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P A Caza

Publications and source records attributed to P A Caza.

6 recordsLinked to original sources
PubMed1984

Short-term exposure to an odor increases its subsequent preference in preweanling rats: a descriptive profile of the phenomenon.

Five experiments assessed the change in preference for an ambient odor after a brief period of exposure to that odor. Three minutes of exposure to a novel odor consistently increased subsequent preference for that odor. This effect occurred in preweanling rats 10 and 15 days of age even though, relative to the nest, the conditions of exposure were probably aversive tactually and thermally. There was relatively little variation in this effect between the ages of 10 Days postnatal and adulthood and over exposure durations ranging between 3 and 81 min. Substantial retention of this exposure effect was found for the 10-day-old rat, with no decline in induced preference over a 24-hr period. The effect was unchanged by brief familiarization with the testing situation, but was eliminated by prior aversive experience with the testing situation. These results have implications for the design and interpretation of experiments that test learning and memory of odors, and emphasize generally the facility of the developing rat for processing olfactory information.

Aging↗
PubMed1984

Noradrenergic influences on blocking: interactions with development.

Two experiments assessed the effects of various noradrenergic agents on selective attention. Selective attention was operationally defined as blocking of a conditioned odor aversion by prior conditioning to spatial cues. In Experiment 1, there was a trend for such blocking to increase developmentally. In addition, the administration of isoproterenol prior to training tended to facilitate the demonstration of blocking in adolescent rats and reduced it in adult subjects. In Experiment 2, administration of yohimbine or propranolol prior to training also reduced blocking in adult subjects; however, the concomitant administration of these two drugs restored blocking in adult rats. These results were interpreted to support a model relating an optimal level of noradrenergic activity in the dorsal bundle and selective attention.

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PubMed1982

Pharmacological manipulation of milk-induced behaviors in three-day-old rat pups.

The effects of a variety of pharmacological agents on the ingestive and behavioral activating responses to intraoral milk infusion were investigated in three-day-old Sprague-Dawley rat pups. Results indicated that the ingestive component--typified by a mouthing response--was primarily influenced by serotonergic agents. Mouthing behavior was increased following administration of the serotonergic agonist, quipazine, and decreased following the serotonergic antagonists, methysergide and methiothepin. In contrast, the behavioral activating component was not found to be clearly influenced by drugs affecting any one neurotransmitter system, suggesting the tentative hypothesis that this activating response to milk infusion may in part be modulated by interactions between several neurotransmitter systems.

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PubMed1980

Ontogenesis of morphine-induced behavior in the rat.

Ten, seventeen and twenty-four day old rats were observed using a behavioral-time sampling procedure following injection of saline, 0.1, 0.5, 1.0 or 5.0 mg/kg/5cc morphine sulphate. At Day 10, the predominant response to morphine was a depression of locomotor activity. At the 5 mg/kg dose, catalepsy was also seen. In animals of this age, 0.1 mg/kg morphine, which was not sufficient to depress activity, also had no effect on stereotyped gnawing/mouthing behavior, nor did it produce any increase in locomotor activity. A morphine-induced increase in locomotion was first seen on Day 17 (after 0.5 mg/kg morphine). As with Day 10 animals, Day 17 animals given 5 mg/kg morphine showed a depression of locomotion and catalepsy. Stereotypic gnawing/mouthing behavior was first seen in Day 24 animals (after 5 mg/kg morphine), although no dose of morphine produced significant differences in activity at this age. Possible mechanisms resulting in these marked alterations in behavioral response patterns to morphine during this two week period of ontogeny are discussed.

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