Effect of porcine follicular fluid on the postcastration secretion of gonadotropins in rhesus monkeys

Porcine follicular fluid (pFF) contains a nonsteroidal factor(s) that modifies pituitary secretion of both FSH and LH under certain physiological and experimental conditions. The aim of this study was to further define the activity of pFF on basal and pulsatile gonadotropin secretion after bilateral oophorectomy in monkeys. Sexually mature female rhesus monkeys underwent bilateral oophorectomy during the early follicular phase of the menstrual cycle. For 10 consecutive days, beginning on the day of surgery, monkeys were given twice daily sc injections of 2.5 ml normal saline (group I, control; n = 3), 2.5 ml steroid-free pFF (group II; n = 3), or 5.0 ml steroid-free pFF (group III; n = 3). Blood was drawn daily for 32 days, beginning the day before castration. One day before and on days 6 and 20 after castration, monkeys were placed in a restraining chair, and blood samples were drawn every 15 min for 6 h via an indwelling venous catheter. All samples were radioimmunoassayed for FSH and LH. In group I, a significant increase in serum FSH and LH occurred on days 3 and 6 postcastration, respectively. A significant increase in serum FSH did not occur until day 13 postcastration in groups II and III. Serum LH was significantly increased on days 10 and 9 postcastration in groups II and III, respectively. The LH pulse frequency ranged from 60-105 min and did not change after castration in control or pFF-treated animals. The LH pulse increment was significantly increased on day 6 postcastration in group I, but not until day 20 postcastration in groups II and III. Only minor oscillations in FSH were found until day 20 postcastration, at which time there was no significant difference in FSH pulse frequency or increment among groups. These findings demonstrate that a nonsteroidal factor(s) in pFF suppresses basal FSH and LH concentrations and LH pulse increment in monkeys after surgical castration. Further, because LH, but not FSH, concentrations began to increase during pFF treatments, these data suggest a temporal disparity in the effects of pFF on FSH and LH secretory profiles.     

ICRF-159 enhancement of radiation response in combined modality therapies. II. Differential responses of tumour and normal tissues.

The combined effect of the chemotherapeutic agent ICRF-159 and radiation on the proliferative status of tumor/normal systems has been evaluated using the Lewis lung tumour in BDF1 mice. We have previously shown that a 25 mg/kg dose of ICRF-159, given at 3h intervals X4 before irradiation, significantly enhanced tumour growth retardation relative to a single dose of 100 mg/kg before irradiation. Whilst both single and fractionated drug treatments produced a transient inhibition of cell proliferation, comparisons of the temporal recovery from the antiproliferative effect of radiation in both tumour and intestinal epithelium suggested that single acute doses of ICRF-159 fail to potentiate the radiation response of either tissue. Protracted drug administration before irradiation, however, markedly decreases the post-radiation proliferative recovery of the tumour, without significantly altering intestinal recovery. The data suggest that both drug concentration and/or exposure time determine the interactions seen with combined modes.     

Time/dose relationships in experimental radiation cataractogenesis.

The response of the mammalian lens to fractionated radiation exposures was evaluated as a model system for predicting delayed radiation effects on normal tissue. Only the heads of male Ha/ICR mice were irradiated with 14 different time-dose schedules and followed for cataractous changes. A log-log plot of dose vs time yielded a line with a slope of 0.303 and ordinate intercept of 1050 R; a similar plot for dose vs fraction number yielded a slope of 0.382 and ordinate intercept of 835 R. Results suggest that the lenticular response to radiation may be a useful model for studying late effects.     

Renal and haemopoietic proliferative defects as a delayed consequence of cis-platin, adriamycin and daunomycin treatments.

The long-term effects of Adriamycin (ADR), daunomycin (DMN) and cis-dichlorodiammine platinum (II) (DDP) on the ability of murine renal tubular epithelium and erythropoiesis to respond to an acute proliferative stress was investigated. Folic acid (FA) and acute anaemia induced by bleeding were used as acute proliferative stimuli for renal-tubule epithelium and erythropoiesis respectively. The ability of these normal cell-renewal systems to mount a regenerative proliferative response was evaluated by radioisotopic, morphological and gravimetric techniques 4 months after drug treatment. The results indicate that pretreatment with these agents produce a long-lasting reduction in the ability of these cell-renewal systems to mount regenerative proliferation. In the kidney, the ability to respond to FA was most severely compromised by ADR and DDP, whereas in the erythropoietic system all 3 agents induced a long-lasting proliferative defect.     

Endosurgical electrocoagulation of the mesovarium as an alternative method of inducing surgical menopause in monkeys

This study in the primate demonstrates that electrocoagulation of the mesovarium under endoscopic visualization could successfully replace conventional surgical excision of the ovary.     

Human chorionic gonadotropin and steroid concentrations in human follicular fluid in relation to follicle size and oocyte maturity in stimulated ovarian cycles

The concentrations in follicular fluid (FF) of beta hCG, progesterone (P), estradiol (E2), androstenedione (A) and testosterone (T) by RIA were determined, in order to study the follicular micro-environment in stimulated cycles. Patients received either clomiphene with hMG plus hCG or hMG plus hCG. With increasing volume of FF (obtained at laparoscopy), P significantly increased (p less than 0.04) and hCG (p less than 0.0004) and T (p less than 0.05) significantly decreased with a borderline decrease in A (p less than 0.07). Progesterone also increased with advancing oocyte maturity. Beta-hCG and P were positively correlated with E2 and negatively correlated with A levels. It is suggested that FF hCG and progesterone levels may be markers of follicular development in stimulated cycles.