Physiology of the colorectal barrier

doi:10.1016/S0169-409X(97)00071-9

Advanced Drug Delivery Reviews

Volume 28, Issue 2, 10 November 1997, Pages 173-190

https://doi.org/10.1016/S0169-409X(97)00071-9 Get rights and content

Abstract

The colon is a suitable site for the safe and slow absorption of drugs which are targetted at the large intestine or designed to act sytemically. The physiology of the colorectal barrier is complex and influenced by many factors including diet, bacterial metabolism and colonic mixing and transit time. As the motility and absorption characteristics of the colon change from the proximal colon to the rectum, the physiology of these regions and the likely residence time of any drug at each site must be understood for the full potential of the colon to be exploited. This article will discuss the main physiological factors affecting the colon and hence colonic drug absorption.

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Physiology of the colorectal barrier

Abstract

Gastroenterology

Gastroenterology

Gastroenterology

Gastroenterology

Gastroenterology

Gastroenterology

Comp. Biochem. Physiol.

Gastroenterology

Gastroenterology

Gastroenterology

Gastroenterology

Biochim. Biophys. Acta

Mutat. Res.

Mutat. Res.

Gastroenterology

Drug delivery to the proximal colon

J. Pharm. Pharmacol.

Retrograde spread of hydrocortisone containing foam given intrarectally in ulcerative colitis

Br. Med. J.

Comparative physiology of the digestive system

Colonic motility in the cat. II Extrinsic nervous control

Acta Physiol. Scand.

Extrinsic nervous control of colonic motility and blood flow. An experimental study in the cat

Acta Physiol. Scand.

The intramural pelvic nerves in the colon of dogs

J. Physiol.

Regional cholinergic differences between distal and proximal colonic myenteric plexus

Am. J. Physiol.

Physiology and pathohysiology of colonic motor activity

Dig. Dis. Sci.

Regulation of colonic blood flow

Capillary blood flow in the canine colon and other organs at normal and raised portal pressure

Gut

Vascular responses to mechanical stimulation of the mucosa of the cat colon

Acta Physiol. Scand.

Short chain fatty acids dilate isolated human colonic resistance arteries

Gut

Intestinal blood flow und motility

Glucose coupled sodium absorption in the developing rat colon

Am. J. Physiol.

Age reluted loss of non-goblet cells parallels decreased secretion in rat descending colon

Am. J. Physiol.

Crypt cell production rate at various sites around the colon in Wistar rats and humans

Gut

The effect of dietary fibre content of lifelong diet on colonic cellular proliferation in the rat

Gut

Capacity of the human colon to absorb fluid

Gastroenterology

Maximal capacity for fluid absorption in human bowel

Dig. Dis. Sci.

Water and salt absorption in the human colon

J. Clin. Invest.

Regional differences in rates of absorption of sodium and water from the human large intestine

Can. J. Physiol. Pharmaeol.

Differences in electrolyte handling through the human large intestine

Electrophysiology of the human colon: evidence of segmental heterogeneity

Gut

Ion transport in proximal colon of the rat. Sodium depletion stimulates neutral sodium chloride absorption

J. Clin. Invest.

Ion transport in rat proximal colon in vivo

Am. J. Physiol.

Characterisation of an apical sodium conductance in rabbit cecum

Am. J. Physiol.

Mechanism of active potassium absorption and secretion in the rat colon

Am. J. Physiol.

Active potassium concentration at the mucosal surface of the proximal and distal colon of the guinea pig

Gut

Mechanism and regulation of transcellular potassium transport by the colon

Am. J. Physiol.

Active K+ transport across rabbit distal colon relation to Na absorption and CL secretion

Am. J. Physiol.

Acid secretion in isolated guinea pig colon

Am. J. Physiol.

Active potassium absoprtion in rat distal colon

J. Physiol.

K+ Transport in isolated guinea pig colonocytes: evidence for Na+ independent ouabain-sensitive K+ pump

Am. J. Physiol.

Potassium microclimate at the mucosal surface of the proximal and distal colon of the guinea pig

Active K⁺ transport across rabbit distal colon relation to Na absorption and CL secretion

K⁺ Transport in isolated guinea pig colonocytes: evidence for Na⁺ independent ouabain-sensitive K⁺ pump