpha 2- and beta-adrenoceptor antagonist reduced the NPY effect. The depressor effect of intrathecal NPY was attenuated in rats pretreated with reserpine as well as in Spontaneously Hypertensive rats (SHR). These data suggest that the effects of NPY are closely associated with sympathetic preganglionic neurons in the spinal cord. At the vascular noradrenergic neuroeffector junction, NPY decreased the nerve stimulation-induced release of NE while potentiating the contractile response. Moreover, NPY potentiated the increase in perfusion pressure of the perfused mesenteric arterial bed in response to angiotensin, vasopressin, or phenylephrine.(ABSTRACT TRUNCATED AT 250 WORDS)