![]() |
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
ABSORPTION, DISTRIBUTION, METABOLISM, AND EXCRETION
Department of Pharmacy, Kyoto University Hospital, Faculty of Medicine, Kyoto University, Kyoto, Japan
We previously demonstrated that H+/peptide cotransporter PEPT1 shows a diurnal rhythm in the rat small intestine. In the present study, we examined the effect of food intake on the diurnal rhythm of intestinal PEPT1 using fed and fasted rats and also determined whether such variation affected the pharmacokinetics of peptide-like drugs. In fed rats, PEPT1 protein level was significantly higher at 8:00 PM than at 8:00 AM. However, during fasting for 2 to 4 days, the differences of PEPT1 protein levels between 8:00 AM and 8:00 PM gradually disappeared. Intestinal absorption of an oral antibiotic ceftibuten (CETB), a pharmacological substrate for PEPT1, was also greater at 8:00 PM than at 8:00 AM in fed rats, but not different in 4-day fasted rats. In contrast to PEPT1 protein levels, PEPT1 mRNA levels retained a diurnal rhythm after 4 days of fasting. Pharmacokinetic analyses of CETB after intraintestinal administration demonstrated that both Cmax and area under the plasma concentration-time curve from 0 to 3 h were greater at 8:00 PM than at 8:00 AM in fed rats. In contrast, pharmacokinetic parameters showed no significant difference between 8:00 AM and 8:00 PM for intraintestinal administration in 4-day fasted rats and for intravenous administration in fed and 4-day fasted rats. These findings suggested that the diurnal rhythm of intestinal PEPT1 transport activity was disrupted by fasting and that diurnal variation of intestinal PEPT1 functionality could influence the pharmacokinetics of peptide-like drugs such as CETB.
Address correspondence to: Professor Ken-ichi Inui, Department of Pharmacy, Kyoto University Hospital, Sakyo-ku, Kyoto 606-8507, Japan. E-mail: inui{at}kuhp.kyoto-u.ac.jp
This article has been cited by other articles:
![]() |
E. R. Gilbert, E. A. Wong, and K. E. Webb Jr. BOARD-INVITED REVIEW: Peptide absorption and utilization: Implications for animal nutrition and health J Anim Sci, September 1, 2008; 86(9): 2135 - 2155. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Saito, T. Terada, J. Shimakura, T. Katsura, and K.-i. Inui Regulatory mechanism governing the diurnal rhythm of intestinal H+/peptide cotransporter 1 (PEPT1) Am J Physiol Gastrointest Liver Physiol, August 1, 2008; 295(2): G395 - G402. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Chen, T. Terada, K. Ogasawara, T. Katsura, and K.-i. Inui Adaptive responses of renal organic anion transporter 3 (OAT3) during cholestasis Am J Physiol Renal Physiol, July 1, 2008; 295(1): F247 - F252. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Pan and M. M. Hussain Diurnal Regulation of Microsomal Triglyceride Transfer Protein and Plasma Lipid Levels J. Biol. Chem., August 24, 2007; 282(34): 24707 - 24719. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Shimakura, T. Terada, H. Saito, T. Katsura, and K.-i. Inui Induction of intestinal peptide transporter 1 expression during fasting is mediated via peroxisome proliferator-activated receptor {alpha} Am J Physiol Gastrointest Liver Physiol, November 1, 2006; 291(5): G851 - G856. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Tsuda, T. Terada, M. Irie, T. Katsura, A. Niida, K. Tomita, N. Fujii, and K.-i. Inui Transport Characteristics of a Novel Peptide Transporter 1 Substrate, Antihypotensive Drug Midodrine, and Its Amino Acid Derivatives J. Pharmacol. Exp. Ther., July 1, 2006; 318(1): 455 - 460. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Gaildrat, M. Moller, S. Mukda, A. Humphries, D. A. Carter, V. Ganapathy, and D. C. Klein A Novel Pineal-specific Product of the Oligopeptide Transporter PepT1 Gene: CIRCADIAN EXPRESSION MEDIATED BY cAMP ACTIVATION OF AN INTRONIC PROMOTER J. Biol. Chem., April 29, 2005; 280(17): 16851 - 16860. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Shimizu, S. Masuda, K. Nishihara, L. Ji, M. Okuda, and K.-i. Inui Increased protein level of PEPT1 intestinal H+-peptide cotransporter upregulates absorption of glycylsarcosine and ceftibuten in 5/6 nephrectomized rats Am J Physiol Gastrointest Liver Physiol, April 1, 2005; 288(4): G664 - G670. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Pan, T. Terada, M. Okuda, and K.-I. Inui The Diurnal Rhythm of the Intestinal Transporters SGLT1 and PEPT1 Is Regulated by the Feeding Conditions in Rats J. Nutr., September 1, 2004; 134(9): 2211 - 2215. [Abstract] [Full Text] [PDF] |
||||