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A F Crine

Publications and source records attributed to A F Crine.

14 recordsLinked to original sources
PubMed1988

Cardiovascular structural changes induced by isolation-stress hypertension in the rat.

The cardiovascular structural remodelling associated with psychogenic hypertension was investigated in genetically normotensive rats subjected to isolation stress. Male Wistar rats were stressed by intermittent social isolation and compared to control rats living in groups. The stressed rats had higher systolic blood pressures than the control rats throughout the study. After 1 week of isolation, ornithine decarboxylase activity, a marker for hypertrophy, was increased in the right ventricle of the stressed rats. After 6 weeks of intermittent isolation, the myocardium of the stressed rats was hypertrophied, involving both right and left ventricles. The aorta was also hypertrophied, whereas the tail artery remained unaffected. Later, after 12 weeks of isolation, the left ventricular hypertrophy persisted whereas the right ventricle and aorta returned to normal. It seems, therefore, that social stress hypertension is accompanied by very early structural changes, which affect at least the heart and the aorta, and cannot be directly linked to the severity or duration of hypertension.

Animals↗
PubMed1984

Vasopressin effects on food-rewarded learning tasks might be due to its action on carbohydrate/lipid metabolism, not memory.

Vasopressin (VP) has been implicated in memory processes on the basis of effects observed in aversively motivated learning situations. Therefore researchers have tried to confirm this role by using food-motivated learning tasks. However, the well-established physiological influences of VP on carbohydrate and lipid metabolism were not taken into consideration. At various times following administration, VP might act as a feeding stimulant or as a satiating agent. Experimental designs should allow for these effects when food-rewarded learning paradigms are used to determine whether VP acts on memory.

Animals↗
PubMed1984

Dose-related influence of arginine-vasopressin on a passive avoidance behavior: effect of rearing conditions.

The present experiment was conducted in order to determine what effects administration of arginine-vasopressine (AVP) would have on post weaned male rats, reared for 44 days either in relative social isolation or in group and tested in a cross-through passive avoidance task. AVP (0.0; 0.1 and 1.0 micrograms/rat) was injected subcutaneously immediately after the application of the electric footshock (0.3 mA for 2 sec). The individual post-weaning housing significantly impaired the passive avoidance performance in rats treated with saline (0.0 micrograms) and in rats treated with 1.0 micrograms AVP. No difference, however, was observed between isolated and group-reared rats injected with 0.1 micrograms AVP. It was concluded that AVP acts upon the passive avoidance performance by changing the animal's state of arousal in a non-monotonic dose-dependent manner.

Animals↗
PubMed1983

Daily behavioral manipulation increases the total immunoreactive serum neurophysin concentrations irrespective of the duration of water deprivation in rats.

The daily training of rats in a two-compartment test box is sufficient to involve an increase in the total immunoreactive serum neurophysin concentrations when compared to totally undisturbed controls. Furthermore, this training is capable of masking the differences in neurophysin concentrations usually seen in unmanipulated rats after different durations of water deprivation. To interpret these high neurophysin levels, we speculatively suggest the existence of hypothalamic compensatory biosynthetic mechanisms which would induce the formation and/or the release of neurophysin pools under stress. Additionally, we propose that some subnuclei of the paraventricular nuclei are the neuroanatomical substratum of these mechanisms.

Analysis of Variance↗
PubMed1983

Effect of daily pretrial injection of oxytocin on rat behavior in the open-field situation.

This experiment was conducted to investigate the effects of daily pretrial intraperitoneal injection of oxytocin on behaviors of rats in an open-field situation. The group treated with 0.055 micrograms of oxytocin did not show any behavioral changes except the defecation score which was significantly more elevated than in controls. The group treated with 0.11 micrograms showed a general locomotor activity and a number of rearing behavior significantly more elevated than in all three other groups. The defecation and the grooming scores were however not different from controls. Finally, the group treated with 0.22 micrograms did not present any behavioral difference when compared with controls. Only the defecation score was significantly lower than in all the other groups. It is suggested that daily injection of oxytocin affects the arousal rather than the emotionality level.

Animals↗
PubMed1983

Changes in total serum immunoreactive neurophysins and corticosterone levels after restraint stress in rats.

This study indicates that total immunoreactive circulating neurophysins (IRN) increased in male rats submitted to acute restraint stress. Total immunoreactive serum corticosterone levels also were elevated, confirming the stressful character of the restraint situation. It is speculatively suggested that IRN elevations due to stress are the reflection of a corticotropin releasing factor (CRF)-IRN product.

Animals↗
PubMed1982

Effect of a high dose of vasopressin on an inhibition avoidance response.

1. This experiment was performed to assess the action of a posttrial high dose of lysine-vasopressin (20.0 I.U./kg) on the maintenance of an inhibitory avoidance response measured in a modified step-through test. 2. In the 24 hr, 48 hr, 72 hr, and 192 hr testings, there was a progressive increase in latencies for control and vasopressin-treated groups. However, in the 384 hr testing, the latency score shown by the experimental group dropped as compared with saline-treated group. 3. These preliminary data suggested there was a non-monotonic time-dependent dose/response curve for behavioral effects of vasopressin.

Animals↗
PubMed1981

[Modulation of the hypothalamo-neurohypophyseal system following environmental changes in rats].

The innate light-dark avoidance (step-through apparatus) was observed daily on 5 successive days in dehydrated and normal rats, the dehydration starting 24 hr before the first observation. We noted that latency scores from dehydrated groups and from the hydrated group tested together with a dehydrated group increased progressively. These significantly increased latencies did not appear when normally hydrated rats were tested alone. These changes in the temporal development of latencies seemed to be due to the fact that dehydrated rats were able to produce "fear odors" which increased the emotional reactivity of normal rats as well as theirs. The hypothalamo-neurohypophyseal function, characterized by the peripheral total neurophysins levels, also seemed to be modulated by these psychosocial and physical stresses. The neurophysins values from the hydrated group tested together with a dehydrated group were not statistically different from those of the latter group whereas they were higher than those of the hydrated group tested alone (Mann-Whithney; U = 28; n1 = n2 = 10; approach the significance). Further investigations are needed before establishing a definite relationship between the changes in latency scores on the one hand and the changes in neurophysins levels on the other hand. Nevertheless, one may well suppose that peripheral neurophysins levels play their own role in the adaptation of the organism to the environmental variations rather than only reflect the activity of the hypothalamo-neurohypophyseal axis.

Animals↗
PubMedDate not supplied

Electric footshocks differentially affect plasma and spinal cord vasopressin and oxytocin levels.

Rats exposed for three minutes to repeated electric footshocks showed an approximate 10-fold increase of basal plasma vasopressin (AVP) and oxytocin (OXT) levels. In contrast, spinal AVP and OXT contents measured in the same rats remained unchanged when compared to undisturbed controls. This observation suggests that spinal AVP and OXT do not play a major role in the short-term adaptation of the organism to stress.

Animals↗
PubMedDate not supplied

Peripheral neurophysins changes under mild stress conditions.

Total immunoreactive neurophysins levels increased significantly in rats after they had been trained in a situation based on the innate light-dark avoidance principle. These levels varied according to the amount of 'familiarisation cues' which characterised the situation. The results are discussed in terms of arousal/stress-neurophysins relationships.

Animals↗