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A R Caggiula

Publications and source records attributed to A R Caggiula.

78 records · Page 5Linked to original sources
PubMed1966

"Copulation-reward site" in the posterior hypothalamus.

Posterior hypothalamic selfstimulation of male rats, in which monopolar,platinum electrodes had been belaterally implanted, increased after systdmic injection of testosterone. constant stimulation to the same site elicited immediate copulation with estrous female rats. During constant stimulation males would press a bar to open a door for access to females. Even after ejaculation, males continued to open the door and to display sexual activity until stimulation terminated. Posterior hypothalamic stimulation is like normal sexual stimulation; it is rewarding, the reward varies with the amount of the sex hormone, and it elicits motivated copulation.

Animals↗
PubMedDate not supplied

The effects of low doses of morphine on the activity of dopamine-containing cells and on behavior.

Intravenous (IV) administration of 10 ug/kg of morphine sulfate increased the firing rate of Type A dopamine neurons but decreased the extracellular activity of Type B dopamine cells in the substantia nigra pars compacta and ventral tegmental area of anesthetized male rats. The morphine-produced increase in Type A cells was antagonized by 0.10 mg/kg of naloxone, whereas the suppression of B cells was blocked only by pretreatment with 5.0 mg/kg of naloxone. This same low dose of morphine (IV) also produced increased locomotor activity in awake male rats within 10 min of administration.

Animals↗
PubMedDate not supplied

The effects of calories and taste on habituation of the human salivary response.

The present study examined the effects of calories on salivary habituation. The rate of habituation to lemon taste was studied over 10 trials in 24 normal weight, nondieting, 18-35-year-old females. Between each of the trials, half the subjects ate low calorie, lemon gelatin, total Kcal = 32, and the others ate high calorie, lemon gelatin, total Kcal = 320. A dishabituating, novel chocolate taste was presented on trial 11 and recovery of salivation was assessed by presenting lemon flavor on trial 12. Subjective ratings were taken before and after salivary habituation for hunger levels and hedonics for lemon taste. Results show that high- and low-calorie groups both habituated to the repeated presentation of lemon taste, but with no significant differences as a function of calories in salivation volume, rate of habituation, hunger level decreases, and hedonic decreases. Subjects in both groups perceived equal caloric intake. These results suggest that salivary habituation may be affected more by the sensory characteristics of the food than by differences in caloric intake. The generalization of these data to the development of satiety are discussed.

Adolescent↗
PubMedDate not supplied

Sympathetic reactivity to acute stress and immune response in women.

We evaluated if the effects of acute stress on immune parameters were apparent in only the women who showed concomitant and substantial sympathetic nervous system activation and after statistical adjustment for changes in plasma volume. Nineteen women in the follicular stage of their menstrual cycles were assessed for immunological responsiveness to a series of three 3-minute psychological tasks, which reliably elicit cardiovascular and neuroendocrine stress responses. Women were classified as high or low sympathetic reactors based on their cardiovascular and neuroendocrine responses to one of the three tasks, a public speaking task. The stress-induced decreases in CD4+ percentage and increases in natural killer cell number and cytolytic activity were only apparent among the high reactors. Further analysis adjusting for alterations in plasma volume changes showed that the increase in NK cell number remained. Stress-induced proliferative responses to pokeweed mitogen and phytohemagglutinin were not more apparent among high reactors. These results are consistent with the hypothesis that the sympathetic nervous system plays a direct role in modulating the short term response to stress of some indices of the immune system in women.

Acute Disease↗