Gastrointestinal motility modulation by stress is associated with reduced smooth muscle contraction through specific transient receptor potential channel

Excessive stress response causes disability in social life. There are many diseases caused by stress, such as gastrointestinal motility disorders, depression, eating disorders, and cardiovascular diseases. Transient receptor potential (TRP) channels underlie non-selective cation currents and are downstream effectors of G protein-coupled receptors. Ca²⁺ influx is important for smooth muscle contraction, which is responsible for gastrointestinal motility. Little is known about the possible involvement of TRP channels in the gastrointestinal motility disorders due to stress. The purpose of this study was to measure the changes in gastrointestinal motility caused by stress and to elucidate the mechanism of these changes. The stress model used the water immersion restraint stress. Gastrointestinal motility, especially the ileum, was recorded responses to electric field stimulation (EFS) by isometric transducer. EFS-induced contraction was significantly reduced in the ileum of stressed mouse. Even under the conditions treated with atropine, EFS-induced contraction was significantly reduced in the ileum of stressed mouse. In addition, carbachol-induced, neurokinin A-induced, and substance P-induced contractions were all significantly reduced in the ileum of stressed mouse. Furthermore, the expression of TRPC3 was decreased in the ileum of stressed mouse. These results suggest that the gastrointestinal motility disorders due to stress is associated with specific non-selective cation channel.     

Keratometry in normal cats: a cross-sectional study in Japan using an automated handheld keratometer

Keratometry was performed in 73 domestic cats of varied signalment in Japan using an automated handheld keratometer. The mean corneal curvature radius was significantly lower for cats younger than 1 year than for those older than 2 years (8.04 mm vs. 8.80−8.99 mm, P<0.01). The radius was significantly greater in males than in females among the cats older than 11 years (9.22 mm vs. 8.84 mm, P=0.01), while the age distributions of the males and females were similar. Corneal astigmatism did not significantly differ across the gender and age groups. The predictability of the corneal curvature and astigmatism was approximately 41−43% and less than 3%, respectively, as a function of age and bodyweight. The results highlighted some age- and sex-related keratometric variations in domestic cats in Japan.     

OSTEORADIONECROSIS AND RADIATION INDUCED BONE TUMORS FOLLOWING ORTHOVOLTAGE RADIATION THERAPY IN DOGS

Osteoradionecrosis and radiation-induced bone tumors are rare complications of radiation therapy. Little information regarding these complications is available in veterinary medicine. We characterized these complications and investigated risk factors in 119 dogs (122 sites) that received definitive orthovoltage radiation therapy to appendicular sites. Long-term survival was expected in all dogs. The complications of interest were osteoradionecrosis and secondary bone tumor, evaluated radiographically, histopathologically, or both. Complication rates were estimated using the Kaplan–Meier product-limit method, and Fisher's exact test or chi-square test was used to compare the complication rate. The median survival time was 1405 days, with median follow-up duration of 657 days. There were 10 radiation-induced bone tumors and five radiation-induced fractures, with two dogs developing both, for an overall complication rate of 11%. The latent period ranged from 1.2 to 6.4 years for osteoradionecrosis and from 2.6 to 8.7 years for radiation-induced bone tumor. Complications were significantly higher in the humerus ( P <0.0001), and in dogs younger than 7 years ( P =0.014). Similar assessment of complications in dogs irradiated with megavoltage photons or electrons are needed.     

Annual changes in the hatching period of the dominant cohort of larval and juvenile ayu Plecoglossus altivelis altivelis in the Shimanto Estuary and adjacent coastal waters during 1986–2001

ABSTRACT:   Larval and juvenile ayu from seven year-groups (1986, 1987, 1992, 1995, 1996, 1999 and 2000) were collected in the Shimanto Estuary and adjacent coastal waters. The present study focuses on the variation among year-groups in the hatching period estimated by age determination using the otolith. The hatching period of the dominant cohorts in the 1986, 1987 and 1992 year-groups occurred from late October to mid-November. A delay of the hatching period of the dominant cohort was observed from the 1995 year-group, which occurred in late November to early December, and the dominant periods in the 1996, 1999 and 2000 year-groups were observed from early to late December. It appears that the delay of the hatching period of dominant cohorts was not due to a delay of spawning, but a high mortality of early hatched larvae. The water temperature in autumn in the coastal waters adjacent to the Shimanto River has tended to rise over the past 20 years and this trend was especially notable in the late 1990s. The delay in the hatching period of the dominant cohort observed from the 1995 year-group was likely to be related to the rise in seawater temperatures in autumn.     

Computed tomographic images of discospondylitis in a calf

A 2-month-old male Japanese Black calf was presented with a 30-day history of progressive ataxia. Antemortem examination using computed tomography (CT) revealed narrowing of the disc spaces due to destruction of intervertebral structures between the first and second thoracic vertebrae and between the second and third thoracic vertebrae. Osteolysis was evident as irregular hypoattenuating lesions within the opposing end plates of the first, second and third thoracic vertebrae. Pseudomonas aeruginosa was detected as the causative bacteria, and discospondylitis was diagnosed. To the best of our knowledge, this is the first bovine case report describing the application of CT for the diagnosis of discospondylitis.     

Effects of central administration of glucagon on feed intake and endocrine responses in sheep

This study was conducted to investigate effects of glucagon intracerebroventricularly administered on feed intake and endocrine changes in sheep. Four male sheep (48–55 kg BW) were used. The animals were acclimatized to be fed alfalfa hay cubes at 12.00 hour. Human glucagon (40 and 80 µg/0.5 mL) was injected into the lateral ventricle at 12.00 hour. Blood samples were taken every 10 min from 30 min before to 180 min after the glucagon injection. Soon after the injection, the animals were given alfalfa hay cubes, and the amounts of the feed eaten within 2 h were measured. Feed intakes were significantly (P < 0.05) suppressed by 80 µg of glucagon. Plasma glucose levels in control animals were gradually decreased after the feeding, whilst those in glucagon‐treated animals were temporarily elevated just after the feeding and then kept higher than control levels. Plasma insulin was abruptly elevated after the feeding and was maintained at higher levels than before the feeding in all treatments. Plasma NEFA concentrations were decreased after the feeding in all treatments. A tendency of increase in plasma cortisol levels occurred in glucagon‐injected animals. The present study provides the first evidence that glucagon directly acts on the brain, then inhibiting feeding behavior and inducing endocrine responses in ruminants.     

Changes in fertility of rainbow trout eggs retained in coelom

ABSTRACT:    Effects of prolonged retention time of ovulated eggs in the parental coelom on fertilization success were studied in rainbow trout Oncorhynchus mykiss using cryopreserved sperm with a uniform fertilizing ability. Proportions of successful fertilization, eyed eggs and hatched alevins were examined at different time periods up to a retention time of 14 days beyond the ordinary stripping time, and were compared with eggs incubated in artificial coelomic fluids (ACF). Eggs that were retained longer in the coelom showed gradual decreases in all the proportions of successful fertilization, eyed eggs and hatched alevins. The progress of cleavage after fertilization slowed with prolonged retention times. Eggs incubated in ACF lost their fertilizing ability much sooner than those retained in the coelom. The hatching rate of eggs retained for 2 weeks in coelom was 36%, while it was 1% in those eggs incubated for 4 days in ACF. Thus, eggs retained in the coelom showed higher fertilization success than those incubated in ACF.     

Species composition and seasonal occurrence of fish larvae and juveniles in the Shimanto Estuary, Japan

ABSTRACT: To clarify the characteristics of the larval and juvenile fish community in a Japanese estuary, monthly collections were conducted in the shallow waters of the Shimanto Estuary, Japan from July 1985 to June 1987. A total of 49 101 fishes of more than 100 species from 44 families were sampled over the 2-year period. Numerically, Gerres equulus was most common, accounting for 20.02% of the total abundance. Rhyncopelates oxyrhynchus was ranked second, followed by Acanthopagrus latus , Acanthogobius flavimanus , Mugil cephalus cephalus , Parioglossus dotui , and Acanthopagrus schlegeli . Thus, fishes observed in the estuary were mostly marine species that spawn in the sea. The majority of these fish first appeared within the estuary at late postlarval and/or early juvenile stages. Based on their utilization of the shallow waters in the estuary, the majority of species could be categorized as residents. In the Shimanto Estuary, shallow waters are studded with shelters, especially eelgrass beds, which serve as important nursery grounds for coastal and euryhaline fishes.     

USE OF FORCE PLATE ANALYSIS TO EVALUATE THE EFFICACY OF EXTERNAL BEAM RADIATION TO ALLEVIATE OSTEOSARCOMA PAIN

A standard of therapy for osteosarcoma includes amputation with or without adjuvant chemotherapy. There is a subset of dogs with osteosarcoma that are unsuitable for amputation. We evaluated kinetic variables in dogs with appendicular osteosarcoma treated with a single 8 Gy dose of radiation. Eighteen pet dogs with appendicular osteosarcoma received one 8 Gy fraction of palliative radiation on day 0. Force plate measurements and clinical assessments were made on days 0, 7, 14, and 21. Peak vertical forces ( F _z) were recorded for each limb and a symmetric index (SI) was calculated. There were no significant changes in kinetic parameters after one 8 Gy dose of radiation therapy. Nine of these 18 dogs exhibited increased limb function at day 21 based on force plate analysis. Significant factors affecting F _z included gender and tumor location. There was a significant correlation between F _z and response to therapy based on SI at day 21. SI seems to be useful to objectively assess response in this mixed population of dogs. One 8 Gy fraction of radiation therapy alone did not reduce lameness associated with appendicular osteosarcoma, but a subset of dogs did have improved limb function after a single dose.