Jef Roos

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In 12-19 weeks old human fetuses, LHRH-immunoreactive (LHRH-Ir) cells were detected in the nerve fascicles arising from the vomeronasal organ (VNO), from their origin to their end point at the medial aspect of the olfactory bulb (vomeronasal and/or terminal nerves). In one 22-weeks-old fetus, LHRH-Ir cells were present only in the upper part of the nasal(More)
Orchidectomized rats were given estrogen and progesterone and tested for feminine behavior in the presence of a mounting male after accessory olfactory bulb removal (AOBR). Complete AOBR caused a rise in the number of estrogen-progesterone-treated male rats responding by lordosis behavior to male mounts as compared to controls and sham-operated animals. By(More)
The aim of this investigation was 1) to compare the development of AOB in male and female rats before birth, early after birth, and at later stages of sexual immaturity and maturity 2) to examine the effects of early and delayed castration after birth on AOB development in the male rat. A significant increase of the surface area of AOB was observed in both(More)
The aim of this study was to investigate the olfactory mechanisms regulating the display of lordosis behavior in intact Wistar male rats bred in our colony. Gonadally intact males show a low capacity to respond by lordosis to male mounts and were insensitive to manipulations of the olfactory system (exposure to the odor of male urine or accessory bulb(More)
The effects of androgen treatment (TP) from postnatal day 20 (P20) onwards on the accessory olfactory bulbs' (AOB) development were studied in rats orchidectomized at birth (PO) or on P20. TP failed to restore impaired AOB development in the rats castrated at PO but completely restored AOB development in those castrated at P20. Androgen secretion during(More)
The aim of this study was to investigate the mechanisms of the stress-related ovulatory effects of unilateral ovariectomy (ULO) when performed on diestrus III at 10.00-11.00 hr in 5-day cyclic female rats. Ovulation evoked by ULO was suppressed in adrenalectomized rats. An increase in blood progesterone within 1 hour after ULO was observed in non(More)
A significant decrease in early receptivity during the night from dioestrus II to prooestrus was observed in estrogen-treated 4-day cyclic rats following bilateral ovariectomy on dioestrus II at 4-5 p.m. Early receptivity appeared then to be dependent on the presence of ovary at this stage of the cycle. The mechanism whereby the adrenals may compensate for(More)
The luteinizing action of oestradiol benzoate (OB) has been studied in 4-day cyclic female Wistar rats submitted to a dose of 10 mug on the morning of dioestrus I at 10-11 a.m. In a first experimental series a blockage of luteinization was observed in females injected with pentobarbital (PB) either on dioestrus I at 11 a.m. and 5 p.m. respectively or on(More)
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