• YAKHAK HOEJI
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• v.42 no.2
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• pp.196-204
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• 1998

The blood-brain barrier (BBB) of rats was modificated opening reversibly by infusing a hyperosmotic solution of arabinose (1.6 molal) into the right external carotid artery. Pre vious studies demonstrated that permeability was increased maxmmally in the first 15 min and remained slightly elevated at 1 hr. As control reference, saline was used. In the present study, to evaluate the effects of osmotic BBB opening on the BBB trasport according to hydrophilic or hydrophobic characteristics of drugs. And the differences of the uptakes of these compounds to right (treated osmotic opening) and left (untreated) hemispheres in same rats were compared each other following injection of 8 mCi per rat of $^{99m}Tc$-ethylene triamine pentaacetic acid (DTPA) as hydrophilic drug or 5mg/kg of phenytoin as hydrophobic drug mto the right external carotid artery of rats between two groups (1.6 molal arabinose vs saline). The uptakes of $^{99m}Tc$-DTPA and phenytoin in the right cerebral hemispheres were increased to about thirty three times and twice rather than those in the left cerebral heimspheres, respectively. And PAs (permeability X capillary surface area) were also increased from a control mean of 2.11${\times}10^{-4}$ (Untreated) to 6.98${\times}10^{-3}\;sec^{-1}$ (treated osmotic opening for $^{99m}Tc$-DTPA and 0.29 to 0.17 $sec^{-1}$ for phenytoin, respectively. From the results of present study, it is noted that osmotic opening of BBB is more effective in the brain delivery of hydrophilic drugs rather than that of hydrophobic drugs.

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.622-634
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• 1993

Gingiva is remarkly sensitive to certain drugs. Especially, long term use of phentoin, dihydropyrydine (including nifedipine), cyclosporin and other drugs can be lead to pathologic changes in gingival tissue, especially in terms of proliferation of epithelium and connective tissue. Recent study in terms of proliferation of epithelium and connective tissue. Recent study is focused on the inhibition of drug-induced gingival hyperplasia by using medicaments. The purpose of this study was to investigate on the pharmacological effects of nifedipine, retinoic acid and glycyrrhetini acid to the activity in human gingival fibroblast. Human gingival fibroblasts were cultured from the healthy gingiva of orthodontic patients. Gingival fibroblasts were trypsinized and cultured in growth medium added $5{\mu}g/ml$ of nifedipine, $10^{+7}M$ of retinoic acid and glycyrrhetinic acid. The passage number of cultured fibroblasts were between fifth and eighth. The cell morphology was examined by inverted microscope and the cell acitivity was measured by the MTT assay. Nifedipine at the concentration of $5{\mu}g/ml$ was revealed significantly effective to increase the cell activity and lipopolysaccharide was cofactor to increase cell activity in the presence of nifedipine. However, retinoic acid was significantly effective on the globular change of cell morphology and loss of cell process regardless of the presence of nifedipine and LPS. Cell activity was significantly decreased by the glycyrrhetinic acid at the concentration of $10^-M$ regardless of the presence of nifedipine and LPS. These results suggested that the increased cell activity by nifedipine might be modulated by retinoic acid and glycyrrhetinic acid. Further study is needed to clarify on their toxicological effects during cellular modulation and mRNA expression change.