Ghrelin differentially modulates the GH secretory response to GHRH between the fed and fasted states in sheep

The effect of energy balance on the growth hormone (GH) secretory responsiveness to growth hormone-releasing hormone (GHRH) has not been determined in ruminant animals. Therefore, we examined the effects of intravenous injections of 0, 3.3, and 6.6 μg ghrelin/kg body weight (BW), with and without GHRH at 0.25 μg/kg BW, on GH secretory responsiveness in both the fed and fasted sheep. The injections were carried out at 48 h (Fasting state) and 3 h (Satiety state) after feeding. Blood samples were taken every 10 minutes, from 30 minutes before to 120 minutes after the injection. Low (3.3 μg/kg BW) and high (6.6 μg/kg BW) doses of ghrelin stimulated GH secretion significantly (P < .05) greater in the Satiety state than in the Fasting state. Growth hormone-releasing hormone plus both doses of ghrelin stimulated GH secretion significantly (P < .05) greater in the Satiety state than in the Fasting state. Ghrelin and GHRH exerted a synergistic effect in the Satiety state, but not in the Fasting state. Plasma ghrelin levels were maintained significantly (P < .05) greater in the Fasting state than in the Satiety state except the temporal increases after ghrelin administration. Plasma free fatty acid (FFA) concentrations were significantly (P < .01) greater in the Fasting state than in the Satiety state. In conclusion, the present study has demonstrated for the first time that ghrelin differentially modulates GH secretory response to GHRH according to feeding states in ruminant animals.     

Impaired Development of Somatotropes, Lactotropes and Thyrotropes in Growth-Retarded (grt) Mice

Congenitally primary hypothyroid growth-retarded (grt) mice exhibit a characteristic growth pause followed by delayed onset of pubertal growth. We characterized the developmental pattern of somatotropes, lactotropes and thyrotropes in the anterior pituitary, as well as plasma levels of their secretory hormones, in grt mice. Compared with normal mice, the weight of grt pituitary gland was similar at 8 weeks of age but significantly heavier after 12 weeks of age. Compared with normal mice, there were significantly fewer somatotropes in the grt pituitary until 8 weeks of age, but the number gradually increased up to 48 weeks. The number of lactotropes in grt mice was consistently lower than that in normal mice from 2 through 48 weeks, whereas the number of thyrotropes in the grt pituitary was consistently higher than in the normal pituitary. Thyrotropes in the grt pituitary exhibited hypertrophy and hyperplasia with less intensive thyroid-stimulating hormone (TSH) immunoreactivity than normal thyrotropes. In normal mice, the sum of the relative proportions of these cells plateaued at 8 weeks, where it remained up to 48 weeks of age. In grt mice, these proportions almost reached normal levels at 12 weeks of age but gradually declined after 24 weeks. Plasma growth hormone concentrations did not differ between grt and normal mice until 24 weeks of age. Compared with normal mice, grt mice exhibited significantly lower plasma prolactin and thyroxine levels but higher TSH levels. These findings indicate that development of somatotropes, lactotropes and thyrotropes in grt mice is impaired, being followed by altered hormone secretion.     

Incidence of Error in Oestrus Detection Based on Secondary Oestrus Signs in a 24-h Tie-Stalled Dairy Herd with Low Fertility

Oestrus detection error and conception rates after AI based only on secondary oestrus signs were evaluated in a high yielding, 24-h tie-stalled dairy herd with low fertility, using milk progesterone profiles. Oestrus detection was based on the secondary oestrus signs such as restlessness, swelling, congestion of vulva and clear mucus discharge. Sixty eight AI conducted after observing the secondary oestrus signs in 44 animals were included in the study. Of the 68 AI, 53 (77.9%) were conducted in the follicular phase, and 13 (19.1%) and 2 (2.9%) were carried out in the luteal phase and during pregnancy, respectively. The overall error in oestrus detection based on milk progesterone profiles was 22.1%. The oestrus detection error did not differ significantly among different secondary oestrus signs. None of the AI conducted in the luteal phase resulted in conception, whereas 20.8% of AI conducted in the follicular phase resulted in conception. No significant difference in the conception rates among the groups of cows with different secondary oestrus signs was shown. The high incidence of oestrus detection error in this study might have been caused by the detection of cows in oestrus based only on secondary oestrus signs due to the confinement of animals. In conclusion, there was a high incidence of heat detection error in the 24-h tie-stalled dairy herd and oestrus detection based only on secondary oestrus signs resulted in low conception rate.     

Generation of adrenergic and cholinergic potentials in sympathetic ganglion cells

Norepinephrine elicited a hyperpolarizing response, and acetylcholine (during nicotinic blockade) elicited a depolarizing one. Both responses showed no increase in membrane conductance. The norepinephrine response was suppressed by initial depolarization; the acetylcholine response (frog cells); by hyperpolarization. These neurotransmitters apparently can activate electrogenic mechanisms which do not involve movement of ions down their electrochemical gradients.     

日本柳杉髓心方材高频真空干燥试验

该文对日本人工林柳杉髓心方材进行系列高频真空干燥试验,掌握不同高频真空干燥条件下柳杉髓心方材的干燥特性并对干燥缺陷进行分析.结果表明,柳杉髓心方材虽难干燥,但在高频真空干燥前对木材进行合理的处理,如蒸汽和过热蒸汽预处理、沿木材长度方向制作一定深度和宽度的切口等,可有效地提高干燥质量,尤其是可减少开裂的产生.     

Nosological study of Borna disease virus infection in race horses.

To investigate the prevalence of diseases in the Borna disease virus (BDV) antibody positive race horses, we undertook seroepidemiological studies of BDV infection on 125 culled race horses in Hokkaido, Japan. The serological study disclosed the presence of antibodies only to BDV-p40 or -p24 in 19.2% (24/125) and 3.2% (4/125) of culled horses, respectively. Antibodies to both BDV-p40 and -p24 were found in 24.0% (30/125) of these horses. Of particular note was the finding that locomotorium disorders were detectable at a significantly higher rate in BDV antibody positive horses than that in the seronegative horses. These results imply that BDV infection may possibly contribute to an increase in the incidence rate of locomotorium disorders in race horses.     

Contamination of Radio active Substances in Grapes

We have studied the quantitative analysis of potassium in agricultural materials by measuring the radioactivity of K4o by means of Radiation Counter since 1951. When the fundamental experiment was almost over and we were to begin the applications in fertilizers and crops, we found unexpectedly in May 1954, rain containing fission products presumably carried from H-bomb explosion test at Bikini. Temporarily abstaining from the experiment, we surveyed the degree of contamination of radioactive substances in crops, especially grapes, which are the main horticultural crop in this prefecture. Here, we explain the experimental data of the radioactivity in the grapes and the relations between the contamination of the artificial radioactivity and the potassium content in them.     

Nitrogen-Fixing microorganisms in paddy soils VII.

In the previous paper (1) it has been repored that the the amount of nitrogen fixed was very much increased when Rhodopseudomonas capsulatus was cultured with Azotobacter vinelandii probably due to their symbiotic relationship.