In vitro study of antral gastrin biosynthesis in response to weaning and corticosterone acetate in rats

1986 ◽  
Vol 111 (4) ◽  
pp. 539-545 ◽  
Author(s):  
Hiroyasu Okahata ◽  
Yoshikazu Nishi ◽  
Kotaro Muraki ◽  
Koji Sumii ◽  
Ko Tanaka ◽  
...  
Keyword(s):  
Single Dose ◽  
Breast Milk ◽  
Gel Filtration ◽  
In Vitro Study ◽  
Physiological Saline ◽  
Solid Food ◽  
Adult Level ◽  
Old Rats ◽  
Corticosterone Treatment

Abstract. The effects of weaning (abrupt dietary changes from breast milk to solid food) and corticosterone injection on antral gastrin-like immunoreactivity (G-LI) concentrations and antral G-LI biosynthesis were studied in rats. A single dose of corticosterone acetate was injected in one group of 7 day old rats, and a single dose of physiological saline was injected in another. Each group of rats was divided into two subgroups, one fed only rat breast milk until 25 days old and the other weaned at day 21. In non-corticosterone treated unweaned rats, antral G-LI did not increase. In non-corticosterone treated weaned rats, antral G-LI was constant before weaning, then increased 4-fold to the adult level. In corticosterone treated unweaned rats, the antral G-LI on day 11 was twice than on day 7, and thereafter remained constant. In corticosterone treated weaned rats, antral G-LI increased after corticosterone treatment and increased again after weaning to reach the adult level at day 25. Gel filtration of pulse-chase incubated antral samples with l-[methyl-3H]methionine from unweaned rats without corticosterone administration showed Vo, fraction 19 (Fr. 19) and gastrin-34 (G34) peaks, but no gastrin-17 (G17) peak after 60 min of chase incubation, but at 120 min of chase incubation a G17 peak was present; corticosterone-treated and/or weaned (solid food alone) rat samples showed Vo, Fr. 19, G34 and G17 peaks at 30 min of pulse incubation.

Development of gastric somatostatin-like immunoreactivity in response to corticosterone acetate and dietary changes in young rats

1986 ◽  
Vol 112 (3) ◽  
pp. 383-387 ◽  
Author(s):  
Hiroyasu Okahata ◽  
Yoshikazu Nishi ◽  
Kotaro Muraki ◽  
Koji Sumii ◽  
Yukitaka Miyachi ◽  
...  
Keyword(s):  
Single Dose ◽  
Breast Milk ◽  
Gel Filtration ◽  
Physiological Saline ◽  
Solid Food ◽  
Adult Rats ◽  
Dietary Changes ◽  
Adult Level ◽  
Milk Feeding ◽  
Somatostatin 14

Abstract. The effects of dietary changes from breast milk to solid food and corticosterone acetate administration on somatostatin-like immunoreactivity (SLI) in the gastric antrum and corpus were studied in young and adult rats. At 7 days of age, a single dose of corticosterone acetate (250 mg/kg of body weight) was injected in one group of rats, and a single dose of physiological saline was injected in another group. Each group was divided into two subgroups; one was fed only rat breast milk until 25 days of age and the other weaned (solid food alone) at 21 days of age. Gastric antrums and corpora were removed at various ages for assay of SLI concentrations by radioimmunoassay. In non-corticosterone treated rats, antral and corpus SLI increased gradually until 20 days of age, and after changing from breast milk to solid food on day 21 antral SLI increased 2-fold to the adult level, whereas corpus SLI remained constant. In corticosterone-treated rats, antral and corpus SLI on day 11 was 5-fold that on day 7, and thereafter remained constant before changing from breast milk to solid food; after weaning (solid food alone) antral SLI increased again to reach the adult level at 25 days of age whereas corpus SLI remained constant after weaning. Prolonged breast milk feeding alone did not influence antral or corpus SLI levels in either corticosterone-treated or non-treated rats as compared to levels on day 20. Gel filtration of antral and corpus SLI from 15 day old corticosterone-treated and non-treated, and 25 day old weaned (solid food alone) and unweaned (breast milk alone) rats showed almost the same results: only one peak coeluted with synthetic somatostatin-14. The resuits suggest that weaning (solid food alone) and corticosterone administration affect the antral and corpus SLI.

Hypoxia and acidosis increase the secretion of catecholamines in the neonatal rat adrenal medulla: an in vitro study

2005 ◽  
Vol 289 (6) ◽  
pp. C1417-C1425 ◽  
Author(s):  
A. J. Rico ◽  
J. Prieto-Lloret ◽  
C. Gonzalez ◽  
R. Rigual
Keyword(s):  
Adrenal Medulla ◽  
In Vitro Study ◽  
Neonatal Rat ◽  
Hypercapnic Acidosis ◽  
Hypoxic Response ◽  
High K ◽  
Old Rats ◽  
The Subject ◽  
Direct Sensitivity

Hypoxia elicits catecholamine (CA) secretion from the adrenal medulla (AM) in perinatal animals by acting directly on chromaffin cells. However, whether innervation of the AM, which in the rat occurs in the second postnatal week, suppresses this direct hypoxic response is the subject of debate. Opioid peptides have been proposed as mediators of this suppression. To resolve these controversies, we have compared CA-secretory responses with high external concentrations of K+ ([K+]e) and hypoxia in the AM of neonatal (1- to 2-day-old) and juvenile (14- or 15- and 30-day-old) rats subjected to superfusion in vitro. In addition, we studied the effect of hypercapnic acidosis on the CA-secretory responses in the AM during postnatal development and the possible interaction between acidic and hypoxic stimuli. Responses to high [K+]e were comparable at all ages, but responses to hypoxia and hypercapnic acidosis were maximal in neonatal animals. Suppression of the hypoxic response in the rat AM was not mediated by opioids, because their agonists did not affect the hypoxic CA response. The association of hypercapnic acidosis and hypoxia, mimicking the episodes of asphyxia occurring during delivery, generates a more than additive secretory response in the neonatal rat AM. Our data confirm the loss of the direct sensitivity to hypoxia of the AM in the initial weeks of life and demonstrate a direct response of neonatal AM to hypercapnic acidosis. The synergistic effect of hypoxia and acidosis would explain the CA outburst crucial for adaptation to extrauterine life observed in naturally delivered mammals.

scholarly journals A prophylactic multi-strain probiotic treatment to reduce the absorption of toxic elements: In-vitro study and biomonitoring of breast milk and infant stools

2019 ◽  
Vol 130 ◽  
pp. 104818 ◽  
Author(s):  
Maria Luisa Astolfi ◽  
Carmela Protano ◽  
Elisa Schiavi ◽  
Elisabetta Marconi ◽  
Daniela Capobianco ◽  
...  
Keyword(s):  
Breast Milk ◽  
Toxic Elements ◽  
In Vitro Study ◽  
Vitro Study ◽  
Probiotic Treatment

Influence of diet on the development of antral gastrin-like immunoreactivity in the stomach of rats

1989 ◽  
Vol 120 (3) ◽  
pp. 374-378 ◽  
Author(s):  
Hiroyasu Okahata ◽  
Yoshikazu Nishi ◽  
Kotaro Muraki ◽  
Masaru Arai ◽  
Norio Kubo ◽  
...  
Keyword(s):  
Breast Milk ◽  
Gel Filtration ◽  
Essential Nutrients ◽  
Young Rats ◽  
Rich Food ◽  
Old Rats ◽  
The Individual ◽  
Milk Feeding

Abstract. The effects of individual food constituents on antral gastrin-like immunoreactivity concentrations were studied in young rats. Rats aged 7 to 20 days were given only rat breast milk and then weaned by various nutrients (regular laboratory chow, protein (ovalbumin)-, fat- or carbohydrate (starch)-rich food). Rats receiving rat breast milk only until 27 days of age were also studied. In rats on regular laboratory chow, antral gastrin-like immunoreactivity increased and reached adult levels on day 25. In rats on ovalbumin, fat-rich food or starch, it increased on day 23 but dropped thereafter. The increment by laboratory chow was higher than that by the individual nutrients. No increase was observed during milk feeding alone. Gel filtration of antral gastrin-like immunoreactivity from 25-day-old rats on laboratory chow or three essential nutrients showed the same results.

scholarly journals Opposite Effects of Single-Dose and Multidose Administration of the Ethanol Extract of Danshen on CYP3A in Healthy Volunteers

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Furong Qiu ◽  
Jian Jiang ◽  
Yueming Ma ◽  
Guangji Wang ◽  
Chenglu Gao ◽  
...  
Keyword(s):  
Single Dose ◽  
Healthy Volunteers ◽  
Plasma Concentrations ◽  
In Vitro Study ◽  
Ethanol Extract ◽  
Tanshinone Iia ◽  
Open Label ◽  
The Mean

The aim of this study was to investigate the effect of single- and multidose administration of the ethanol extract of danshen on in vivo CYP3A activity in healthy volunteers. A sequential, open-label, and three-period pharmacokinetic interaction study design was used based on 12 healthy male individuals. The plasma concentrations of midazolam and its metabolite 1-hydroxymidazolam were measured. Treatment with single dose of the extract caused the meanCmaxof midazolam to increase by 87% compared with control. After 10 days of the danshen extract intake, the mean AUC0–12,Cmax, andt1/2of midazolam were decreased by 79.9%, 66.6%, and 43.8%, respectively. The mean clearance of midazolam was increased by 501.6% compared with control. The in vitro study showed that dihydrotanshinone I in the extract could inhibit CYP3A, while tanshinone IIA and cryptotanshinone could induce CYP3A. In conclusion, a single-dose administration of the danshen extract can inhibit intestinal CYP3A, but multidose administration can induce intestinal and hepatic CYP3A.

Origin of Soluble Crosslinked Fibrin Oligomers: An in Vitro Study

1979 ◽  
Author(s):  
R. Hafter ◽  
R.V. Hugo ◽  
H. Graeff
Keyword(s):  
Gel Filtration ◽  
In Vitro Study ◽  
In Vitro Studies ◽  
Vitro Study ◽  
Simultaneous Action ◽  
Contrast Reaction ◽  
Combined Action ◽  
Fibrin Clots

In patients with DIC crosslinked high molecular fibrin derivatives (CL-HMD)are observed, which are eluted by gel filtration in the exclusion volume (MW>106 ). Characterization by PAGE revealed that their subunits are similar to crosslinked fdp X. To evaluate their origin, in vitro studies were performed on fibrinolysis products obtained in three ways; (1) by SK-induced fibrinolysis of crosslinked fibrin, (2) by simultaneous action of thrombin and plasmin on Fg in presence of F XIII and Ca++, and (3) by limited fibrinogenolysis and subsequent action of thrombin and F XIII upon the resultant early FDP. Reaction (1) resulted in low mol derivatives (LMD) only (D-D, E ), which do not complex with Fg. In contrast, reaction (2) and (3) resulted in HMD and LMD. The former are composed of Cl-‘X’ and complexes of mainly ‘X’ and ‘Y’. In reaction (3) early X precipitates when it is transformed to ‘X’ and to CL-’X’. Late X remains soluble after transition to ‘X’ and CL-’X’. The results suggest, that CL-HMD observed in patients with DIC are not derived from fibrin clots but formed from Fg under combined action of plasmin and thrombin

scholarly journals Fluoride Ion Release Characteristics of Fluoride-Containing Varnishes—An In Vitro Study

2021 ◽  
Vol 11 (4) ◽  
pp. 1452
Author(s):  
Sachin Chhatwani ◽  
Jennifer Hoppe ◽  
Ella A. Naumova ◽  
Wolfgang H. Arnold ◽  
Stephan C. Möhlhenrich ◽  
...  
Keyword(s):  
Single Dose ◽  
In Vitro Study ◽  
White Spot ◽  
Control Group ◽  
Fluoride Ion ◽  
Fluoride Release ◽  
White Spot Lesions ◽  
Ion Release ◽  
One Step

Despite the latest advances in orthodontic treatment, white spot lesions remain a common side effect of fixed appliance therapy. An effective treatment for the prevention of white spot lesions is the use of fluoride-containing products. The aim of the present in vitro study was to check the durability of the tested products for their fluoride release into the surrounding solution. Three varnishes (Protecto CaF2 Nano one-step seal, Bifluorid 12 single dose, and Fluor Protector S) were applied to hydroxyapatite discs and kept in diluted Total Ionic Strength Adjustment Buffer III (TISAB III) solution for fluoride ion release measurement. A group of clear hydroxyapatite discs served as the control group. The carrier discs (N = 40) underwent three thermal cycling runs for 20 days. Before the first run and after each run, the fluoride ion concentration in the solution was measured at appointed times (T) T0, T1, T2, and T3. Fluoride ion release was highest at T1 for all products (median values for Protecto CaF2 Nano one-step seal: 0.09 ppm, Bifluorid 12 single dose: 37.67 ppm, and Fluor Protector S: 3.36 ppm) except for the control group, showing its peak at T0 (0.04 ppm). There was a significant difference between the tested fluoride varnishes at all measurement times. Bifluorid 12 achieved significantly higher fluoride release values than the other products (p < 0.05 at all measurement times). A solitary product application of only once or twice per year, as stated by the manufacturers, cannot be supported.

scholarly journals The stoichiometry of the nucleoporin 62 subcomplex of the nuclear pore in solution

2014 ◽  
Vol 25 (9) ◽  
pp. 1484-1492 ◽  
Author(s):  
Alexander Ulrich ◽  
James R. Partridge ◽  
Thomas U. Schwartz
Keyword(s):  
Analytical Ultracentrifugation ◽  
Protein Complexes ◽  
Gel Filtration ◽  
Coiled Coil ◽  
In Vitro Study ◽  
Nuclear Pore ◽  
Binding Partner ◽  
Repeat Proteins ◽  
Complex Forms

The nuclear pore complex (NPC) regulates transport between the nucleus and cytoplasm. Soluble cargo-protein complexes navigate through the pore by binding to phenylalanine-glycine (FG)-repeat proteins attached to the channel walls. The Nup62 complex contains the FG-repeat proteins Nup62, Nup54, and Nup58 and is located in the center of the NPC. The three proteins bind each other via conserved coiled-coil segments. To determine the stoichiometry of the Nup62 complex, we undertook an in vitro study using gel filtration and analytical ultracentrifugation. Our results reveal a 1:1:1 stoichiometry of the Nup62 complex, where Nup54 is central with direct binding to Nup62 and Nup58. At high protein concentration, the complex forms larger assemblies while maintaining the Nup62:Nup54:Nup58 ratio. For the homologous Nsp1 complex from Saccharomyces cerevisiae, we determine the same stoichiometry, indicating evolutionary conservation. Furthermore, we observe that eliminating one binding partner can result in the formation of complexes with noncanonical stoichiometry, presumably because unpaired coiled-coil elements tend to find a promiscuous binding partner. We suggest that these noncanonical stoichiometries observed in vitro are unlikely to be physiologically relevant.

Microwave Plasma Sintering and In Vitro Study of Porous HA/β-TCP Biphasic Bioceramics

2007 ◽  
Vol 280-283 ◽  
pp. 1519-1524 ◽  
Author(s):  
Jin Gou Ji ◽  
Jun Guo Ran ◽  
Li Gou ◽  
Fang Hu Wang ◽  
Lu Wei Sun
Keyword(s):  
Body Fluid ◽  
Microwave Plasma ◽  
In Vitro Study ◽  
Physiological Saline ◽  
Biological Properties ◽  
Densification Rate ◽  
Living Body ◽  
Conventional Furnace ◽  
Plasma Sintering

Porous HA/β-TCP biphasic calcium phosphate (BCP) bioceramics were prepared by microwave plasma in order to solve the problems on sintering of Ca-P bioceramics by a conventional furnace. The plasma-sintered samples exhibit a higher densification rate, smaller grain size and higher compressive strength compared to those of conventional sintered samples. The [Ca2+] concentration and the dissolution rate are also higher than those of conventional sintered samples in physiological saline. After immersed in simulated body fluid (SBF) and simulated inflammation body fluid, the amount of bone-like apatite formed on plasma-sintered samples is more than that formed on conventional sintered samples. The results indicate that plasma sintered porous BCP bioceramics have better mechanical properties and may also have better biological properties. On the other hand, the surface of samples that underwent a simulated inflammation procedure is smoother and the amount of bone-like apatite formed on them is less than that formed on the samples immersed in normal SBF all the time, which may indicate that the light acid in an inflammation response would affect the bone reconstruction when Ca-P bioceramics implanted in living body.

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