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E Harada

Publications and source records attributed to E Harada.

At least 73 records · Page 4Linked to original sources
PubMed1989

Analysis of colostral proteins in calf serum by enzyme-linked immunosorbent assay.

Enzyme-linked immunosorbent assay method was improved to monitor the concentrations of colostral proteins in the range of 10 to 10(3) ng/ml in calf serum. Colostral proteins were purified from fat-free colostrum, and antibodies against them were prepared from the rabbit anti-colostrum protein sera. Concentration of each protein was determined by enzyme-linked immunosorbent assay without interference by calf serum proteins in a mixture of colostrum and precolostral calf serum. Changes in the colostral protein concentrations in the sera of five postcolostral calves were monitored by enzyme-linked immunosorbent assay. After feeding colostrum to the neonatal calf, serum IgG concentration increased rapidly within 16 h to 8.1 to 36.8 mg/ml and gradually declined until 3 d to the steady levels, 4.7 to 23.6 mg/ml. The concentrations of casein and P2 (colostral small proteins, which were eluted at the second peak in Sephadex G-100 gel filtration) also increased more rapidly within 16 h to 9.6 to 264.0 micrograms/ml and 31.5 to 1600 micrograms/ml, respectively, and steeply decreased to near the detection limit on 3 d after feeding. These results indicate that enzyme-linked immunosorbent assay is useful to measure and monitor the absorbed colostral proteins and also to survey calves receiving and not receiving colostrum.

Animals↗
PubMed1988

Biliary and pancreatic exocrine secretions via endogenous secretin by intestinal infusion of propionate and propionate analogues in piglets.

1. The secretory responses of hepatic bile and exocrine pancreas by intraduodenal infusion of propionate (PA), 3Cl-PA, 2Cl-PA, 3Br-PA and 2Br-PA solutions were examined in anesthetized piglets. 2. Pancreatic juice and protein secretions were enhanced by infusion of PA and PA analogue solutions of pH 2.0 following increase of plasma secretin level but not pH 7.0. The order of response time was as follows: 3Br-PA greater than 2Cl-PA greater than 2Br-PA greater than 3Cl-PA greater than PA. 3. The response of bile flow depended on endogenous secretin and showed almost the same pattern as that of pancreatic juice secretion. 4. The results suggested that pancreatic exocrine secretion via endogenous secretin was not always dependent on the dissociation constant of weak acids.

Animals↗
PubMed1988

Postnatal development of biliary and pancreatic exocrine secretion in piglets.

1. The secretory responses of bile and exocrine pancreas were studied in various aged piglets. 2. At 3 days old the bile and exocrine pancreas could be reacted by various stimulations. The response by secretin was the same as that in the 28 day old. 3. Protein concentration in pancreatic juice by CCK-8 increased steeply after 6 days old, but the ratio of amylase to protein rose abruptly at 28 days old. 4. These findings indicate that (1) the secretory capacity of bile and pancreatic juice developed predominantly at an early period of postnatal life; (2) the formation of bile acids and pancreatic digestive enzymes developed gradually during the suckling period.

Age Factors↗
PubMed1987

Cytochrome reduction induced by increase in extracellular potassium and by electrical stimulation in isolated perifused neurohypophysis of guinea pig under mild hypoxic conditions.

Parallel reduction of cytochromes, a(a3), b and c + c1 was recorded under mild hypoxic conditions when the neurohypophysis was electrically stimulated and extracellular KCl concentration was increased. The electrically stimulated reduction was abolished by tetrodotoxin and by replacement of NaCl with LiCl. The reduction was not influenced by removal of extracellular Ca2+, or by application of a Ca ionophore, A23187. These results show that cytochrome reduction correlates with K+-influx in the resting state, and with Na+-influx followed by activation of the neurosecretory terminals contained in the neurohypophysis.

Animals↗
PubMed1987

[Direct priming effects beyond words: a case of word pairs].

One important issue in direct priming research is whether or not priming effects are restricted to single words. Four series of experiments were conducted with word pairs. The reading time was measured for physically inverted word pairs written in katakana characters. The results indicated that the direct priming effect was obtained with word pairs regardless of the task condition, perceptual or semantic. The important thing is whether the task is processed in an integrated manner or not.

Cognition↗
PubMed1986

Hepatic bile and pancreatic exocrine secretions evoked by gastrointestinal peptides in sheep.

The secretory response of hepatic bile and exocrine pancreas to gastrointestinal peptides has been studied in chronically cannulated sheep. Pancreatic juice flow and protein output were evoked dose dependently by intraportal injection of secretin, CCK-8, caerulein, VIP and neurotensin. However, biliary secretion was evoked by only secretin. Biliary and pancreatic exocrine secretions were enhanced by delivered gastric juice into the duodenum as followed by the increased plasma concentration of immunoreactive secretin (IRS). Results suggest that secretin is the major peptide that regulates pancreatic exocrine secretion and hepatic bile production in the sheep.

Animals↗
PubMed1986

Comparison of pancreatic exocrine secretion via endogenous secretin by intestinal infusion of hydrochloric acid and monocarboxylic acid in anesthetized piglets.

The secretory response of the exocrine pancreas via endogenous secretin (IRS) by intraduodenal instillation of hydrochloric acid (HCl) and various monocarboxylic acid solutions was studied in anesthetized piglets. The secretion induced by HCl solutions of various concentrations containing 250 mM NaCl occurred when pH of the solutions was lower than 1.5. After instillation of the HCl solution of pH 1.0, juice flow and protein output increased 26 times and 9 times, respectively, as compared with basal levels. Such pancreatic responses paralleled an increase in plasma IRS concentration in the portal vein. The pancreatic response induced by a lactic acid solution occurred when pH of the solutions was lower than 3.8. The juice flow and protein output stimulated by a lactic acid solution of 250 mM and pH 2.0 were 16 and 8 times higher than the basal levels. The responses to the lactic acid solution of pH 2.0 increased concentration dependently, and were followed by an increase in IRS concentration in the portal vein. The pancreatic exocrine responses induced by other monocarboxylic acid solutions (250 mM) of pH 2.0 were in the following order: formic acid greater than lactic acid greater than pyruvic acid much greater than acetic acid greater than butyric acid greater than propionic acid. Lactamide, an analogous substance of lactic acid, did not evoke any pancreatic secretion. The results indicate the possibility that pancreatic exocrine response induced by HCl is dependent upon hydrogen ion, while the response induced by monocarboxylic acid is not always dependent on dissociation constant of acid.

Anesthesia↗
PubMed1985

Comparison of pancreatic digestive enzyme secretion induced by volatile fatty acids in mice, Japanese field voles and goats.

The secretory response of the exocrine pancreas to volatile fatty acids was investigated in the isolated preparations of mice, Japanese field voles and goats. The amylase content in pancreases of the voles was half that of the mice, and the trypsin content was four times higher than that of the mice. Amylase release to volatile fatty acids in the goats showed a dose-dependent relationship. The response in the voles was obtained by acetate and propionate, but preparations in the mice were ineffective in response to volatile fatty acids. The results indicate that the pancreatic digestive enzyme secretory function in voles resembles that of ruminants.

Amylases↗
PubMed1984

Inhibitory influence of amino acids on secretagogues induced exocrine secretion in isolated perfused rat pancreas.

Influence of amino acids upon pancreatic exocrine secretion has been investigated in the isolated perfused pancreas of rats. Arg produced significant and dose-related inhibition of pancreatic juice flow, protein output and amylase output evoked by CCK-PZ (1.25 pM). The secretory response evoked by CCK-PZ was inhibited by other amino acids (Ala, Asp, Asn, Gly, Ile, Leu, Lys, Met, Phe, Pro, Thr, Trp, Val, in each 20 mM). A similar inhibitory pattern was observed using 10 mixed amino acids of 2 mM each (Pro, Phe, Thr, Met, Lys, Asp, Leu, Trp, Val, Gly). Gly at a concentration of 20 mM produced significant inhibition of exocrine secretion evoked by ACh (50 nM) or GRP (36 pM). The inhibitory response induced by amino acids could not be repeated by using exogenous insulin (1 microM) and glucagon (280 nM). The inhibitory response was also not changed by increased extracellular Ca (5 or 10 mM). However, Gly (20 mM) produced inhibition of exocrine secretion evoked by Ca reintroduction into a pancreas which was pretreated with A 23187. It was suggested that the inhibitory effects of some amino acids on exocrine secretion are mainly caused by suppression of Ca influx in a stimulus-secretion coupling process.

Acetylcholine↗
PubMed1983

Effect of short-chain fatty acids on the secretory response of the ovine exocrine pancreas.

The secretory response of the exocrine pancreas to short-chain fatty acids has been studied in anesthetized sheep and in isolated lobules. Butyrate, propionate, and acetate stimulated pancreatic juice flow and protein and amylase output in the anesthetized sheep. The secretory response to butyrate was significantly greater than that of propionate or acetate. Rapid intravenous injection of butyrate (625 mumol/kg) caused a 13-fold rise in the juice flow, 26-fold in protein output, and 37-fold in amylase output above the basal levels within 5 min and declined to basal levels over a period of 30 min. Responses to butyrate (625 mumol/kg) were comparable with those obtained with 2 U/kg pancreozymin (Boots). Detectable responses were obtained with 15 mu/kg butyrate, 125 mumol/kg propionate, and 312.5 mumol/kg acetate. The secretory response to butyrate (625 mumol/kg) was not affected by pretreatment with atropine and hexamethonium. In the isolated lobule preparation, amylase release increased in response to butyrate in a concentration-dependent manner, reaching a maximal level at 1 mM and declining at 100 mM. It is concluded that short-chain fatty acids act directly on pancreatic acinar cells to stimulate secretion. The physiological implications of these findings are considered.

Acetates↗
PubMed1982

Cold acclimation in insulin secretion of isolated perfused pancreas of the rat.

The secretory function of the endocrine and exocrine pancreas in the process of cold acclimation has been studied in rats fed at an ambient temperature of 2 degrees C. In anesthetized rats, plasma glucose decreased immediately after cold exposure and increased again toward the basal level after 20 days of continuous cold exposure. Plasma insulin level in these rats also decreased immediately after cold exposure, and the low level was maintained throughout the whole period of cold exposure. In the isolated perfused rat pancreas, the basal insulin output estimated before the stimulation with glucose decreased immediately after the cold exposure and increased gradually during the continuous cold exposure. In these preparations, the initial and the second phases of insulin output were induced by sustaining stimulation with 16.7 mM glucose. Changes in the glucose-induced initial and second phases showed a diphasic pattern during the course of cold exposure. Thus, there was temporary decrease within a week of cold exposure followed by a gradual increase after 3 wk of this condition. The diphasic insulin output in the preparation isolated from rats fed during cold exposure for 6 wk was twice as much as that in the preparation isolated from the rats fed during exposure to 23 degrees C for 5 wk. In the isolated perfused rat pancreas, a monophasic insulin output was induced by sustaining stimulation with 0.1 microM ACh. The monophasic insulin output showed an increasing tendency during cold exposure, but the increase was insignificant because of a larger individual variation.

Acetylcholine↗
PubMed1979

Stimulation of renin secretion from the intact kidney and from isolated glomeruli by the calcium ionophore A23187.

The ionophore A23187 evoked a dose-dependent release of renin from the isolated perfused cat kidney, which was inhibited by calcium deprivation and adrenergic blockade. The latter finding indicates that the effects of A23187 on the intact kidney are mediated mainly by catecholamine release from sympathetic nerve endings. Ionophore also elicited a concentration-dependent enhancement of renin secretion from a pure preparation of glomeruli isolated from cat kidney; this stimulation was still manifest when the glomeruli were superfused with a calcium-free solution. These findings indicate that A23187 evokes renin secretion from juxtaglomerular cells by mobilizing cellular calcium and support the view that an increase in intracellular calcium is intimately involved in the mechanism of renin secretion.

Animals↗
PubMed1978

Stimulation of renin secretion and calcium efflux from the isolated perfused cat kidney by noradrenaline after prolonged calcium deprivation.

1. The effects of noradrenaline on the secretion of renin and on the efflux of Ca have been investigated in the isolated cat kidney perfused with Locke solution containing the alpha-adrenergic blocking agent, phenoxybenzamine, to block increases in renal vascular resistance. 2. Noradrenaline elicited a marked increase in renin secretion in the absence of any discernible alterations in renal arterial pressure, and prolonged perfusion with Ca-free Locke solution failed to depress noradrenaline-evoked renin secretion. 3. Noradrenaline caused an increase in the efflux of 45Ca from prelabelled kidneys perfused with Ca-free solution. Increasing the noradrenaline concentration produced graded increases in 45Ca efflux and renin release, and the peak rise in efflux preceded or coincided with peak renin secretion. 4. DL-Propranolol inhibited the increase in 45Ca efflux and renin release resulting from noradrenaline stimulation. 5. Electrical stimulation of the renal nerve enhanced 45Ca efflux and renin release from prelabelled kidneys perfused with noraml Locke solution. 6. These findings provide further support for the view that the process of catecholamine-induced renin secretion involves mobilization of Ca from a cellular site.

Animals↗