R. S. Arutyunyan

Learn More
Dynamic studies were performed in conditions of hypoxia on the effects of stimulation of the ventral, lateral, and medial nuclei of the septum on the spike activity of bulbar respiratory neurons and respiration. The various phases of hypoxia provided a model experiment over which the overall effects of the septal neurons were summed. Electrical stimulation(More)
The last contractile responses (LCRN), where N is the number of individual contractile responses within tetanus, were separated from the integral tetanic responses of fast, m. Extensor digitorum longus (m. EDL), and slow, m. Soleus, rat muscles using a computer-graphic technique. The average amplitude of LCR5 in m. Soleus at a 20 Hz stimulation rate(More)
Using a computer graphics approach, the last contractile responses (LCRN, where N is a number of elementary contractile responses in tetanus) were separated from integral tetanic responses of rat fast muscles, m. Eхtensor digitorum longus (m. EDL), and slow muscles, m. Soleus, evoked by trains of 5, 10 and 50 stimuli. In m. Soleus, at a stimulation(More)
Comparison of amplitude-time characteristics of fast extensor digitorum longus muscles (m. EDL) isolated from control rats and rats with model of acute streptozotocin-induced diabetes mellitus (DM) 12 and 30 days after treatment with streptozotozin did not reveal significant changes of strength of single normalized contractile responses as compared with(More)
The study reported here seeks to explain the roles of different limbic system formations in controlling respiration in conditions of oxygen insufficiency. The effects of stimulation of the olfactory bulbs (OB) on medulla oblongata respiratory center (RC) neurons during exposure to hypoxia were studied in a laboratory barochamber. Stimulation of the OB in(More)
The effects of tenotomy present for two weeks on the post-tetanic responses of isolated fast (extensor digitorum longus) and slow (soleus) muscles were studied by isometric recording of muscle contraction in rats. After tetanic stimulation with bursts of 100 impulses at a frequency of 20 impulses/sec, the force of single fast muscle contractions exceeded(More)
93 It is known that the vertebrate skeletal muscles are highly conductive for chloride ions, the conductance (G Cl) accounting for up to 80–85% of the total conn ductance of the membrane in the resting state. The residual 15–20% of the conductance is mainly due to the potassium ion membrane conductance. The high G Cl is essential for the formation and(More)
The influences of hippocampal fields CA1 and CA3 on the spike activity of respiratory neurons in the bulbar respiratory center were studied in normal conditions and hypoxia. In normoxia, stimulation of hippocampal fields CA1 and CA3 had mainly inhibitory influences. During oxygen insufficiency, the activity responses of respiratory neurons in the bulbar(More)
Hind-limb muscles of new-born rats were de-efferented by removing the lumbosacral spinal cord. Spinal ganglia remained intact, together with their peripheral axon. The presence of sensory terminals in limb spindles, induces the full ultrastructural differentiation of muscle spindles, as has been shown previously. In the present paper we have shown by(More)
  • 1