Developmental change in the gene expression of transient receptor potential melastatin channel 3 (TRPM3) in murine lacrimal gland.

Transient receptor potential (TRP) channels are cation channels with ubiquitous expression. Various TRP channels are functionally active at the ocular surface and are involved in tear secretion and multiple inflammatory processes. So far, the impact of TRP channels regarding the development of the lacrimal gland (LG) is unclear. While investigating TRP channels in the LG, the TRPM3 channel presented itself as a promising candidate to play a role in the development and functioning of the LG. Therefore, Trpm3 expression was analyzed in different embryonic and postembryonic LGs. Thus, gene expression of TRPM channels including Trpm2, Trpm3, Trpm4 and Trpm6 was analyzed by quantitative RT-PCR in murine LGs at different developmental stages. Localization of TRPM3 in LGs was examined by immunohistochemistry. Primary LG epithelial cells (LGEC) and mesenchymal cells (MC) from newborn mice were cultured (either separately or collectively) for three days, and Trpm3 expression was analyzed in LGEC and MC. As a result, gene expression of Trpm2, Trpm4 and Trpm6 showed no significant difference in LGs in the different stages of development. However, Trpm3 gene expression was significantly higher in the embryonic stage than in the postnatal stage with the peak at E18. Postnatal, Trpm3 expression significantly decreased up to 28-fold until two years of age. Immunohistochemistry for TRPM3 revealed apical membranous expression in the excretory ducts, as well as in the acini of up to P7 old mice. Trpm3 expression in LGEC were significantly higher than that of MC. Our results indicate that Trpm3 expression in murine LG is age-dependent and peaks at age E18. Its expression is localized in the apical membrane of the glandular epithelium. However, its functional role still requires additional study in the LG.

Maintenance nitrogen requirements of adult female ostriches (Struthio camelus).

Successful ostrich farming requires knowledge of the nutritional needs of the birds. While much information is available on the nutritional value of various feed ingredients fed to ostriches, there is little known about their specific nutrient requirements. In this study, we measured the maintenance nitrogen requirements (MNR) of ostriches by nitrogen balance. We predict, based on the previous analysis of nitrogen requirements of various species of birds, that ostriches would have a MNR of 13.6-19.1 g N/day and a total endogenous nitrogen loss (TENL) of 2.8-5.1 g N/day. Three adult female ostriches were fed five pelleted diets containing 0.6-2.3% N [4-14.6% crude protein (CP)], 17.5 kJ/g gross energy (11.4 kJ/g ME) and 30% neutral detergent fibre. Each dietary trial consisted of a 10-day adaptation period, followed by a 5-day total excreta collection period. Body mass (109 ± 3 kg) and metabolizable energy intake (20.5 ± 0.7 MJ/day) were unaffected by dietary nitrogen levels. After correcting for excreta nitrogen losses during drying, MNR was calculated to be 481 mg N/kg(0.75) /day or 16.2 g N/day (100 g CP/day), and TENL as 310 mg N/kg(0.75) /day or 10.5 g N/day. Failure to correct for the 10.9 ± 4.1% average N losses during drying would underpredict the 'true' MNR by 35% and TENL by 46%. Our estimate for MNR of ostriches predicts a dietary requirement of 6.7% protein. Our estimate of TENL was nearly twice that predicted, possibly reflecting the high fibre content of their diet.

Use of multislice helical computed tomography cholangiography in the diagnosis of biliary disease.

A recent advance in computed tomography (CT) technology, multislice helical CT, has enabled production of clearer three-dimensional (3D) images and has drawn interest. We report the usefulness of CT cholangiography using a multislice helical CT scanner for the diagnosis and preoperative imaging of the biliary duct in a case of peculiarly shaped gallbladder with cholecystitis. A 34-year-old woman admitted to our hospital presented with chronic hypochondralgia. A CT scan showed that the gallbladder was normal without wall thickening or stones. However, there appeared to be a tumor, containing a stone approximately 1 cm in diameter, attached under the gallbladder in front of the right kidney and extending up to its lower level. Magnetic resonance cholangiography also depicted a normal gallbladder without wall thickening or stones. Hence, gallbladder stones were not diagnosed by previously the mentioned investigations. In contrast, a 3D image produced by multislice helical CT cholangiography was very clear. From the bottom of the gallbladder, a narrow canal continued to a stone. We diagnosed that the wall of the lower part of the long gallbladder had become thick and elongated because of chronic cholecystitis caused by a gallbladder stone, and laparoscopic cholecystectomy was performed. Macroscopically, the resected gallbladder showed an extremely thickened wall from the lower body to the fundus, in which a stone was located in the center. Multislice helical CT cholangiography has the potential to become one of the most significant examinations for diagnosis and anatomical analysis of biliary disease prior to laparoscopic cholecystectomy.

Is preoperative portal vein embolization effective in improving prognosis after major hepatic resection in patients with advanced-stage hepatocellular carcinoma?

BACKGROUND: The impact of the use of preoperative portal vein embolization (PVE) on long-term survival after surgery was evaluated by retrospective analysis of prognostic factors in patients with advanced-stage hepatocellular carcinoma (HCC) who had undergone hepatic resection with or without PVE. METHODS: The portal embolization group (Group P) consisted of 26 patients who had undergone major hepatectomy (more extensive than right hepatectomy) with PVE, and the nonembolized group (Group N) consisted of 43 patients who had undergone major hepatectomy without PVE. All patients were diagnosed with advanced HCC graded as Stage III or IV according to the International Union Against Cancer TNM classification system. Patient survival rates, recurrence rates, and recurrence sites after surgery in the two groups were evaluated and compared. RESULTS: The 1-year, 3-year, and 5-year cumulative disease specific survival rates in patients with TNM Stage III HCC, respectively, were 96.0%, 64.4%, and 52.7% in Group N and 92.9%, 57.1%, and 45.7% in Group P, whereas the corresponding values in patients with Stage IV HCC were 53.5%, 40.1%, and 26.8% in Group N and 63.5%, 50.8%, and 19.1% in Group P. There were no statistically significant differences in survival rates between Group P and Group N. Multivariate analysis showed that PVE was not a significant prognostic factor. The 1-year, 3-year, and 5-year cumulative recurrence rates for patients with both stages of disease combined were 44.1%, 80.2%, and 86.8% in Group N, respectively, and 39.9%, 72.2%, and 72.2% in Group P, respectively, with no statistically significant differences between the two groups. To date, 35 patients in Group N and 16 patients in Group P have had tumor recurrences in the liver remnant; of these, 27 patients in Group N and 12 patients in Group P had multiple recurrence foci in the liver remnant. No significant difference was seen between the two groups; however, 10 of 16 patients in Group P (62.5%) had remote organ metastasis in addition to recurrence in the liver remnant compared with only 6 of 35 patients in Group N (17.1%): This difference was significant statistically (P = 0.012). CONCLUSIONS: PVE during major hepatic resection neither improves nor worsens long-term prognosis but allows resection in a patient group that, otherwise, is considered as unresectable. Remote metastasis involving the lung, bone, or stomach was seen more frequently postoperatively in Group P compared with Group N, raising a possibly important issue regarding the use of this approach for the treatment of patients with hepatic malignancies, especially HCC.

Retrohepatic vena cava replacement of hepatic malignancies without using total hepatic vascular exclusion or extracorporeal bypass.

Total hepatic vascular exclusion and venovenous bypass are frequently used surgical procedures when concomitant resection of the inferior vena cava is required during surgery of liver cancer involving the retrohepatic inferior vena cava close to the hepatic veins. However, the duration of total hepatic vascular exclusion is limited due to the risk of hepatic ischemia. Three patients presented with severely compressed inferior vena cava and/or hepatic veins due to liver cancer. The surgical procedure involved initial taping of the inferior vena cava just below the hepatic veins by extrahepatic division and taping of the hepatic veins. After taping the inferior vena cava, hepatectomy with caval resection was performed by simply clamping the retrohepatic inferior vena cava, without the need for total hepatic vascular exclusion or venovenous bypass. In all patients the retrohepatic inferior vena cava were safely replaced with a prosthetic graft under stable hemodynamics. Duration of the inferior vena cava clamping was 31, 66, 75 minutes, respectively. No graft-related complications occurred, but 2 of the 3 patients showed temporal renal dysfunction associated with renal congestion postoperatively. The surgical procedure described herein is effective for the treatment of retrohepatic inferior vena cava in some patients. However, when the case is complicated by chronic nephropathy or simultaneous nephrectomy is required, venovenous bypass should be performed.

Chronic methamphetamine administration inhibits cerebral ischemia-induced hyperactivity in Mongolian gerbils.

The effect of single and chronic methamphetamine (MAP) administration on ischemia-induced hyperactivity was investigated and the mechanism of ischemia-induced hyperactivity was discussed. Ischemia-induced hyperactivity was recognized 3 h after ischemia. However, ischemia-induced hyperactivity at 1 day after ischemia was inhibited when MAP, in a dose of 10 mg/kg, was administered for 7 days and withdrawn for 7 days. It was reported that MAP treatment caused an irreversible decrease in the number of dopamine (DA) uptake sites. In addition to this, monoamine oxidase and the uptake of DA into the nerve terminals are disturbed by cerebral ischemia. Therefore, a lot of DA release happened during and immediately after ischemia, and a marked down-regulation of DA receptor occurred 24 h after ischemia in MAP-injected group. It is conceivable that the DA receptor, especially the presynaptic DA uptake site, is related to the occurrence of ischemia-induced hyperactivity. Further studies appear to be necessary to clarify acceptor susceptibility when neurotransmitters are normalized after transient ischemia.

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1999)].

From October 1999 to September 2000, we collected the specimen from 430 patients with lower respiratory tract infections in 17 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various antibacterial agents and antibiotics and patients' characteristics. Of 515 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 506 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 101, Haemophilus influenzae 104, Pseudomonas aeruginosa (non-mucoid) 58, P. aeruginosa (mucoid) 11, Moraxella subgenus Branhamella catarrhalis 41, Klebsiella pneumoniae 18, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or above of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 57.7%. Vancomycin and arbekacin showed the most potent activities against MRSA without detection of ABK-resistant strain (MIC: 64 micrograms/ml) and decrease of VCM-sensitive strains those were found in 1998. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) decreased to 34.7% from 46.0% in 1998. The frequency of PRSP was 3.0%, being the least number after 1991. Carbapenems showed strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 101 strains with MIC of 0.063 microgram/ml. Generally, all drugs showed strong activities against H. influenzae with MIC80s of 4 micrograms/ml or below. MICs of ofloxacin ranged between 0.063 microgram/ml and 4 micrograms/ml in 1998, however, those were 0.125 microgram/ml or below in all H. influenzae in 1999 showing the strongest activity. Tobramycin and ciprofloxacin showed strong activities against P. aeruginosa (both mucoid and non-mucoid) with MIC80s of 1 microgram/ml. Number of isolated P. aeruginosa (mucoid) was little as 11, however, the susceptibilities to all drugs were better than P. aeruginosa (non-mucoid). K. pneumoniae showed good susceptibilities to all drugs except for ampicillin with decreasing of low-sensitive strains compared to those detected in 1998. Also, all drugs generally showed strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or below. The drug which showed the strongest activity was imipenem inhibiting all 41 strains with MIC of 0.063 microgram/ml. On the patients' characteristics, the number of patients aged 80 years or older who had been increased was decreased in 1999 in the distribution by age. The percentage of the elderly patients aged 70 years or older was 47.0%, which occupied almost a half number of the total patients as in the last year. As for the incidence by disease, bacterial pneumonia and chronic bronchitis were the highest. They were noted in 37.9% and 30.5% of the patients, respectively. In 1999, bronchial asthma was frequently observed as compared in recent years. It was noted in about 10% of the patients which is the same % as in bronchiectasis. We examined the number of strains from these patients with infections before and after administration of antibiotics. In patients with bacterial pneumonia, the number of isolated strains was almost the same between those before and after administration. However, in patients with chronic bronchitis, the number of strains remarkably decreased to less than the half of the total after administration of antibiotics in the last year, but it decreased to 2/3 of the total in 1999. On the administration of antibiotics and isolated bacteria by the day of administration, the bacteria which were isolated more before administration were H. influenzae in 28.4%, S. pneumoniae in 25.7%, M. (B.) catarrhalis in 12.0% and S. aureus in 10.6%. The frequency of S. aureus after administration over 15 days was almost the same as that before administration, but the frequency of P. aeruginosa (both mucoid and non-mucoid) was 36.8% which was higher than that before administration. The frequency of isolated S. pneumoniae was decreased after administration and none of them was isolated after completion of administration. However, that of H. influenzae was decreased to 7.1% after administration within 3 days, and many H. influenzae were isolated after completion of administration as 21.4%.

Effects of caecal ligation and colostomy on water intake and excretion in chickens.

1. The effect of caecal ligation and colostomy on water intake and excretion were examined in chickens fed a low-protein diet or a low-protein diet supplemented with urea. 2. When fed a low-protein diet, the water intake and the ratio of water intake to food intake were increased by colostomy (P < 0.05) but not changed further by caecal ligation of colostomised chickens. 3. When fed a low-protein diet supplemented with urea, the amount of water intake and the ratio of water intake to food intake were not changed by either treatment. 4. Total water excretion was much higher in the colostomised plus caeca-ligated chickens than in other 3 groups fed both types of diet (P < 0.05). 5. The amount of faecal water excretion was increased by cecal ligation in colostomised chickens fed either diet (P < 0.01). 6. No effect of any treatment on water balance was observed in chickens fed either diet. 7. It is concluded that the lower intestine plays a useful role in the water economy of chickens fed a low-protein diet or a low-protein diet supplemented with urea.

Hepatocarcinogenesis inhibition by caffeine in ACI rats treated with 2-acetylaminofluorene.

The inhibitory effects of caffeine have been demonstrated on the development of various organs in animals. The purpose of the present study was to examine the inhibitory effect of caffeine on hepatocarcinogenesis and to determine the responsive dose of caffeine on hepatocarcinogenesis in young male ACI rats. Animals given a diet containing 2-acetylaminofluorene (2-AAF) for 12 weeks and then a basal diet and tap water containing caffeine for 18 weeks showed statistically significant decreases in the incidence, multiplicity (the number of hepatic tumors per rat) and histological grade compared with rats fed a diet containing carcinogen for 12 weeks followed by tap water alone. Dose-dependent inhibition of hepatocarcinogenesis by caffeine was also seen. The inhibitory effect of caffeine on hepatocarcinogenesis in rats was found when caffeine was administered during the initiation phase.

Insulin and somatostatin releasing islet cell tumor caused hypoglycemia.

We report a hypoglycemic case with normal insulin levels, which was caused by an islet cell tumor that was releasing insulin and somatostatin. A fasting test suggested the over secretion of insulin. Moreover, this hypoglycemia was enhanced by the inhibitory effect of somatostatin on the secretion of insulin counter-regulatory hormones, such as glucagon, in addition to the autonomous secretion of insulin from the tumor. In cases of hypoglycemia with apparently normal insulin levels, the measurement of somatostatin and various provocative tests are recommended. Arterial stimulation venous sampling (ASVS) was useful to detect the location of this functioning islet cell tumor.

Duodenal somatostatinoma and erythrocytosis in a patient with von Hippel-Lindau disease type 2A.

A female with von Hippel-Lindau (VHL) disease type 2A first presented with erythrocytosis at the age of 9 years. This patient revealed multiple paragangliomas at age 22. After the removal of tumors, a retinal hemangioblastoma developed. Our diagnosis of VHL disease type 2A was confirmed. Moreover, systemic examination showed a duodenal somatostatinoma. Frequent and long-term monitoring is important for patients with pheochromocytomas or paragangliomas, and a screening for VHL disease and other hereditary cancer syndromes is recommended. Recognition of neuroendocrine tumors as a manifestation of VHL disease permits earlier diagnosis and improves prognosis.

Apoptosis after butyrate-induced differentiation in retinoblastoma cell line Y-79.

PURPOSE: To study the fate of Y-79 human retinoblastoma cells after induction of differentiation. METHODS: Y-79 cells were cultured in a synthetic medium and were induced to neuronal differentiation by butyrate treatment. Neurofilaments, p53, and DNA-synthesizing nuclei labeled with 5-bromodeoxyuridine were immunostained, and apoptotic cells were labeled by in situ DNA nick end labeling (TUNEL). We combined these immunostaining and labeling methods to determine whether the cells expressed these markers at the same time. DNA fragmentation and p53 levels were also determined by electrophoresis. RESULTS: Y-79 cells proliferated in the synthetic medium. After butyrate treatment, they extended protrusions and increased neurofilament immunoreactivity. The differentiated features were striking on day 7. Thereafter, differentiated cells decreased and apoptotic cells increased. DNA synthesis was detected in the cells expressing immunoreactivity for neurofilaments or p53. At day 7, most of the cells with p53-positive nuclei were alive and neurofilament-positive. However at day 10, the p53-positive cells were apoptotic and neurofilament-positive apoptotic cells accumulated. CONCLUSIONS: We conclude that the Y-79 cells express p53 and undergo apoptosis after neuronal differentiation. There could be a p53-dependent apoptotic pathway in butyrate-induced differentiated Y-79 cells due to the inability to regulate cell cycling.

Reassessment of K-ras mutations at codon 12 by direct PCR and sequencing from tissue microdissection in human pancreatic adenocarcinomas.

K-ras mutations at codon 12 have been detected in almost all pancreatic adenocarcinomas by highly sensitive assays. We reassessed the K-ras mutation status by direct polymerase chain reaction (PCR) and sequencing from tissue microdissection without DNA extraction in 10 pancreatic adenocarcinomas, and also assessed the K-ras and DPC4 genes in nine pancreatic cancer cell lines. Eight pancreatic adenocarcinomas were found to harbor K-ras mutations at codon 12 of either GTT or GAT, five of which were inferred to harbor amplified mutant alleles. Mutations at the sites other than codon 12 were found in seven of 70 clones (seven of 9,380 bases) by the TA cloning analysis, suggesting that artifactual mutations at the first or second base of codon 12 before and during PCR could occur at a frequency of approximately 10(-3), enough for highly sensitive assays to detect. Two cell lines without K-ras mutations at codon 12 were found to have homozygous deletions at the DPC4 gene. Thus the K-ras mutation status was demonstrated to be correctly determined by just direct sequencing from tissue microdissection. All possible mutations or multiple mutations at K-ras codon 12 that have been reported in pancreatic adenocarcinomas might include artifacts or mutations without a selective advantage. In addition, we must be very cautious about contamination.

Extent of pathologic invasion of the inferior vena cava in resected liver cancer compared with possible caval invasion diagnosed by preoperative images.

The extent of cancerous invasion of the inferior vena cava (IVC) determined from resected liver cancer was examined pathologically. Ten patients presenting with liver cancer (metastatic liver cancer, five patients; hepatocellular carcinoma, three; and cholangiocellular carcinoma, two) were diagnosed with positive IVC invasion using preoperative imaging techniques of extracorporeal ultrasonography, computed tomography, magnetic resonance imaging, and vena cavography. The diagnostic criterion for positive IVC invasion by preoperative imaging was longitudinal IVC compression measuring over 50 mm, or transverse IVC compression extending to more than half the circumference of the IVC, or the presence of lesions protruding into the IVC lumen, or the presence of developed collateral veins. All patients underwent combined resection of the IVC. However, pathology results revealed that four of the ten patients had no cancerous invasion of the IVC, and that the extent of invasion along both the longitudinal and transverse axes of the IVC was much smaller than the compression shown by imaging results. We believe that detailed preoperative assessment, using a more precise imaging technique, as well as further intraoperative examination, is required to predict the full pathological extent of cancerous invasion of the IVC.

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1998)].

The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and analyzed some characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In these 18 institutions around the entire Japan, 532 strains of presumably etiological bacteria were isolated mainly from the sputa of 438 patients with lower respiratory tract infections during the period from October in 1998 to September in 1999. MICs of various antibacterial agents and antibiotics were determined against 85 strains of Staphylococcus aureus, 100 strains of Streptococcus pneumoniae, 96 strains of Haemophilus influenzae, 75 strains of Pseudomonas aeruginosa (non-mucoid strains), 6 strains of Pseudomonas aeruginosa (mucoid strains), 38 strains of Moraxella subgenus Branhamella catarrhalis, 26 strains of Klebsiella pneumoniae etc., and the susceptibilities of 517 strains were assessed except for those strains that died during transportation. S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus: MRSA) accounted for 60.0%. Vancomycin (VCM) and arbekacin (ABK) showed the most potent activities against MRSA. But one of MRSA showed resistance to ABK with the MIC of 64 micrograms/ml. The sensitive strains of MRSA to VCM have decreased. The frequency of penicillin (PC)-intermediate S. pneumoniae (PISP) + PC-resistant S. pneumoniae (PRSP) have increased in 46.0% for 1998 comparatively from 30.9% of 1997's. But PRSP decreased, and PISP increased into 39.0% of 1998 years from 19.8% of 1997's. Panipenem (PAPM), imipenem (IPM) and faropenem (FRPM) showed the most potent activities against S. pneumoniae with MIC80s of 0.125 microgram/ml or below. Against H. influenzae and M. (B.) catarrhalis, almost all the drugs showed good activities. The sensitive strains of them against ceftazidime (CAZ) decreased in 1997, but those have increased in 1998. Inversely, the susceptibility of them against cefotiam (CTM) had been higher in 1997, but those have been lower in 1998. Tobramycin (TOB) showed the most potent activity against P. aeruginosa (both mucoid and nonmucoid strains). All drugs except ampicillin (ABPC) were active against K. pneumoniae. A quite few of K. pneumoniae showed low susceptibilities. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. The examination of age distribution indicated that the proportion of patients with ages over 70 years was 48.6% of all the patients showing a slight increase in every year. About the proportion of diagnosed diseases as follows: Bacterial pneumonia was the most frequent with 40.2%. The ratio of it has increased slightly, and the increased rate was 10% in patients with ages over 70 years compared with the results in 1997. Chronic bronchitis have decreased slightly with 27.6% in 1998. Number of strains isolated from patients before administration of antibiotics were more than those after administration of them in chronic bronchitis, but these were almost same number in bacterial pneumonia. Administration of antibiotics has changed the results of the frequency of isolation of bacterial species. Bacterial isolations before administration of antibiotics were as follows: S. pneumoniae 26.7%, H. influenzae 23.8%, S. aureus 13.3% and M. (B.) catarrhalis 10.8%. The frequencies of S. aureus decreased after antibiotics administration over 15 days, but the frequencies of P. aeruginosa (both mucoid and non-mucoid) was not affected. The frequencies of P. aeruginosa was 45.5% after administration over 15 days. The frequencies of S. pneumoniae decreased upon administration of antibiotics, these were only 4.5% over 15 days. The frequencies of H. (

Effect of removal of caecal contents on nitrogen utilisation and nitrogen excretion in caecally ligated chickens fed on a low protein diet supplemented with urea.

1. The effect of washing out the caecal contents on nitrogen utilisation and nitrogen excretion were examined in Single Comb White Leghorn cockerels fed on a 50 g/kg protein diet supplemented with urea. 2. Flushing out the caecal contents with saline in caecally ligated chickens produced a significantly increased nitrogen balance and increased nitrogen utilisation (P<0.05). 3. Washing out the caecal contents significantly decreased uric acid excretion but the treatment had no effect on urea and ammonia excretion. 4. Caecal bacterial contents were significantly decreased by caecal ligation and decreased further by washing out the caecal contents. 5. It is concluded that nitrogen metabolism in chickens is affected by possible changes in caecal fermentation produced by preventing substances from urine and digesta from entering the caeca.

Effect of caecectomy on growth, moisture in excreta, gastrointestinal passage time and uric acid excretion in growing chicks.

1. The effect of caecectomy on nitrogen utilisation and excretion was examined in growing chicks fed on a commercial diet. 2. Caecectomy had no significant effect on food intake or body weight gain. 3. Caecectomy caused significantly higher moisture content in excreta (P<0.01). 4. Gastrointestinal passage time of digesta was significantly shorter in caecectomised chicks than in control chicks (P<0.05). 5. Caecectomy tended to improve nitrogen utilisation rate in growing chicks. 6. The treatment significantly decreased uric acid excretion (P<0.01) and excretory uric acid-N/total nitrogen excretion (P<0.01). 7. It is concluded that the effects of caecectomy on nitrogen metabolism in growing chicks are similar to those in adult chickens.

Effect of calcium channel blockers on cerebral ischemia-induced hyperactivity in Mongolian gerbils.

When both common carotid arteries of Mongolian gerbils were occluded for 5 min to produce ischemic insult, locomotor activity was increased the following day. The effect of calcium channel blockers on this ischemia-induced hyperactivity was investigated. Nimodipine, at doses of 5, 10, and 20 mg/kg, dose dependently and significantly decreased ischemia-induced hyperactivity. Nicardipine significantly decreased ischemia-induced hyperactivity and doses of 10 and 20 mg/kg. Nifedipine and flunaridine also significantly decreased ischemia-induced hyperactivity at doses of 20 mg/kg. Verapamil had no effect on ischemia-induced hyperactivity at a dose of 20 mg/kg. These findings suggest that ischemia-induced hyperactivity is related to calcium channels. These relationship between calcium channels and dopaminergic function is discussed.

Effect of dopamine blockers on cerebral ischemia-induced hyperactivity in gerbils.

When common carotid arteries of Mongolian gerbils were clamped for 5 min, locomotor activity significantly increased the day after the ischemic insult. This hyperactivity induced by cerebral ischemia was evident in both light and dark periods. The significant increases in locomotor activity seen in both periods were noted for 3 and 9 days after occlusion, respectively. Effects of dopamine receptor antagonists on the ischemia-induced hyperactivity were investigated the day after the ischemia insult. Haloperidol, sulpiride, and eticlopride, all dopamine D2 receptor antagonists, decreased the ischemia-induced hyperactivity at doses that had no effects on locomotor activity in sham-operated animals. SCH23390, a dopamine D1 receptor antagonist, had no clear effects on the ischemia-induced hyperactivity. Clozapine, with not so high an affinity for the dopamine D2 receptor decreased the ischemia-induced hyperactivity when given in a relatively high dose. Thus, the ischemia-induced hyperactivity is apparently related to abnormalities in dopaminergic functions, particularly the dopamine D2 receptor.

Significant role of the nitrogen recycling system through the ceca occurs in protein-depleted chickens.

This study focuses on the role of the ceca in nitrogen nutrition in chickens (Gallus domesticus). Urea is a very good nitrogen tracer for these studies. Little urea is synthesized by chickens due to the absence of carbamyl phosphate synthetase, an essential enzyme initiating the urea cycle. Urea is utilized by chickens when crystalline amino acid diets low in nonessential nitrogen or diets containing low concentrations of intact protein are fed, and most ureolytic activity is found in the ceca. Dietary urea was absorbed intact from the upper intestine of the chicken. The absorbed urea was excreted into ureteral urine that refluxed from the cloaca into the colon and ceca where urea was degraded to ammonia. Presumably the ammonia was incorporated into amino acids by cecal microorganisms and some urea, amino acids and proteins were absorbed from the ceca. These were utilized by the chickens. A beneficial role of ceca in the nitrogen metabolism in the chicken is, therefore, conservation of urinary nitrogen in protein-depleted chickens.