Cytoprotective Effect of R,â-Unsaturated Carbonyls
J ournal of Medicinal Chemistry, 1997, Vol. 40, No. 12 1833
in this study were prepared just before the experiment as
follows: Compounds 1-23 were suspended in water. The
control rats (group 1) were given 1 mL of absolute EtOH.
Compounds 1-23 (40 mg/kg) were given 1 h before oral
administration of EtOH (group 2).
Ack n ow led gm en t. We would like to thank Dr. J .
Guzma´n for providing the biological data. This work
was supported by UNSL and CONICET (Argentina).
F igu r e 7. Schematic view of a triple overlap among three
coplanar spheres. This figure shows the intersection area S∆.
Su p p or tin g In for m a tion Ava ila ble: VWMS calcula-
tional method (13 pages). Ordering information is given on
any current masthead page.
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F igu r e 8. Schematic view showing the overlap between two
spheres. θ0 is the angle determined by the segment S0S1 and
the S0 center with a point of the intersection circumference.
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cases in which two helmets overlap (like, for example, b01 and
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intersection area S∆ from the equation previously reported by
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S0(acc) ) S0 - b01 - b02 + S∆
2. Ca lcu la tin g Volu m es. In order to evaluate the free
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Vbound ) (V0 + V1 )/2
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where each volume is evaluated with the equation
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3
V0(free) ) 4/3πR0 - Vbound
3
V1(free) ) 4/3πR1 - Vbound
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In d u ction of Ga str ic Lesion s. Gastric lesions were
produced according to the method of Robert et al.4 Male
Wistar rats weighing ca. 180 g were fasted for 24 h and
deprived of water for 19 h prior to the experiments. All rats
were housed in wire mesh-bottom cages throughout the study
to prevent coprophagy. Absolute EtOH (1 mL) administered
orally was employed as the necrotizing agent, and 1 h later
the animals were decapited. The stomachs were removed,
opened along the greater curvature, and washed gently with
ice-cold saline solution. The degree of erosion in the glandular
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2, more than 3 small erosions or 1 large erosion; 3, 1 large
erosion and more than 3 small erosions; 4, 3-4 large erosions;
5, any very large erosion or ulcer perforation.
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The results are expressed in terms of an ulcer factor which
is the average severity of erosions per rat for each group on
the scale from 0 to 5. The sum of these values was divided by
the number of animals. The control rats treated with absolute
EtOH showed an average score of 4.8. The control rats without
treatment showed an average score of 0.0. The drugs tested
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