Absorption Mechanism of a Physical Complex of Monomeric Insulin and Deoxycholyl-l-lysyl-methylester in the Small Intestine

Our aim was to investigate the uptake kinetics of forsythin in the small intestine and analyze the factors that affect absorption. Methods. A simple and convenient method was established by HPLC to detect forsythin. To characterize forsythin uptake kinetics in different sacs, three different forsythin concentrations, P-glycoprotein inhibitor verapamil hydrochloride and Tween-80 were assayed by the everted rat gut sac model. Results. Forsythin could be absorbed in the whole intestine, the data had concentration and time dependence, and ka had no significant differences (P>0.05) at three concentrations (10, 20, and 40μg*mL-1). The results showed linear correlation between the forsythin absorption in sac contents and the incubation time from 0~90min. Forsythin absorbed dose order in rat small intestine is ileum>jejunum>duodenum. The permeability increased when forsythin was perfused with Tween-80, but P-gp inhibitor verapamil hydrochloride didn't has this effect. Conclusion. The absorption of forsythin in the small intestine is first-order process. The absorption mechanism is inferred the passive diffusion. Forsythin is not the substrate of P-gp.

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Intestinal absorption mechanism of amino-.BETA.-lactam antibiotics. III. Kinetics of carrier-mediated transport across the rat small intestine in situ.

Journal of Pharmacobio-Dynamics ◽

10.1248/bpb1978.7.452 ◽

1984 ◽

Vol 7 (7) ◽

pp. 452-464 ◽

Cited By ~ 49

Author(s):

EMI NAKASHIMA ◽

AKIRA TSUJI ◽

SEIYA KAGATANI ◽

TSUKINAKA YAMANA

Keyword(s):

Small Intestine ◽

Intestinal Absorption ◽

Rat Small Intestine ◽

Beta Lactam ◽

Absorption Mechanism ◽

Beta Lactam Antibiotics ◽

Carrier Mediated Transport ◽

Kinetics Of

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Identification of Mechanism and Pathway of the Interaction between the African Traditional Medicine, Sutherlandia Frutescens, and the Antiretroviral Protease Inhibitor, Atazanavir, in Human Subjects Using Population Pharmacokinetic (PK) Analysis

Journal of Pharmacy & Pharmaceutical Sciences ◽

10.18433/jpps30068 ◽

2018 ◽

Vol 21 (1s) ◽

pp. 215s-221s ◽

Cited By ~ 1

Author(s):

Adrienne Carmel Muller ◽

Murray P Ducharme ◽

Isadore Kanfer

Keyword(s):

Small Intestine ◽

Protease Inhibitor ◽

Human Subjects ◽

Compartmental Analysis ◽

Compartment Model ◽

Population Pharmacokinetic ◽

Absorption Mechanism ◽

Population Pk ◽

Before And After ◽

Sutherlandia Frutescens

Although the use of the indigenous Southern African plant, Sutherlandia frutescens (SF) for the treatment of HIV/AIDS has previously been described, the risk which it may pose to the safety and efficacy of ARVs and the potential mechanisms which underlie such effects may have clinical significance and relevance. The protease inhibitor (PI), atazanavir (ATV) is a substrate of the efflux transporter, P-gp which modulates absorption in the small intestine, as well as CYP3A4 and CYP3A5enzymes which facilitate metabolism in the small intestine and liver. The objective of this study was to investigate the effect of SF on the pharmacokinetics (PK) of atazanavir (ATV) and to use a population PK analysis to fit and explain plasma concentration vs. time profiles of ATV generated in a previously conducted study in healthy male subjects in order to understand and postulate on the potential mechanism(s) of the drug-drug interaction. The population PK Compartmental Analysis of ATV before and after a two-week regimen of Phyto Nova Sutherlandia SU1 tablets which contain SF plant material indicated that a two compartment model with a dual absorption mechanism best explained the data. The dual absorption mechanism is hypothesized to reflect “passive” (first-order, Ka parameter) and “active” (zero-order, K0 parameter) absorption processes. The model suggested that the mechanism by which SF reduced the overall bioavailability of ATV may be modulated via the inhibition of the “active” absorption process. This study has highlighted the utility of population PK analyses in postulating probable mechanism(s) whereby an ATM or a herbal medicine interacts with an allopathic drug.

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Circadian Rhythmicity of Glycyl-L-leucine Absorption Mechanism in Rat Small Intestine

Agricultural and Biological Chemistry ◽

10.1080/00021369.1981.10864723 ◽

1981 ◽

Vol 45 (6) ◽

pp. 1393-1401

Author(s):

Kyoden Yasumoto ◽

Kimio Sugiyama

Keyword(s):

Small Intestine ◽

Circadian Rhythmicity ◽

Rat Small Intestine ◽

Absorption Mechanism

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Intestinal absorption mechanism of amphoteric β-lactam antibiotics I: Comparative absorption and evidence for saturable transport of amino-β-iactam antibiotics by in situ rat small intestine

Journal of Pharmaceutical Sciences ◽

10.1002/jps.2600700714 ◽

1981 ◽

Vol 70 (7) ◽

pp. 768-772 ◽

Cited By ~ 41

Author(s):

Emi Nakashima ◽

Izumi Kagami ◽

Akira Tsuji ◽

Tsukinaka Yamana

Keyword(s):

Small Intestine ◽

Intestinal Absorption ◽

Rat Small Intestine ◽

Absorption Mechanism

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Electron probe x-ray microanalysis and electron microscopy of amino acid absorption and transport by the small intestine: inhibition by chemical poisons and correlation to the elemental composition of the epithelial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142311 ◽

1986 ◽

Vol 44 ◽

pp. 134-135

Author(s):

A. J. Tousimis

Keyword(s):

Small Intestine ◽

Amino Acid ◽

Epithelial Cells ◽

Elemental Composition ◽

Isotope Labeling ◽

Structural Components ◽

X Ray ◽

Human Small Intestine ◽

Transport Studies

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

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The protease phenotype and crystalline nature of the granules of intraepithelial mast cells in Trichinella spiralis-infected mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140464 ◽

1995 ◽

Vol 53 ◽

pp. 818-819

Author(s):

D.S. Friend ◽

N. Ghildyal ◽

M.F. Gurish ◽

K.F. Austen ◽

R.L. Stevens

Keyword(s):

Small Intestine ◽

Mast Cells ◽

Epithelial Cells ◽

Lamina Propria ◽

Trichinella Spiralis ◽

Intestinal Epithelial ◽

Carboxypeptidase A ◽

C3h Mice ◽

Granule Morphology ◽

Crystalline Nature

Trichinella spiralis induces a profound mastocytosis and eosinophilia in the small intestine of the infected mouse. Mouse mast cells (MC) store in their granules various combinations of at least five chymotryptic chymases [designated mouse MC protease (mMCP) 1 to 5], two tryptic proteases designated mMCP-6 and mMCP-7 and an exopeptidase, carboxypeptidase A (mMC-CPA). Using antipeptide, protease -specific antibodies to these MC granule proteases, immunohistochemistry was done to determine the distribution, number and protease phenotype of the MCs in the small intestine and spleen 10 to >60 days after Trichinella infection of BALB/c and C3H mice. TEM was performed to evaluate the granule morphology of the MCs between intestinal epithelial cells and in the lamina propria (mucosal MCs) and in the submucosa, muscle and serosa of the intestine (submucosal MCs).As noted in the table below, the number of submucosal MCs remained constant throughout the study. In contrast, on day 14, the number of MCs in the mucosa increased ~25 fold. Increased numbers of MCs were observed between epithelial cells in the mucosal crypts, in the lamina propria and to a lesser extent, between epithelial cells of the intestinal villi.

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