PubMed Health⌕ Search

Biomedical subjects

K P Ossenkopp

Publications and source records attributed to K P Ossenkopp.

108 records · Page 6Linked to original sources
PubMed1979

Relationship of some open-field behaviors to amygdaloid kindled convulsions in Wistar rats.

Repeated low-intensity electrical stimulation (kindling) of the amygdala eventually produces convulsive behavior in animals. The present study examined the relationship between behaviors displayed in a novel open-field situation with behavioral characteristics of the kindled clonic convulsion (CC). Wistar rats were given two open-field tests and were subsequently kindled to clonic convulsions. A multiple regression analysis indicated that rats which urinated more often in the open-field tests tended to show longer latencies to CC onset. Thus, open-field urination was a significant predictor of latency to CC onset. It is suggested that an emotionality construct may be related to rate of kindling.

Amygdala↗
PubMed1977

Dose-response effects of taurine on some open-field behaviors in the rat.

In two experiments albino rats were injected i.p. with various doses of taurine and their subsequent behavior in an open-field apparatus was observed. Increasing doses of taurine significantly decreased ambulation levels, increased latency scores, and increased thigmotaxis ('wall-hugging' behavior). In general, 50 mg/kg or more of taurine was required to produce significant changes in the dependent behavioral measures. The open-field behaviors of rearing and defecation were not significantly affected by the drug manipulation. The results of these experiments suggest that taurine may act as modulating or stabilizing agent in the central nervous-motor system rather than as a diffuse inhibitory agent.

Animals↗
PubMedDate not supplied

Magnetic fields differentially inhibit mu, delta, kappa and sigma opiate-induced analgesia in mice.

An exposure for 60 min to a 0.5 Hz rotating magnetic field (1.5-90 G) significantly attenuated the daytime analgesic effects of the mu and kappa opiate agonists, morphine and U50,488H, respectively, and significantly inhibited the analgesic actions of the delta agonist, D-Ala2-D-Leu5-enkephalin, in mice. The magnetic stimuli had no significant effects on the analgesic effects of the prototypic sigma opiate agonist (+/-) SKF-10,047. These results show that exposure to relatively weak magnetic stimuli has significant and differential inhibitory influences on various opioid systems.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMedDate not supplied

Differential inhibitory effects of MIF-1, Tyr-MIF-1, naloxone and beta-funaltrexamine on body rotation-induced analgesia in the meadow vole, Microtus pennsylvanicus.

The effects of body rotation in a horizontal plane and various opiate antagonists on the nociceptive responses of a day-active microtine rodent, the meadow vole, Microtus pennsylvanicus, were examined. Intermittent rotation (70 rpm, schedule of 30 sec on, 30 sec off) for 30 min induced significant analgesic responses in the voles for 15 min after rotation. These increases in thermal response latency were blocked by intraperitoneal pretreatment with either naloxone or the irreversible mu opiate receptor antagonist beta-funaltrexamine (beta-FNA; 10 mg/kg; 24 hr pretreatment). This antagonistic effect of beta-FNA indicates mu opioid involvement in the mediation of rotation-induced analgesia. The antiopiate peptides MIF-1 (Pro-Leu-Gly-NH2) and Tyr-MIF-1 also significantly reduced, though did not completely block, body rotation-induced opiate analgesia. This suggests that Tyr-MIF-1 and MIF-1 have significant antagonistic effects on mu opioid systems that are involved in the mediation of stress (rotation)-induced analgesia.

Analgesia↗
PubMedDate not supplied

Prenatal ethanol exposure alters rat brain morphology but does not affect amygdaloid kindling.

Exposure of the mammalian fetus to ethanol causes a variety of nervous system abnormalities, but the evidence relating to seizure susceptibility is contradictory. Therefore, offspring of rat dams that had consumed a mean of 6.9 g/kg/day of ethanol were compared with pair-fed and free-fed controls on rate of electrical kindling of the amygdala and on open field measures of activity. The Ethanol-exposed males displayed increased ambulation and the Ethanol females displayed increased rearing and defecation in an open field. However, there was no significant difference between the groups in rate of kindling. Although the gross size of the brains measured on a coronal section through the anterior tip of the hippocampus did not differ significantly among the groups, there was a highly significant reduction in percent brain tissue area and a corresponding increase in percent ventricle area in the Ethanol group.

Amygdala↗
PubMedDate not supplied

The measurement and integration of behavioral variables: aggregation and complexity as important issues.

The measurement of motor activity in animals is central to the description of animal behavior in general. A wide variety of measurement procedures have been used in the past and various researchers have suggested that multiple measures or "behavioral profiles" be used to describe the effects of various types of experimental manipulations. However, many of the measures used have been found to be unreliable. The principle of aggregation, which states that the sum of a set of multiple measurements is a more stable and representative estimator than any single measurement, allows for construction of variables which are more reliable and have greater generalizability. Examples are provided which show that the application of aggregation can substantially increase correlations within variables over time as well as between variables. Application of factor analytic procedures to multivariate motor activity data is suggested to be a useful method of reducing many variables into fewer, more complex variables, which have greater phenomenon realism. Examples of the application of such factor analytic approaches are provided, both for the traditional two-way factor analytic methods as well as a more recent procedure (PARAFAC model) developed for analysis of three-way longitudinal data sets. It is suggested that multivariate analytic procedures are appropriate for data reduction and description in the area of behavioral neuroscience.

Animals↗