Gastrointestinal physiology-regulated dogs for bioavailability evaluation of an oral controlled-release dosage form composed of pulsatile release granules.
Biol Pharm Bull
; 19(9): 1184-8, 1996 Sep.
Article
in En
| MEDLINE
| ID: mdl-8889038
ABSTRACT
Gastrointestinal (GI) physiology-regulated beagle dogs (regulated dogs) were regulated by a combined treatment using intramuscular pentagastrin and intravenous atropine sulfate. In the regulated dogs, the gastric pH was shifted to around 2, and the GI transit time was prolonged to approximate that in humans. Pranoprofen, an acidic anti-inflammatory agent, was granulated around sucrose seeds, and then coated with low substituted hydroxypropyl cellulose used as a swelling agent to afford plain granules (A-granule). Then, A-granule was coated stepwise with ethyl cellulose used as an outer shell material to afford two kinds of pulsatile release granules (B- and C-granules). In the dissolution study using pH 1.2 and 6.8 media, A-, B- and C-granules exhibited lag times of 0, 1 and 2h, respectively. Even in intact beagle dogs, the absorption profiles for A- and B-granules corresponded with those expected from the dissolution profiles. In contrast, the bioavailability of C-granule was only 35% in the intact dogs, but was 55% in the regulated dogs. Thus, the absorption of pranoprofen from pulsatile release granules after a longer lag time should be influenced by the location in the GI tract. Next, a controlled-release (CR) dosage form of pranoprofen was tentatively prepared by combining A-, B- and C-granules at the ratio of 343 (w/w in contents of pranoprofen). The bioavailability of the CR dosage form was significantly diminished in the intact dogs, being about 70% as much as that in the regulated dogs. Therefore, the regulated dogs would be superior to the intact dogs in avoiding the underestimation of the bioavailability of a CR dosage form with a pulsatile release property.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pharmacokinetics
/
Biological Availability
/
Delayed-Action Preparations
/
Digestive System Physiological Phenomena
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Biol Pharm Bull
Year:
1996
Document type:
Article