In this study normal and acid-treated powdered date pits were added to the feed of male rats at concentrations of 7 and 14% for 28 consecutive days. The body weight of rats, their feed and water intake, and urine and faecal output were monitored daily. At the end of the trial period, blood plasma was analysed for testosterone, oestradiol and luteinizing hormone (LH) concentrations, and for some indicators of hepatic and renal functions. Sections from some vital organs (liver, kidney, heart, lung, spleen and testes) were histologically examined. The results indicated that treatment with normal date pits (14%) significantly increased the body weight of rats (p < 0.05). The other treatments did not significantly affect the body weight. At concentrations of 7 and 14%, the normal date pits significantly increased the concentration of testosterone in plasma (p < 0.05), while the acid-treated date pits (14%) slightly but significantly increased the concentration of LH. Plasma oestradiol concentration and the other measured variables were not affected by any of the treatments. Treatment of female rats for 10 days with a lyophilized extract of date pits, or with a polar or non-polar fraction prepared from it, at oral and intraperitoneal doses of 500 mg kg(-1), did not significantly affect the body or uterine weights, nor did it affect the degree of vaginal orifice opening. Oestradiol (2 mg kg(-1), subcutaneously) increased uterine weight and degree of vaginal orifice opening. Compared to the control, the lyophilized extract and the polar fraction significantly reduced plasma oestradiol concentration by about 25 and 36%, respectively. The non-polar fraction, however, increased the hormone level by about 12%, but this was not significant. (C) 1999 Elsevier Science Ltd. All rights reserved.
