Increase In Irritability Research Articles

Effects of olfactory bulbectomy on NMDA receptor density in the rat brain: [ 3H] MK-801 binding assay

Olfactory bulbectomy (OBX) transects the glutamatergic efferents from the olfactory bulbs, and the changes of glutamatergic N-methyl- d-aspartate (NMDA) receptor-mediated function are though to be involved in the behavioral deficits seen in OBX rats. In the present study, irritability scores in OBX male Wistar rats were correlated with discrete regional effects on NMDA receptor function measured using a [ 3H] MK-801 binding assay. Irritability scores, measured before and for 2 weeks after OBX, showed a gradual increase in irritability after OBX. A reduction of the NMDA receptor density was observed in the cerebral cortex and amygdala 16 days after OBX, but not in the striatum, olfactory tubercle, entorhinal cortex, and hippocampus. These results demonstrate that OBX causes changes in the NMDA receptor system in certain brain regions and suggest that these changes may be responsible for the behavioral deficits of OBX rats.

Maternal drug use during pregnancy: are preterm and full-term infants affected differently?

This study examined whether preterm infants are more vulnerable to the effects of prenatal drug exposure than are full-term infants. The sample of 235 low-income African American mothers and their infants included 119 cocaine-polydrug users, 19 alcohol-only users, and 97 nonusers; 148 infants were full term and 87 were preterm. Direct effects of exposure on birth weight, birth length, ponderal index, and irritability were moderated by length of gestation: Fetal growth deficits were more extreme in later-born infants, whereas increases in irritability were more extreme in earlier born infants. Effects of exposure on cardiorespiratory reactivity to a neonatal exam were not moderated by length of gestation. In general, effects of exposure occurred for both cocaine-polydrug and alcohol only users and so could not be unambiguously attributed to either of these drugs alone.

The effect of individualized special instruction on the behaviors of nursing home residents diagnosed with dementia

This pilot study was designed to investigate the effect of an educational intervention-Individualized Special Instruction (ISI)-on 30 nursing home residents diagnosed with dementia. Ratings indicated that 18 of the residents had severe dementia and 12 residents had moderate dementia. This pilot project employed a multiple treatment, an equivalent control group design which was carried out in three phases over a three-month period. Residents who did not receive IS1 intervention showed deterioration on the aberrant behavior variables with significant increase in irritability and total scores, while residents who did receive ISI intervention did not show any significant deterioration, became more vocal, showed an increased response to touch, and spent more time on task.

Effects of Social Support and Undermining on African American Workers' Perceptions of Coworker and Supervisor Relationships and Psychological Well-being

Although social undermining is a commonly experienced stressor in human services workplaces, it has received little study in contemporary models of social work stress and burnout. Furthermore, African Americans currently make up nearly 25 percent of self-identified social workers in the United States, yet most literature on personnel relationships in human services does not reference this group. Data collected from a national sample of 288 African American members of the National Association of Social Workers were used to investigate the impact of undermining among coworker and supervisor-supervisee relationships. Multiple regression analyses revealed substantial increases in irritability, depression, anxiety, and depersonalization among social workers when social undermining was included in a set of predictor variables (age, gender, and social support). The presence of social support, however, did not diminish the impact of undermining. The authors discuss several practice and training implications of these findings.

Effect of smoke-free cigarettes on 24 h cigarette withdrawal: a double-blind placebo-controlled study

In a double-blind randomised trial, 40 cigarette smokers used either nicotine-containing or placebo smoke-free cigarettes during 24 h abstinence from smoking. Subjects in the nicotine group experienced smaller increases in irritability and difficulty concentrating and fewer urges to smoke than those who received placebo. Nicotine smoke-free cigarettes were rated as more satisfying, more helpful and more effective in relieving craving than placebo. After 24 h use nicotine smoke-free cigarettes provided average blood nicotine levels of 6.3 ng/ml, i.e., 29.2% of smoking levels. The most frequent side effects were irritation of the throat and coughing. Overall, side effects were rated as not serious. Although the smoke-free cigarette in its present form is not very efficient in delivering nicotine, it was effective in alleviating initial tobacco withdrawal. It is possible that by providing both nicotine and "behavioural" replacement it may be particularly useful in the first stages of stopping smoking. The product is worth further investigation.

Clinical manifestations of cows' milk allergy in childhood. I. Associations with in-vitro cellular immune responses.

In this study 51 children who presented with symptoms of cows' milk allergy (CMA) were categorized clinically by their response to cows' milk challenge. Forty-two patients had unequivocal evidence of CMA and nine were milk tolerant. Of the patients with CMA two groups were identified. The first, made up of 32 patients, had immediate-type hypersensitivity reactions to milk associated with both positive skin-prick test (SPT) and RAST. The second group of 10 late reacting patients developed symptoms of CMA over several hours or days; significant increases in irritability, frequency of bowel actions, and rhinitis following milk ingestion were noted in this group. Leucocyte inhibition factor (LIF) produced in response to alpha-lactalbumin, beta-lactoglobulin and alpha-casein was assessed in the immediate and late reacting CMA patients as well as in the milk-tolerant group. There was no difference in LIF production between the milk-tolerant group and those with immediate reactions. However, these two groups produced less LIF than the late reacting patients for alpha-lactalbumin (P = 0.02), alpha-casein (P = 0.03) and beta-lactoglobulin (P = 0.05). A clinical dairy score card was found to be a useful instrument to assess the response of non-immediate reactions to milk ingestion.

Effects of Transdermal Clonidine Treatment on Withdrawal Symptoms Associated With Smoking Cessation

In a double-blind, randomized, placebo-controlled trial, we studied 40 cigarette smokers to determine the effects of one week of transdermal clonidine hydrochloride (Catapres-TTS No. 2) treatment on the withdrawal symptoms associated with smoking cessation. Subjects were instructed to maintain their usual cigarette intake during days 1 through 3 and cease smoking for days 4 through 6. All of the withdrawal symptoms measured (craving, irritability, anxiety, restlessness, difficulty concentrating, and hunger) significantly increased during the three days of smoking cessation in the placebo group. There was a 4.3-fold increase in craving, a 3.8-fold increase in irritability, a 3.7-fold increase in anxiety, and a 3.3-fold increase in restlessness in the placebo group compared with the transdermal clonidine group during the three days of smoking cessation. Impairment of concentration and hunger were not significantly diminished by transdermal clonidine treatment during smoking cessation. In addition, a trend was present in the transdermal clonidine group to spontaneously decrease the number of cigarettes smoked per day during the smoking period. Side effects were generally mild. We conclude that transdermal clonidine treatment ameliorates some of the short-term withdrawal symptoms, especially craving, associated with smoking cessation.

Effects of raised body temperature on reasoning, memory, and mood.

Volunteers' body core temperatures were raised to 38.80-39.05 degrees C within a few minutes by immersion in water at 41 degrees C. Tests were then made with the subjects insulated and cooling slowly. Control immersions were made in water at 37 degrees C when core temperatures remained at 36.60-37.40 degrees C. Neither memory registration nor recall of memories registered an hour earlier, nor immediate ability to recall digit spans forward or backward was affected by the increase in core temperature. The increase in temperature did not have any significant effect on accuracy of performance of verbal logic problems or of two-digit subtractions. However, the increase in core temperature was associated with a significant increase in the speed of performance of the tests, by 11 and 10%, respectively. The warm immersions also induced a significant decrease in alertness and an increase in irritability as assessed subjectively by the volunteers; control immersions had no such effects.

The vomeronasal system, aggression, activity, and passive-avoidance learning in hooded rats

Muricidal behavior, irritability to handling, open-field activity, passive-avoidance learning, and weight change were measured in Long-Evans hooded rats after they had been subjected to olfactory bulb removal, cuts of the vomeronasal nerves, lateral olfactory bulb damage, or control operations. Bulbectomized animals displayed increases in irritability to handling, enhanced horizontal activity in the open field, and a deficit in passive-avoidance learning. Animals with lateral olfactory bulb lesions showed an increase in muricidal behavior. Although there were significant intragroup postoperative weight losses, there were no significant differences between groups. Damage to the vomeronasal system alone was not involved in any of the measured behaviors.

Side Effects of Anabolic Steroids in Weight-Trained Men

In brief: This study documents the patterns of use of anabolic steroids in 32 body builders and power lifters. These subjects and seven control athletes who had never used steroids were interviewed and underwent a medical examination including 28 diagnostic blood tests and a urinalysis. Gynecomastia was detected in 4 of the 20 current users and 1 of the other 19 subjects. Sixty-seven percent of users reported temporary changes in libido, and 56% reported a temporary increase in irritability or aggressive behavior. Physicians should tell patients about the possible adverse side effects of such agents.

Reactions of guinea pig subcutaneous connective tissue to direct or long distance exposure to parachlorophenol- or formalin-containing endodontic drugs

The irritating properties of four root canal disinfecting agents were tested, either in direct contact with or at some distance from subcutaneous tissue in the backs of guinea pigs. The agents were implanted in polyethylene tubes. After ten days, the animals were killed for histologic evaluation. Significantly more irritation than with the control treatment was found using chlorophenol camphormenthol, formocresol, or 25% formalin in 80% ethanol. Twenty percent parachlorophenol in 80% ethanol caused no significant increase in irritation compared with the controls. A significant difference in irritating effect was also found between direct and long distance application of the agents. The irritating properties of four root canal disinfecting agents were tested, either in direct contact with or at some distance from subcutaneous tissue in the backs of guinea pigs. The agents were implanted in polyethylene tubes. After ten days, the animals were killed for histologic evaluation. Significantly more irritation than with the control treatment was found using chlorophenol camphormenthol, formocresol, or 25% formalin in 80% ethanol. Twenty percent parachlorophenol in 80% ethanol caused no significant increase in irritation compared with the controls. A significant difference in irritating effect was also found between direct and long distance application of the agents.

Hyperreactivity, muricide, and intraspecific aggression in the rat produced by infusion of local anesthetic into the lateral septum or surrounding areas.

Intracranial infusions of a local anesthetic (lidocaine, 2%) were made bilaterally (4 microliter over 20 min) through permanently implanted cannulas ending in the lateral septum or adjacent areas. Increases in irritability and reactivity to the experimenter, muricide, and intermale aggression were produced by injections into the lateral septum and the region ventral to it. The increases in reactivity and interanimal aggresion occurred in varying degrees and were independent of one another, but intermale aggression occurred only in animals showing muricide. The most effective site for eliciting the entire spectrum of aggressive behaviors was the region ventral to the anterior septum. The region ventral to the posterior septum (medial preoptic area, anterior hypothalamic area, straia terminalis) was unique in that it tended to produce a high incidence of muricide, with only modest increases in reactivity. The lateral septum was moderately effective in producing the entire range of aggressive behaviors. No changes in behavior were noted with infusions into the medial septum or th medial forebrain bundle/lateral preoptic area ventrolateral to the septum. It is suggested that the hyperreactivity and irritability may be relat to hyperdefensiveness and that muricide and intermale aggression are points on a continuum of interanimal aggressiveness.

Effects of sleep deprivation on mood and central amine metabolism in depressed patients.

Nineteen patients, each hospitalized with a major depressive episode, were deprived of sleep for one night. Ten patients responded with clear improvement in depressive symptoms; the substantial clinical change was transient, usually lasting one day. Those who responded had significantly higher initial depression ratings (P less than .01) and tended to be older than nonresponders who experienced mild increases in irritability, fatigue, and discomfort following sleep deprivation. Amine metabolites, 5-hydroxyindoleacetic acid (5HIAA), and homovanillic acid (HVA) were not substantially affected by sleep deprivation, although there was a significant interaction of clinical response and direction of 3-methoxy-4-hydroxyphenylglycol (MHPG) change. Sleep deprivation thus produces acute, but only transient improvement in a selected group of severely depressed patients; it appears to be an important tool in the study of the affective disorders.

Behavioral effects of norepinephrine and dibutyryl 3′,5′ AMP in centrally sympathectomized rats

Male Wistar rats were injected intraventricularly with two doses of 250 μg of 6-hydroxydopamine (6-OHDA) at a 48 hr interval. Seven days after the second injection, 50 μg of norepinephrine (NE) or 100 μg of dibutyryl cyclic AMP (DCAMP) were injected intraventricularly. There were no differences in gross behavior but an increase in irritability was observed in rats treated with 6-OHDA compared with controls. NE increased locomotor activity and irritability of animals. Chemical sympathectomy intensified locomotor excitation and irratibility caused by NE. DCAMO caused an increase of locomotor activity, irritability and convulsions 30 min after injection. These behavioral phenomena were intensified in animals treated with 6-OHDA. It is suggested that 6-OHDA sensitizes the central nervous system to action of NE and DCAMP.

Effects of olfactory bulb removal on fear responses and passive avoidance in the rat

Following complete bulbectomies, male hooded rats showed an increase in irritability and difficulty of handling, but a decrease in timidity or fear responses. After rats had learned to drink in an open field, a cat was confined in the center, and fear was defined by the behavior of controls, viz., almost total suppression of drinking and long periods of freezing, broken by brief bursts of high-speed activity. Bulb animals could not have differed more radically. Bulbs showed neither freezing nor suppression of drinking. The present results could not be attributed to differences in shock reactivity; nor could they be attributed to differences in learning or retention. Bulb animals also showed an impairment on the acquisition of step-down passive avoidance but no difference in step-downs after acquisition. These results argue against an impairment of response inhibition. The present study suggests that bulbectomy increases irritability and decreases timidity.

Daily Variation in the Sensitivity of Mimosa with Special Reference to the Action of Light

1. The irritability of Mimosa pudica rises rapidly during the first part of the morning, remains high throughout the daylight hours, and falls gradually during the night to a minimum around daybreak. 2. If plants are kept under continuous illumination for 24 hours, irritability does not fall during the night period as normally occurs but remains at the high daytime level. 3. If plants are kept in the dark for 24 hours, irritability does not rise during the daytime period as normally occurs but remains at the low nighttime level. 4. It is concluded that the increase in irritability during the day is due primarily to the effect of light. 5. Other investigators have found contrary to our observations that the irritability of Mimosa is lowest in the daytime and highest in the night. This contradiction in results is attributed to the use by other observers of an improper criterion and method for determining irritability.

The summation of stimuli

The phrase, “summation of stimuli,” has been employed at times to signify only the phenomenon in which a stimulus of a fixed intensity, which at first is too weak to stimulate living substance, will upon repetition be followed by a response. It is more rational to include within the concept all cases of summation, whether the stimulus is at first below the stimulation threshold or above it. Summation is usually ascribed to an increase in the irritability of the protoplasm, but the conditions responsible for such increase have not been known. Two years ago, the senior author explained the increase in irritability found in the treppe of muscle, by the augmenting action of fatigue substances, notably carbon dioxide and lactic acid. This chemical theory of the treppe is here applied to the explanation of summation in general. The validity of this explanation has been confirmed by a large variety of experiments performed on the muscles of medusæ and crustaceans. It has long been known that summation with subminimal stimuli is very readily obtained in these forms. The authors have confirmed this. They have also studied the action on the muscles of carbon dioxide and lactic acid in small quantities.