Grooming Episodes Research Articles

Acute intracerebroventricular injections of the mast cell degranulator compound [formula omitted] and behavior in rats

The intracerebroventricular (ICV) injection of the mast cell degranulator Compound 48 80 (2.5–20.0 μg/kg) produced a marked behavioral syndrome in normotensive rats. The behaviors included head and body shakes, paw tremor, excessive grooming, unusual posture and gait, mild diarrhoea, piloerection, extreme agitation and irritability to touch, and a later phase of sedation. The highest doses (15 and 20 μg/kg) also produced catalepsy and episodes of “barrel rolling” (continous rolling of 1–8 turns around the longitudinal axis). These behaviors were observed for approximately 15–30 min although the sedation and catalepsy were maintained for 90–120 min. A second ICV injection of the 10 μg/kg dose of Compound 48 80 given 2 hr after an initial injection of this dose, produced a much reduced response and the numbers of head and body shakes, and episodes of paw tremor and grooming were between 20–30% of those produced by the first injection. The reduced effect of the second injection indicates that the behavioral effects of Compound 48 80 may arise from the acute degranulation of mast cells rather than direct effects on neuronal populations or the cerebral vasculature.

Relation of autogrooming to sexual behavior in male rats

Grooming and penile reflexes were studied in male rats that were restrained in supine position with the penile sheath retracted or were free to copulate with sexually receptive females. In Experiment 1 there was a reliable concordance in supine males between the tendency to groom and the tendency to display penile reflexes. In Experiment 2 we analyzed the sequential organization of grooming and genital events in supine tests. It was assumed that many or most episodes of ventral grooming would have been genital grooming had access to the genitalia not been prevented by restraint. Paw grooming tended to precede clusters of penile responses, whereas ventral grooming started after the onset of erections. Experiment 3 was an exploration of grooming in the context of copulation, rather than supine restraint. Males groomed their genitalia immediately after all intromissions and after all mounts that ended mount bouts. The duration of grooming was not affected by whether or not intromission occured. Finally, in Experiment 4 we observed genital and nongenital grooming and recorded electromyographic (EMG) activity from the striated bulbospongiosus muscle (mBS) of the penis in freely moving rats. Consistently, mBS activity led to genital grooming with a short latency, whereas nongenital grooming rarely led to genital grooming, and EMG activity was not associated with nongenital grooming nor did it tend to follow after genital grooming was initiated. The four experiments led, respectively, to the following conclusions: (1) A reduction in stress during adaptation to supine restraint permits or promotes grooming and either independently facilitates penile erections and flips or, possibly, the grooming itself further relaxes the male, permitting the expression of sexual reflexes; (2) It is primarily paw grooming that is caused by, and perhaps enhances, the developing adaptation to restraint, whereas genital grooming is precipitated in particular by the occurrence of penile reflex clusters; (3) The cutaneous stimulation received by the penis during copulation may not be a significant factor in regulating the probability or duration of genital grooming; (4) Changes in the penis or in neural activity associated with penile erections are more likely to lead to genital grooming than vice versa. It follows that pharmacological and other physiological treatments may affect the incidence of genital reflexes and grooming by influencing part of a chain of events of by affecting a process (e.g., “stress” or adaptation to stress) that in turn can affect the incidence of both sexual reflexes and grooming.

CRF-induced excessive grooming behavior in rats and mice

We studied the grooming response to lateral ventricle injection of CRF in both rats and mice under similar conditions. One microgram of CRF ICV induced a pronounced increase (3- to 4-fold) in the frequency of self-grooming in rats, but only a much smaller (less than 20%) increase in mice. The minimum effective dose of CRF in rats was 300 ng. Although ACTH 1–24 induced less grooming in mice than in rats, the difference in potency did not appear to be sufficient to explain the differences between the effectiveness of CRF in the two species. Whereas ACTH increased all types of grooming scored, CRF increased all forms of grooming except flank scratching with the hind limb. The major effect of CRF was to increase the number of episodes of grooming, whereas ACTH 1–24 tended to prolong the length of individual episodes. The excessive grooming induced by ICV CRF was not affected by prior treatment with dexamethasone, suggesting that the increased grooming was not due to secondary release of ACTH from the pituitary. Nevertheless, ICV CRF might induce grooming by releasing MSH/ACTH from cerebral storage sites. CRF-induced grooming, like ACTH-induced grooming, was inhibited by naloxone pretreatment. Despite the small qualitative differences, CRF-induced grooming could be due to secondary release of ACTH.

Behavioural and ECoG spectrum power effects after intraventricular injection of drugs altering dopaminergic transmission in rats

In rats with cannulae permanently implanted into the third cerebral ventricle, the effects of different pharmacological manipulations affecting dopaminergic mechanisms, were studied on behaviour and electrocorticographic (ECoG) activity, continuously quantified in its spectrum power. The intraventricular injection (0.1–1 nmol) of ( − )3PPP[3-(3-hydroxyphenyl) N- n-propylpiperidine], a specific agonist at dopamine (DA) autoreceptors, produced dose-dependent behavioural sedation or sleep and an increase in ECoG spectrum power, with a predominant increase in the lower frequency bands. Short episodes of stereotyped movements, wet-dog syndrome, penile grooming and erection were also observed. Similar behavioural and ECoG effects were elicited by the intraventricular injection of R-( + )-8-chloro-2, 3,4,5-tetrohydro-3-methyl-5-phenyl-1H-3-benzazepine-7-ol (SCH 23390), a selective antagonist at D 1 postsynaptic receptors, although these were preceded by a short period of behavioural and sexual stimulation. In addition, the intraventricular administration of some neuroleptics, chloropromazine and haloperidol, produced behavioural and ECoG slow wave sleep. No significant changes were observed with a neuroleptic drug, 1-sulpiride, which is reputed to act selectively as an antagonist at dopamine D 2 receptors. In conclusion, the present experiments add new evidence in favour of the idea that dopaminergic mechanisms are involved in mammalian species in the control of arousal and that both post-synaptic D 1 and D 2 receptors may take part in such a control.

Radio-Transmitter Implants in 4 Species of Small Mammals

A simple surgical procedure was used to implant radio transmitters intraperitoneally in deer mice (Peromyscus maniculatus), montane voles (Microtus montanus), Ord's kangaroo rats (Dipodomys ordii), and Townsend's ground squirrels (Spermophilus townsendii) in southeastern Idaho. Transmitters were implanted in 105 individuals from 1982 through 1985; 85 (81%) survived and were known to be alive in our study area 1 month after surgery. Survival rates for 60 deer mice, 22 montane voles, 16 Ord's kangaroo rats, and 7 Townsend's ground squirrels were at least 85, 77, 69, and 86%, respectively. Although the transmitter package weight:small-mammal body weight ratios often exceeded those recommended, neither locomotor abilities nor behavior were perceptively affected. The technique appeared to offer a viable method of fitting these semifossorial species with radio transmitters. J. WILDL. MANAGE. 51(1):105-108 The development of modern radio-telemetry equipment and techniques has redefined the scope and power of studies requiring marked animals. Individual animals can be located, identified, and monitored relatively easily. This allows a predictable data acquisition strategy that relies less on chance encounters or other vagaries of classical marked-animal studies. For example, fitting small mammals with radio transmitters avoids the biases of trap aversion or trap happiness inherent in multiple recapture studies. For most radio-tagged mammals the transmitter is externally attached by some sort of collar device. However, for some small-mammal species conventional collars are inappropriate. For example, white-footed mice (P. leucopus), meadow voles (M. pennsylvanicus), Ord's kangaroo rats, and Franklin's ground squirrels (S. franklinii) fitted with radio collars have each experienced >1 of the following: transmitter loss, neck irritation and/or hair loss, restricted movement through burrows and/or dense vegetation, increased ectoparasite load beneath the collar, and changes in behavior (Hamley and Falls 1975, Madison 1977, Smith and Whitney 1977, Filipovich 1983, Eagle et al. 1984). Moreover, external transmitter collars damaged by extreme weather conditions, mechanical wear (Eagle et al. 1984), and/or mutual grooming episodes (Madison 1977) have prematurely failed. These problems can be overcome by surgically implanting the transmitter. Rawson and Hartline (1964) were the 1st to implant transmitters in small mammals, subcutaneously in deer mice. They concluded that, even though the implanted transmitter grossly deformed the dorsal contour of the mice, the animals' movements were not detectably hindered. Subsequent to that pioneer effort, Neely and Campbell (1973) compared the survival and response of white-footed mice to subcutaneous and intraperitoneal transmitter implants. Their results suggested that the latter implantation site was better. Using placebo transmitter packages in white-footed mice, Smith and Whitney (1977) concluded that intraperitoneal implants were both feasible and biologically optimal. Smith (1980a) examined the effect of implants on growth rates, reproduction, and survival of adult white-footed mice and found no differences between experimental and control animals. Smith (1980b) also determined that suckling whitefooted mice could successfully carry intraperitoneal implants without detriment if the implantation occurred after the venter pelage was well developed and pups' eyes had been open for >2 days. Besides white-footed mice, the success rates and/or the techniques of implanting intraperitoneal transmitters in small mammals have been reported only for Franklin's ground squirrels (Eagle et al. 1984) and meadow voles (Madison 1980). The objective of this study was to determine the successfulness of intraperitoneal trans-

Stimulation of dopamine D-1 receptors by SKF 38393 induces EEG desynchronization and behavioral arousal

The dopamine D-1 receptor agonist SKF 38393 dose-dependently (2.5–10 mg/kg) induced desychronization of the electroencephalographic (EEG) activity and behavioral arousal in both rabbits and rats. Unlike apomorphine, SKF 38393 elicited no signs of stereotyped behavior in rabbits and minimal effects, such as episodes of grooming, in rats. The effects of SKF 38393 10 mg/kg on the EEG were prevented by the selective D-1 receptor antagonist SCH 23390 at a dose as low as 0.003 mg/kg, but not by the D-2 antagonist (-)-sulpiride (25–50 mg/kg). These data provide evidence of a role of D-1 receptors in the generation of EEG activity related to behavioral arousal. In addition, this model is a valuable tool to functionally evaluate the D-1 antagonistic properties of neuroleptics.

Continuous amphetamine intoxication: an animal model of the acute psychotic episode

When amphetamines are administered to humans every few hours for several days, either during the 'speed runs' of addicts or in controlled laboratory settings, the psychosis which reliably results is similar to paranoid schizophrenia in a number of important aspects. This unique regimen of drug intake, which involves the continuous presence of stimulants over a prolonged period of time, can be simulated in animals using subcutaneously implanted slow-release silicone pellets containing d-amphetamine base. Monkeys and rats implanted with these pellets develop stages of behavioural alterations which are somewhat similar in sequence to those observed in humans who have received frequent doses of amphetamine. An initial period of hyperactivity and exploratory behaviour is followed by the gradual development of motor stereotypies which become virtually incessant. A period of relative inactivity then appears which is followed, at 4-5 days after pellet implantation, by a late stage. This final stage is characterized by 'wet-dog' shakes, parasitotic-like grooming episodes, and a variety of other forms of hallucinatory-like behaviour. At about the same time there are distinctive and partially irreversible alterations in dopaminergic innervations of the caudate nucleus, but not in mesolimbic dopamine innervation of the nucleus accumbens or in several other neurotransmitter systems. Continuous amphetamine administration may reproduce some aspects of the prolonged excitation which accompanies an acute psychotic episode and may be a fruitful model for the clarification of the dopamine theory of schizophrenia.

Cycloheximide prevents apomorphine-induced yawning, penile erection and genital grooming in rats

Apomorphine (50 μg/kg) induced repeated episodes of yawning, penile erection and genital grooming in rats. A dose of cycloheximide, which inhibited brain protein synthesis by 50% totally prevented apomorphine-induced yawning and reduced by approximately 50% the occurrence of episodes of penile erection and genital grooming. However, this treatment failed to modify the stereotyped behaviour induced by 200 μg/kg of apomorphine. These results suggest that protein synthesis is required for the behavioural effects of small doses of apomorphine.

A study of the shaking and grooming induced by RX 336-M in rats

Several endogenous peptides and experimental agents induce “wet-dog” shakes and excessive grooming after acute administration to rats, but quantitative information on a possible relationship between the two behaviors is lacking. RX 336-M (7,8-dihydro-5′,6′-dimethylcyclohex-5′-eno-1′,2′,8′,14 codeinone) is a novel compound which elicits dose-related shaking and grooming in the rat. We have measured and compared the shaking and grooming induced by several doses of RX 336-M (1.5–12 mg/kg, IP) in male Sprague Dawley rats at various stages of maturatin. Analysis of the correlation between the number of “wet-dog” shakes and the frequency of grooming episodes indicates that a relationship may exist between the shaking and grooming. The excessive grooming induced by RX 336-M may be a mechanism by which the rat's state of arousal (raised by the shaking) is lowered and homeostasis is maintained.

ACTH-induced excessive grooming in the rat

ACTH-induced excessive grooming in the rat

The effects of social restriction on the behavior of rhesus monkeys: I. Free social behavior.

Social interactions of monkeys raised in a socially-restricted laboratory environment were compared with those of feral monkeys. Pairs of restricted Ss showed more frequent and prolonged fighting and less frequent and prolonged grooming episodes than feral pairs. Differences between groups were also found in amount and integration of sexual behavior; differences between restricted and feral males were still found when they were tested with the same socially-experienced females. It is concluded that restricted social experience retards establishment of adequate responses to social cues. From Psyc Abstracts 36:02:2EO82M. (PsycINFO Database Record (c) 2006 APA, all rights reserved)