Use of tamoxifen, an antioestrogen, in establishing a need for oestrogen in early pregnancy in the bonnet monkey (Macaca radiata)

Administration of tamoxifen orally (3 mg/kg/day) during the post-ovulatory period from Days 16 to 20 or from Days 18 to 30 of female bonnet monkeys mated between Days 9 and 14 of the cycle resulted in inhibition of pregnancy establishment in 90-100% of monkeys tested. The pregnancy establishment in control female monkeys after exposure to the male during one ovulatory cycle was 66%. The effect of tamoxifen was not due to interference with luteal function because there was no reduction in serum progesterone concentrations after drug treatment. Exogenously administered progesterone could not reverse the inhibitory effect of tamoxifen on pregnancy establishment. The effect of tamoxifen was dose-dependent. We suggest that tamoxifen could be developed as an effective post-ovulatory contraceptive for regulation of female fertility

Antifertility effect of tamoxifen as tested in the female bonnet monkey (Macaca radiata)

The administration of a potent antiestrogen, tamoxifen at a dose of 3 mg/kg body weight/day orally post-coitally to cycling mated bonnet monkeys(Macaca radiata) from days 18-30 of cycle resulted in inhibition of establishment of pregnancy in 9 out of 10 monkeys. Tamoxifen effect was not due to interference with luteal function. The effect was specific to tamoxifen as exogenously administered progesterone could not reverse it. In addition to suggesting a role for estrogen in maintenance of early pregnancy in the primate the present study could be a prelude to the development of an effective post-ovulatory approach for regulation of fertility in the human female

Bilateral renal angiomyolipomas with invasion of the renal vein: A case report

An angiomyolipoma (AML) is usually a benign, rare, and, more commonly, a unilateral renal tumour. Bilateral tumours are very rare, particularly in the absence of tuberous sclerosis complex. Only in a few isolated cases have features of malignancy been associated with an AML. We present a unique case of bilateral AMLs mimicking invasive tumours in the absence of any other features of tuberous sclerosis complex

Depletion of glutathione and enhanced lipid peroxidation in the CSF of acute psychotics following haloperidol administration

Haloperidol administration for 2 weeks results in significant reduction in the concentration of GSH in the CSF. Concomitantly, the levels of lipid peroxidation products increased as evidenced by increased malondialdehyde levels. The malondialdehyde levels in the CSF prior to haloparidol administration were not significantly higher than that seen in CSF from normal controls (data not shown) suggesting that increased oxidative stress did not exist in these patients prior to haloperidol administration. All the patients included in the present study were drug naive and hence the changes observed in the glutathione and malon6ialdehyde levels in the CSF were indeed mediated by haloperidol administration. The only other medication that was administered namely, anticholinergic drug, trihexyphenidyl is not known to cause any oxidative stress. The present study thus demonsuates that haloperidol administration results in significant oxidative stress. The generation of the oxidative stress is probably due to the increased turnover of dopemine caused by typical neuroleptics. Increased dopamine turnover is also observed in Parkinson's disease and the combination therapy consisting of antioxidant vitamin E and monoamine oxidase inhibitor, deprenyl has been shown to offer limited protection against the progression of the disease (Parkinson Disease Study Group 1989). In the present study, all the 15 patients exhibited extrapyramidal symptoms although the time of onset, the duration and the severity of the side effects differed between patients. On the presumption that the oxidative stress generated by haloperidel may cause extrapyramidal symptoms, the present study in humans taken together with the evidence provided in our earlier studies on rats (Shivakumar and Ravindranath 1992,1993) may justify experimental coadministration of antioxidanls (e.g., vitamin E) with typical neuroleptics like haloperidol to prevent the acute side effects

Growth and reproductive parameters of bonnet monkey (Macaca radiata)

The present paper summarizes some of the important biological and physiological data recorded over a 30-year period on the biology of bonnet monkeys in captivity. Data on sexual maturity, menstrual cyclicity, general behaviour, endocrine profile, reproductive physiology, gestation, parturition, postpartum amenorrhoea in the female, and sexual maturity, hormone profile, and seasonal variation in sperm count of the male monkeys are presented. In addition to the biological values, weights of selected organs, vertebral and dental pattern are also presented. Menarche occurred at an age of 36±4 months and the first conception in the colony occurred at an age of 54±4 months. The average menstrual cycle length was 28±4.3 days. Majority of monkeys did not cycle regularly during March-June during which the temperature reached a peak. The pregnancy index of the colony was 80% with controlled breeding. The gestation period was 166±5 days with 6-7 months postpartum amenorrhoea. Males attained sexual maturity by the age of 6-7 years and exhibited the characteristic nocturnal surge of serum testosterone at this age and sperm concentration ranged from 116-799 millions/ejaculate

Chemical Radioprotectors

Protection of biological systems against radiation damage is of paramount importance during accidental and unavoidable exposure to radiation. Several physico-chemical and biological factors collectively contribute to the damage caused by radiation and are, therefore, targets for developing radioprotectors. Work on the development of chemicals capable of protecting biological systemsfrom radiation damage was initiated nearly six decades ago with cysteine being the first molecule to be reported. Chemicals capable of scavenging free radicals, inducing oxygen depletion,antioxidants and modulators of immune response have been some of the radioprotectors extensively investigated with limited success. Mechanism of action of some chemical radioprotectors and their combinations have been elucidated, while further understanding is required in many instances. The present review elaborates on structure-activity relationship of some of the chemical radioprotectors, their evaluation, and assessment, limitation, and future prospects