Dynamics of the activity of the postural asymmetry factor after unilateral damage to the motor area of the cortex

The authors studied the time-course of functional rearrangements of the segmental apparatus after unilateral injury of the rat motor cortex. It was found that one day after injury the postural asymmetry of the hind limbs was fixed by the lumbal region of the spinal cord. This functional state of the segmental apparatus lasted 10 days after injury in the presence of the maximal activity of postural asymmetry factor (PAF) in the CSF and increasing activity of the factor in the brain tissue. Recovery of the segmental apparatus to symmetrical function by the end of the third week following injury was accompanied by PAF inactivation.     

The modulation of postural asymmetry in recipient animals under the influence of the cerebrospinal fluid from patients with manic-depressive psychosis

Suboccipital administration of cerebrospinal fluid of patients with affective disorders elicits a pose asymmetry in rats-recipients; the character of the pose asymmetry depends on the phase of donor's disease: cerebrospinal fluid of manic patients elicits a relative flexion of the right posterior limb, of depressive patients--a relative flexion of the left posterior limb. High-molecular and low-molecular fractions of the cerebrospinal fluid were active, trypsin treatment led to disappearance of the effect. The results suggest a significant role of protein components of the cerebrospinal fluid in the organization of the symptom of functional asymmetry of the central nervous system under affective disorders.     

Characteristics of the development of postural asymmetry in rats as affected by the opioids met-enkephalin and the kappa-agonist bremazocine

It has been found that bremazocine and met-enkephalin induce postural asymmetry in spinal rats under subarachnoidal and intravenous administration. Intravenous administration of bremazocine to intact animals--even if after it (an hour later) their spinal cord is sectioned--produces no asymmetry, i. e. the spinal cord section is necessary for asymmetry development. The magnitude of postural asymmetry and the side of limb flexion are not constant for each animal, but they change in time. Though, on the average, the percent of asymmetric animals and the ratio of left and right flexions in each group of animals are practically constant. When the spinal cord is sectioned at the T1-T4 level, the bremazocine and metenkephalin induce mainly the right-leg flexion: when the section is made at the T5-T9 level, the left-leg is bent, i. e. the flexion side depends on the level of the section. It is suggested that the ability of opioids to induce postural asymmetry is based on lateralization of opioid receptors in the rat spinal cord.     

Anticonvulsive effect of the cerebrospinal fluid of cats with epileptic status

We studied the properties of the cerebrospinal fluid obtained from the cats with a formed epileptic status. Samples of such fluid were injected into the rats, in which later on such epileptic status was modeled. The clearly expressed anticonvulsive efficacy of such cerebrospinal fluid is demonstrated; it was manifested in a decrease of the duration of seizure reactions and prevention of the development of generalized clonico-tonic attacks. It is concluded that this effect is not species-specific, and the possible nature of an anticonvulsive profile of the fluid is discussed.     

Inactivation of the postural asymmetry factor at the stage of compensation for the postural disorder induced by unilateral removal of the motor area

The peptide nature of the posture asymmetry factor (PAF) produced in the brain after unilateral removal of the motor region of the neocortex was established. The inactivation of PAF activity in the brain toward the end of the third week after the removal is due to PAF inactivation by the endogenous factor absent from the intact brain. The molecular weight of the inactivation factor exceeds 5.0 kD that makes it possible to separate it from the PAF by gel filtration on Sephadex G-25. The correlation was marked between the increasing activity of the PAF inactivation factor and the recovery of the initial symmetric functioning of the spinal centers during three weeks after unilateral damage to the CNS.     

The nature of factors inactivating postural asymmetry factor at the initial stages of compensatory reconstruction in animals with unilateral lesions of the motor neocortex

The disappearance of posture asymmetry factor activity in the CSF after three weeks of unilateral removals of the neocortex motor region is caused by inactivation factors (IF), which are thermolabile proteins with m.v. about 80 kD and 150 kD. One of IF (150 kD) interacted with protein A which shows its immunoglobulin++ nature.     

The excitability of dorsal horn neurons is affected by cerebrospinal fluid from humans with osteoarthritis

Changes in central neural processing are thought to contribute to the development of chronic osteoarthritis pain. This may be reflected as the presence of inflammatory mediators in the cerebral spinal fluid (CSF). We therefore exposed organotypically cultured slices of rat spinal cord to CSF from human subjects with osteoarthritis (OACSF) at a ratio of 1 part CSF in 9 parts culture medium for 5-6 days, and measured changes in neuronal electrophysiological properties by means of whole-cell recording. Although OACSF had no effect on the membrane properties and excitability of neurons in the substantia gelatinosa, synaptic transmission was clearly altered. The frequency of spontaneous excitatory postsynaptic currents (sEPSC) in delay-firing putative excitatory neurons was increased, as was sEPSC amplitude and frequency in tonic-firing inhibitory neurons. These changes could affect sensory processing in the dorsal horn, and may affect the transfer of nociceptive information. Although OACSF also affected inhibitory synaptic transmission (frequency of spontaneous inhibitory synaptic currents; sIPSC), this may have little bearing on sensory processing by substantia gelatinosa neurons, as sEPSC frequency is >3× greater than sIPSC frequency in this predominantly excitatory network. These results support the clinical notion that changes in nociceptive processing at the spinal level contribute to the generation of chronic osteoarthritis pain.     

Dynamics of the activities of postural asymmetry factors and of the recovery of motor function in damage to the neocortex of the left and right hemispheres

The role of postural asymmetry factors in the recovery of motor function after unilateral cortical lesions was investigated. The differences in the time-course of motor reactions recovery after left- and right-sided cortical damage was found. A more effective compensation of motor defects in animals with left-sided damage was accompanied by stable activity of postural asymmetry factors. The reported results indicate an important role of postural asymmetry factors in the early compensatory intra-central rearrangements.     

The activity of postural asymmetry factors in symmetrical sections of the rat spinal cord

The distribution of the low-molecular weight and high-molecular weight postural asymmetry factors (FPA) activity in the left and right parts of the lumbal region of the rat spinal cord was studied. Low-molecular weight FPA induces flexion of the hind limb ipsilateral to the half of the spinal cord from which FPA was isolated, while high-molecular weight FPA induces contralateral flexion. The activities of the low- and high-molecular weight FPAs in each half of the spinal cord are comparable in normal rat. After the suction lesion of the motor areas in the left hemisphere the increase of the low-molecular weight FPA activity in the right half of the lumbal region of the spinal cord was observed.     

The phenomenon of the replication of ontogenetic immaturity in adult cats caused by the cerebrospinal fluid of kittens

Studies have been made on the electrical activity of muscles in the hindlimbs in kittens and adult cats before and after injection the liquor from 10-, 21-day and 1-month kittens into the lumbar part of the spinal cord. Analysis was made of the EMG at rest and that of the evoked reactions. It was shown that EMG of adult cats after injection of kitten liquor attained the pattern typical of the donor. The data obtained indicate the presence in kitten liquor of biologically active substances which account for the level of regulatory relationships. Transfer of these substances to adult animals results in the formation of a new level of coordinations of movements which corresponds to immature organism.     

Demonstration of T lymphocytes in human blood and cerebrospinal fluid with Helix pomatia A hemagglutinin

Peroxidase-labelled Helix pomatia A hemagglutinin (HPH) was used as a T-cell marker for neuraminidase-treated human lymphocytes from blood or cerebrospinal fluid (CSF). Lymphocytes from the blood of 22 patients with noninflammatory diseases of the central nervous system and from the CSF of 16 patients with noninfectious diseases and 29 patients suffering from meningitis or meningoencephalitis were studied. Most HPH-binding cells were found in normal CSF. The variance in the number of reactive lymphocytes was higher in the CSF from patients with inflammatory diseases than in the other types of samples.     

Demonstration of the biosynthesis of prostaglandins from arachidonic acid by rat adrenal cortex cells in culture

The biosynthesis of prostaglandins of the E pathway was shown in new-born rat adrenocortical cells in long-term primary culture, by direct incubation of labelled arachidonic acid or by incubation with prelabelled cells. A rapid method of extraction was developed using silanised silica cartridges.