Distribution in Rats Internal Organs of Intraperitoneally Given 125I-Labeled Heptapeptide [2-8]-Leucopyrokinin ([2-8]-LPK), a Truncated Analog of Insect Neuropeptide Leucopyrokinin.

Background: It was previously found that synthetic, insect-derived octapeptide leucopyrokinin (LPK) applied directly into the lateral brain ventricle induced a significant antinociceptive effect in rats. Its synthetic truncated analog heptapeptide [2-8]-leucopyrokinin displayed a stronger antinociceptive effect in comparison to native LPK. Moreover it was previously found a high accumulation of these both 125I-labeled peptides in adrenals, as well as in hypothalamus and in hippocampus of rats brain.

Effect of alloferon 1 on central nervous system in rats.

Alloferon 1 is an insect-derived peptide with potent antimicrobial and antitumor activity. It was isolated from blood of an experimentally infected insect, the blow fly Callifora vicina. Synthetic alloferon 1 reveals a capacity to stimulate activity of NK cells and synthesis IFN in animal and human models.

[The influence of stimulation dopaminergic D, i D2 receptors in lateral geniculate body on flash visual evoked potentials (FVEP) in rats].

Purpose: The topic of this paper is to define the influence of stimulation dopaminergic D1 i D2 receptors in lateral geniculate body by flash visual evoked potentials (FVEP).

Material And Methods: Wistar rats were examined. There were stereotaxically implanted with guide caniula into the lateral geniculate body to inject substances and with VEPs electrodes on the skull and on the surface of visual cortex.

[The influence of dopamine injected into the lateral geniculate body on flash visual evoked response in rats].

Purpose: Numerous neurotransmitters and neuromodulators operating on all levels of the visual system, influence the parameters of cortical evoked response. The aim of this study was to find the influence of dopamine (DA) injected into the lateral geniculate body (nucleus) on flash visual evoked response (FVEP).

Material And Methods: The experiments were performed on adult Wistar rats.

[Visual evoked potentials (FVEP) after the prenatal exposure to heavy metals--experimentals studies].

Purpose: To find out, if any and how deep alterations in visual tract are due to prenatal intoxication by heavy metals such as: cadmium (Cd), lead (Pb), mercury (Hg) and manganese (Mn). The measure of these alterations were the changes in flash visual evoked potentials after prenatal intoxication.

Material And Methods: The experiments were carried out on 55 white newborns Wistar rats, which were divided into 5 groups: control group (14 rats), Cd group (12), Pb (6), Hg (14) and Mn (9).

Distribution of 125I-labeled [2-8]-leucopyrokinin, active analog of leucopyrokinin in rats.

The brain and internal organs distribution of 125I-labeled [2-8]-leucopyrokinin ([2-8]-LPK), a truncated analog of leucopyrokinin (LPK), an insect myotropic peptide injected into the lateral brain ventricle was determined in rats. A high accumulation of this analog in adrenals and in the hypothalamus and hippocampus of the brain was found. A lesser but significant [2-8]-LPK accumulation in other internal organs and parts of the brain was also observed.

Leucopyrokinin (LPK) analog [d-Ala(5)]-[2-8]-LPK inhibits LPK-induced analgesia in rats.

It has been previously found in our laboratory that insect neuropeptide leucopyrokinin and [2-8]-leucopyrokinin, a truncated analog without the first aminoacid of leucopyrokinin peptide chain exert an antinociceptive effect in rats. The present study confirmed our previous results, and moreover it has been found that [d-Ala(5)]-[2-8]-leucopyrokinin, an analog of leucopyrokinin antagonized the antinociceptive effect of leucopyrokinin and of [2-8]-leucopyrokinin. We conclude that this synthetic analog is a probable leucopyrokinin antagonist.

Effect of L-arginine on memory in rats.

Effect of intracerebroventricularly (icv) or subcutaneously (sc) injected L-arginine (L-Arg) on memory was determined using the procedure of passive avoidance test. Moreover, locomotor and exploratory activity was determined in rats in an open field test. We found that either the peripheral (sc) or icv administration of L-Arg significantly prolonged latency time in the passive avoidance test.