Calcium kinetics in the Solanum malacoxylon-treated rat
Cabrejas, M.; Ladizesky, M.; Mautalen, C.A.
Journal of Nutrition 105(12): 1562-1566
1975
ISSN/ISBN: 0022-3166 PMID: 1195017 Document Number: 93542
Groups of 5 adult rats were given a diet containing 0.5% Ca and 0.4% P with or without daily doses of 500 mg Solanum malacoxylon (SM) leaves as an aqueous extract. After 5 days on the diet animals in both groups were given an intraperitoneal injection of 4 mu Ci 47Ca. Body activity and serum 40Ca and 47Ca activity were estimated at intervals. After 20 days on the diet 24-h samples of urine were collected from each rat and analysed for Ca, creatinine and hydroxyproline. Throughout the experiment serum 40Ca was significantly higher for the SM-treated than for the control animals. After injection of 47Ca its specific activity was similar in both groups for 24 h, thereafter it was significantly lower in the SM-treated group. Body retention of 47Ca was slightly but significantly lower in the SM-treated group 3 h after injection, subsequently the difference became much greater. At the end of the experiment, urinary excretion of Ca and creatinine was higher and of hydroxyproline lower in the SM-treated than in the control rats. It is concluded that, in the rat, SM treatment increases body excretion of 47Ca and decreases the bone accretion rate, by stimulation of bone resorption.