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The regional glucose utilization in the telencephalon of toadsBufo bufo during stimulation with different visual key stimuli was quantitatively mapped by means of the14C-2DG autoradiographic method: (i) a 4×28 mm2 worm-like stripe (W) eliciting prey catching responses, (ii) a 84×84 mm2 square (S) releasing predator avoidance responses, and (iii) a 28×4 mm2 antiwormlike stripe (A) eliciting no motor response.

The (14C)2DG autoradiographic technique has been employed to quantitatively map glucose utilization in the mesencephalon, the diencephalon and the cerebellum, of toads in response to configurational moving visual stimuli: (i) a 0.4 cm × 2.8 cm worm-like stripe (W) which elicited prey catching responses, (ii) a 8.4 cm × 8.4 cm square (S) that released predator avoidance responses, and (iii) a 2.8 cm × 0.4 cm antiworm-like stripe (A) which elicited no motor activity.

Schedules of limited daily access to food result in 'anticipatory' activity preceding each daily feeding. It is well-established that such food-anticipatory activity depends on a food-entrainable circadian timing mechanism. In the present study, we sought to extend the generality of these results by maintaining rats in running wheels under schedules which provided access to salt solutions or to salty food for 2 hr each day. The animals were subjected to dietary, pharmacological and surgical treatments that promote salt appetite. However, we found no evidence for daily salt-anticipatory wheel running activity in any condition.

Summary.Twenty female rats were implanted with myometrial electrodes and intrauterine balloons to study the effects of mating on uterine contractile activity. Mating produced both immediate and delayed effects. Uterine activity typically doubled during the period of active mating (the immediate effect), then briefly returned to the premating activity level after ejaculation. Beginning 5 min after the ejaculation, the delayed effect of mating was observed: contractile activity increased when the baseline activity had been low, but decreased when baseline was fast. This delayed effect lasted for 30 min to several hours. Vaginocervical stimulation seemed to play a critical role in these responses: artificial vaginocervical stimulation mimicked the response while vigorous mounting by males that were prevented from intromitting did not evoke these responses. Vaginocervical stimulation, whether mating-derived or experimenter-delivered, produced immediate and delayed effects on uterine contraction rate.

Summary.The role of accumulated intrauterine fluid in rats at oestrus was investigated by experimentally altering the fluid volume in 106 rats. Complete evacuation of uterine fluid or low natural fluid volume did not significantly reduce the number of embryos on Day 10 of pregnancy overall. Transuterine (but not transcervical) sperm transport was reduced by uterine fluid removal, but did not vary significantly with naturally occurring variations in fluid content. Irrespective of fluid content, transuterine sperm transport was, on average, greater in right than left horns. Distensible balloons inserted into the uterus indicated that increasing and decreasing volume increased and decreased respectively myometrial activity at oestrus and dioestrus. Left horns contracted less frequently than did right horns at low volumes. While uterine fluid volume clearly affected uterine contractility and transuterine sperm transport, we were unable to demonstrate a major role of fluid for fertility.